diff --git a/en_US.ISO8859-1/articles/multi-os/article.sgml b/en_US.ISO8859-1/articles/multi-os/article.sgml index fb8eb035f7..1b500de65e 100644 --- a/en_US.ISO8859-1/articles/multi-os/article.sgml +++ b/en_US.ISO8859-1/articles/multi-os/article.sgml @@ -1,741 +1,741 @@
Installing and Using FreeBSD With Other Operating Systems Jay Richmond
jayrich@sysc.com
6 August 1996 This document discusses how to make FreeBSD coexist nicely with other popular operating systems such as Linux, MS-DOS, OS/2, and Windows 95. Special thanks to: Annelise Anderson andrsn@stanford.edu, Randall Hopper rhh@ct.picker.com, and Jordan K. Hubbard jkh@time.cdrom.com Overview Most people can not fit these operating systems together comfortably without having a larger hard disk, so special information on large EIDE drives is included. Because there are so many combinations of possible operating systems and hard disk configurations, the section may be of the most use to you. It contains descriptions of specific working computer setups that use multiple operating systems. This document assumes that you have already made room on your hard disk for an additional operating system. Any time you repartition your hard drive, you run the risk of destroying the data on the original partitions. However, if your hard drive is completely occupied by DOS, you might find the FIPS utility (included on the FreeBSD CDROM in the \TOOLS directory or via ftp) useful. It lets you repartition your hard disk without destroying the data already on it. There is also a commercial program available called Partition Magic, which lets you size and delete partitions without consequence. Overview of Boot Managers These are just brief descriptions of some of the different boot managers you may encounter. Depending on your computer setup, you may find it useful to use more than one of them on the same system. Boot Easy This is the default boot manager used with FreeBSD. It has the ability to boot most anything, including BSD, OS/2 (HPFS), Windows 95 (FAT and FAT32), and Linux. Partitions are selected with the function keys. OS/2 Boot Manager This will boot FAT, HPFS, FFS (FreeBSD), and EXT2 (Linux). It will also boot FAT32 partitions. Partitions are selected using arrow keys. The OS/2 Boot Manager is the only one to use its own separate partition, unlike the others which use the master boot record (MBR). Therefore, it must be installed below the 1024th cylinder to avoid booting problems. It can boot Linux using LILO when it is part of the boot sector, not the MBR. Go to Linux HOWTOs on the World Wide Web for more information on booting Linux with OS/2's boot manager. OS-BS This is an alternative to Boot Easy. It gives you more control over the booting process, with the ability to set the default partition to boot and the booting timeout. The beta version of this programs allows you to boot by selecting the OS with your arrow keys. It is included on the FreeBSD CD in the \TOOLS directory, and via ftp. LILO, or LInux LOader This is a limited boot manager. It will boot FreeBSD, though some customization work is required in the LILO configuration file. About FAT32 FAT32 is the replacement to the FAT filesystem included in Microsoft's OEM SR2 Beta release, which started replacing FAT on computers pre-loaded with Windows 95 towards the - end of 1996. It converts the normal FAT file system and + end of 1996. It converts the normal FAT filesystem and allows you to use smaller cluster sizes for larger hard drives. FAT32 also modifies the traditional FAT boot sector and allocation table, making it incompatible with some boot managers. A Typical Installation Let's say I have two large EIDE hard drives, and I want to install FreeBSD, Linux, and Windows 95 on them. Here is how I might do it using these hard disks: /dev/wd0 (first physical hard disk) /dev/wd1 (second hard disk) Both disks have 1416 cylinders. I boot from a MS-DOS or Windows 95 boot disk that contains the FDISK.EXE utility and make a small 50 meg primary partition (35-40 for Windows 95, plus a little breathing room) on the first disk. Also create a larger partition on the second hard disk for my Windows applications and data. I reboot and install Windows 95 (easier said than done) on the C: partition. The next thing I do is install Linux. I am not sure about all the distributions of Linux, but slackware includes LILO (see ). When I am partitioning out my hard disk with Linux fdisk, I would put all of Linux on the first drive (maybe 300 megs for a nice root partition and some swap space). After I install Linux, and are prompted about installing LILO, make SURE that I install it on the boot sector of my root Linux partition, not in the MBR (master boot record). The remaining hard disk space can go to FreeBSD. I also make sure that my FreeBSD root slice does not go beyond the 1024th cylinder. (The 1024th cylinder is 528 megs into the disk with our hypothetical 720MB disks). I will use the rest of the hard drive (about 270 megs) for the /usr and / slices if I wish. The rest of the second hard disk (size depends on the amount of my Windows application/data partition that I created in step 1 can go to the /usr/src slice and swap space. When viewed with the Windows 95 fdisk utility, my hard drives should now look something like this: --------------------------------------------------------------------- Display Partition Information Current fixed disk drive: 1 Partition Status Type Volume_Label Mbytes System Usage C: 1 A PRI DOS 50 FAT** 7% 2 A Non-DOS (Linux) 300 43% Total disk space is 696 Mbytes (1 Mbyte = 1048576 bytes) Press Esc to continue --------------------------------------------------------------------- Display Partition Information Current fixed disk drive: 2 Partition Status Type Volume_Label Mbytes System Usage D: 1 A PRI DOS 420 FAT** 60% Total disk space is 696 Mbytes (1 Mbyte = 1048576 bytes) Press Esc to continue --------------------------------------------------------------------- ** May say FAT16 or FAT32 if you are using the OEM SR2 update. See ). Install FreeBSD. I make sure to boot with my first hard disk set at NORMAL in the BIOS. If it is not, I will have the enter my true disk geometry at boot time (to get this, boot Windows 95 and consult Microsoft Diagnostics (MSD.EXE), or check your BIOS) with the parameter hd0=1416,16,63 where 1416 is the number of cylinders on my hard disk, 16 is the number of heads per track, and 63 is the number of sectors per track on the drive. When partitioning out the hard disk, I make sure to install Boot Easy on the first disk. I do not worry about the second disk, nothing is booting off of it. When I reboot, Boot Easy should recognize my three bootable partitions as DOS (Windows 95), Linux, and BSD (FreeBSD). Special Considerations Most operating systems are very picky about where and how they are placed on the hard disk. Windows 95 and DOS need to be on the first primary partition on the first hard disk. OS/2 is the exception. It can be installed on the first or second disk in a primary or extended partition. If you are not sure, keep the beginning of the bootable partitions below the 1024th cylinder. If you install Windows 95 on an existing BSD system, it will destroy the MBR, and you will have to reinstall your previous boot manager. Boot Easy can be reinstalled by using the BOOTINST.EXE utility included in the \TOOLS directory on the CDROM, and via ftp. You can also re-start the installation process and go to the partition editor. From there, mark the FreeBSD partition as bootable, select Boot Manager, and then type W to (W)rite out the information to the MBR. You can now reboot, and Boot Easy should then recognize Windows 95 as DOS. Please keep in mind that OS/2 can read FAT and HPFS partitions, but not FFS (FreeBSD) or EXT2 (Linux) partitions. Likewise, Windows 95 can only read and write to FAT and FAT32 (see ) partitions. FreeBSD can read most - file systems, but currently cannot read HPFS partitions. Linux + filesystems, but currently cannot read HPFS partitions. Linux can read HPFS partitions, but can not write to them. Recent versions of the Linux kernel (2.x) can read and write to Windows 95 VFAT partitions (VFAT is what gives Windows 95 long file names - it is pretty much the same as FAT). Linux can read and - write to most file systems. Got that? I hope so. + write to most filesystems. Got that? I hope so. Examples (section needs work, please send your example to jayrich@sysc.com). FreeBSD+Win95: If you installed FreeBSD after Windows 95, you should see DOS on the Boot Easy menu. This is Windows 95. If you installed Windows 95 after FreeBSD, read above. As long as your hard disk does not have 1024 cylinders you should not have a problem booting. If one of your partitions goes beyond the 1024th cylinder however, and you get messages like invalid system disk under DOS (Windows 95) and FreeBSD will not boot, try looking for a setting in your BIOS called > 1024 cylinder support or NORMAL/LBA mode. DOS may need LBA (Logical Block Addressing) in order to boot correctly. If the idea of switching BIOS settings every time you boot up does not appeal to you, you can boot FreeBSD through DOS via the FBSDBOOT.EXE utility on the CD (It should find your FreeBSD partition and boot it.) FreeBSD+OS/2+Win95: Nothing new here. OS/2's boot manger can boot all of these operating systems, so that should not be a problem. FreeBSD+Linux: You can also use Boot Easy to boot both operating systems. FreeBSD+Linux+Win95: (see ) Other Sources of Help There are many Linux HOW-TOs that deal with multiple operating systems on the same hard disk. The Linux+DOS+Win95+OS2 mini-HOWTO offers help on configuring the OS/2 boot manager, and the Linux+FreeBSD mini-HOWTO might be interesting as well. The Linux-HOWTO is also helpful. The NT Loader Hacking Guide provides good information on multibooting Windows NT, '95, and DOS with other operating systems. ]]> And Hale Landis's How It Works document pack contains some good info on all sorts of disk geometry and booting related topics. You can find it at ftp://fission.dt.wdc.com/pub/otherdocs/pc_systems/how_it_works/allhiw.zip. Finally, do not overlook FreeBSD's kernel documentation on the booting procedure, available in the kernel source distribution (it unpacks to file:/usr/src/sys/i386/boot/biosboot/README.386BSD. Technical Details (Contributed by Randall Hopper, rhh@ct.picker.com) This section attempts to give you enough basic information about your hard disks and the disk booting process so that you can troubleshoot most problems you might encounter when getting set up to boot several operating systems. It starts in pretty basic terms, so you may want to skim down in this section until it begins to look unfamiliar and then start reading. Disk Primer Three fundamental terms are used to describe the location of data on your hard disk: Cylinders, Heads, and Sectors. It is not particularly important to know what these terms relate to except to know that, together, they identify where data is physically on your disk. Your disk has a particular number of cylinders, number of heads, and number of sectors per cylinder-head (a cylinder-head also known nown as a track). Collectively this information defines the physical disk geometry for your hard disk. There are typically 512 bytes per sector, and 63 sectors per track, with the number of cylinders and heads varying widely from disk to disk. Thus you can figure the number of bytes of data that will fit on your own disk by calculating: (# of cylinders) × (# heads) × (63 sectors/track) × (512 bytes/sect) For example, on my 1.6 Gig Western Digital AC31600 EIDE hard disk, that is: (3148 cyl) × (16 heads) × (63 sectors/track) × (512 bytes/sect) which is 1,624,670,208 bytes, or around 1.6 Gig. You can find out the physical disk geometry (number of cylinders, heads, and sectors/track counts) for your hard disks using ATAID or other programs off the net. Your hard disk probably came with this information as well. Be careful though: if you are using BIOS LBA (see ), you can not use just any program to get the physical geometry. This is because many programs (e.g. MSD.EXE or FreeBSD fdisk) do not identify the physical disk geometry; they instead report the translated geometry (virtual numbers from using LBA). Stay tuned for what that means. One other useful thing about these terms. Given 3 numbers—a cylinder number, a head number, and a sector-within-track number—you identify a specific absolute sector (a 512 byte block of data) on your disk. Cylinders and Heads are numbered up from 0, and Sectors are numbered up from 1. For those that are interested in more technical details, information on disk geometry, boot sectors, BIOSes, etc. can be found all over the net. Query Lycos, Yahoo, etc. for boot sector or master boot record. Among the useful info you will find are Hale Landis's How It Works document pack. See the section for a few pointers to this pack. Ok, enough terminology. We are talking about booting here. The Booting Process On the first sector of your disk (Cyl 0, Head 0, Sector 1) lives the Master Boot Record (MBR). It contains a map of your disk. It identifies up to 4 partitions, each of which is a contiguous chunk of that disk. FreeBSD calls partitions slices to avoid confusion with its own partitions, but we will not do that here. Each partition can contain its own operating system. Each partition entry in the MBR has a Partition ID, a Start Cylinder/Head/Sector, and an End Cylinder/Head/Sector. The Partition ID tells what type of partition it is (what OS) and the Start/End tells where it is. lists a smattering of some common Partition IDs. Partition IDs ID (hex) Description 01 Primary DOS12 (12-bit FAT) 04 Primary DOS16 (16-bit FAT) 05 Extended DOS 06 Primary big DOS (> 32MB) 0A OS/2 83 Linux (EXT2FS) A5 FreeBSD, NetBSD, 386BSD (UFS)
Note that not all partitions are bootable (e.g. Extended DOS). Some are—some are not. What makes a partition bootable is the configuration of the Partition Boot Sector that exists at the beginning of each partition. When you configure your favorite boot manager, it looks up the entries in the MBR partition tables of all your hard disks and lets you name the entries in that list. Then when you boot, the boot manager is invoked by special code in the Master Boot Sector of the first probed hard disk on your system. It looks at the MBR partition table entry corresponding to the partition choice you made, uses the Start Cylinder/Head/Sector information for that partition, loads up the Partition Boot Sector for that partition, and gives it control. That Boot Sector for the partition itself contains enough information to start loading the operating system on that partition. One thing we just brushed past that is important to know. All of your hard disks have MBRs. However, the one that is important is the one on the disk that is first probed by the BIOS. If you have only IDE hard disks, its the first IDE disk (e.g. primary disk on first controller). Similarly for SCSI only systems. If you have both IDE and SCSI hard disks though, the IDE disk is typically probed first by the BIOS, so the first IDE disk is the first probed disk. The boot manager you will install will be hooked into the MBR on this first probed hard disk that we have just described. Booting Limitations and Warnings Now the interesting stuff that you need to watch out for. The dreaded 1024 cylinder limit and how BIOS LBA helps The first part of the booting process is all done through the BIOS, (if that is a new term to you, the BIOS is a software chip on your system motherboard which provides startup code for your computer). As such, this first part of the process is subject to the limitations of the BIOS interface. The BIOS interface used to read the hard disk during this period (INT 13H, Subfunction 2) allocates 10 bits to the Cylinder Number, 8 bits to the Head Number, and 6 bits to the Sector Number. This restricts users of this interface (i.e. boot managers hooked into your disk's MBR as well as OS loaders hooked into the Boot Sectors) to the following limits: 1024 cylinders, max 256 heads, max 64 sectors/track, max (actually 63, 0 is not available) Now big hard disks have lots of cylinders but not a lot of heads, so invariably with big hard disks the number of cylinders is greater than 1024. Given this and the BIOS interface as is, you can not boot off just anywhere on your hard disk. The boot code (the boot manager and the OS loader hooked into all bootable partitions' Boot Sectors) has to reside below cylinder 1024. In fact, if your hard disk is typical and has 16 heads, this equates to: 1024 cyl/disk × 16 heads/disk × 63 sect/(cyl-head) × 512 bytes/sector which is around the often-mentioned 528MB limit. This is where BIOS LBA (Logical Block Addressing) comes in. BIOS LBA gives the user of the BIOS API calls access to physical cylinders above 1024 though the BIOS interfaces by redefining a cylinder. That is, it remaps your cylinders and heads, making it appear through the BIOS as though the disk has fewer cylinders and more heads than it actually does. In other words, it takes advantage of the fact that hard disks have relatively few heads and lots of cylinders by shifting the balance between number of cylinders and number of heads so that both numbers lie below the above-mentioned limits (1024 cylinders, 256 heads). With BIOS LBA, the hard disk size limitation is virtually removed (well, pushed up to 8 Gigabytes anyway). If you have an LBA BIOS, you can put FreeBSD or any OS anywhere you want and not hit the 1024 cylinder limit. To use my 1.6 Gig Western Digital as an example again, its physical geometry is: (3148 cyl, 16 heads, 63 sectors/track, 512 bytes/sector) However, my BIOS LBA remaps this to: (787 cyl, 64 heads, 63 sectors/track, 512 bytes/sector) giving the same effective size disk, but with cylinder and head counts within the BIOS API's range (Incidentally, I have both Linux and FreeBSD existing on one of my hard disks above the 1024th physical cylinder, and both operating systems boot fine, thanks to BIOS LBA). Boot Managers and Disk Allocation Another gotcha to watch out when installing boot managers is allocating space for your boot manager. It is best to be aware of this issue up front to save yourself from having to reinstall one or more of your OSs. If you followed the discussion in about the Master Boot Sector (where the MBR is), Partition Boot Sectors, and the booting process, you may have been wondering just exactly where on your hard disk that nifty boot manager is going to live. Well, some boot managers are small enough to fit entirely within the Master Boot Sector (Cylinder 0, Head 0, Sector 0) along with the partition table. Others need a bit more room and actually extend a few sectors past the Master Boot Sector in the Cylinder 0 Head 0 track, since that is typically free…typically. That is the catch. Some operating systems (FreeBSD included) let you start their partitions right after the Master Boot Sector at Cylinder 0, Head 0, Sector 2 if you want. In fact, if you give FreeBSD's sysinstall a disk with an empty chunk up front or the whole disk empty, that is where it will start the FreeBSD partition by default (at least it did when I fell into this trap). Then when you go to install your boot manager, if it is one that occupies a few extra sectors after the MBR, it will overwrite the front of the first partition's data. In the case of FreeBSD, this overwrites the disk label, and renders your FreeBSD partition unbootable. The easy way to avoid this problem (and leave yourself the flexibility to try different boot managers later) is just to always leave the first full track on your disk unallocated when you partition your disk. That is, leave the space from Cylinder 0, Head 0, Sector 2 through Cylinder 0, Head 0, Sector 63 unallocated, and start your first partition at Cylinder 0, Head 1, Sector 1. For what it is worth, when you create a DOS partition at the front of your disk, DOS leaves this space open by default (this is why some boot managers assume it is free). So creating a DOS partition up at the front of your disk avoids this problem altogether. I like to do this myself, creating 1 Meg DOS partition up front, because it also avoids my primary DOS drive letters shifting later when I repartition. For reference, the following boot managers use the Master Boot Sector to store their code and data: OS-BS 1.35 Boot Easy LILO These boot managers use a few additional sectors after the Master Boot Sector: OS-BS 2.0 Beta 8 (sectors 2-5) OS/2's boot manager What if your machine will not boot? At some point when installing boot managers, you might leave the MBR in a state such that your machine will not boot. This is unlikely, but possible when re-FDISKing underneath an already-installed boot manager. If you have a bootable DOS partition on your disk, you can boot off a DOS floppy, and run: A:\> FDISK /MBR to put the original, simple DOS boot code back into the system. You can then boot DOS (and DOS only) off the hard drive. Alternatively, just re-run your boot manager installation program off a bootable floppy.
diff --git a/en_US.ISO8859-1/articles/new-users/article.sgml b/en_US.ISO8859-1/articles/new-users/article.sgml index 53d59d290c..10d678b09b 100644 --- a/en_US.ISO8859-1/articles/new-users/article.sgml +++ b/en_US.ISO8859-1/articles/new-users/article.sgml @@ -1,1056 +1,1056 @@ %man; %mailing-lists; ]>
For People New to Both FreeBSD and Unix Annelise Anderson
andrsn@andrsn.stanford.edu
 August 15, 1997 Congratulations on installing FreeBSD! This introduction is for people new to both FreeBSD and Un*x—so it starts with basics. It assumes you are using version 2.0.5 or later of FreeBSD as distributed by BSDi or FreeBSD.org, your system (for now) has a single user (you)—and you are probably pretty good with DOS/Windows or OS/2. Logging in and Getting Out Log in (when you see login:) as a user you created during installation or as root. (Your FreeBSD installation will already have an account for root; root can go anywhere and do anything, including deleting essential files, so be careful!) The symbols &prompt.user; and &prompt.root; in the following stand for the prompt (yours may be different), with &prompt.user; indicating an ordinary user and &prompt.root; indicating root. To log out (and get a new login: prompt) type &prompt.root; exit as often as necessary. Yes, press enter after commands, and remember that Unix is case-sensitive—exit, not EXIT. To shut down the machine type &prompt.root; /sbin/shutdown -h now Or to reboot type &prompt.root; /sbin/shutdown -r now or &prompt.root; /sbin/reboot You can also reboot with CtrlAltDelete. Give it a little time to do its work. This is equivalent to /sbin/reboot in recent releases of FreeBSD and is much, much better than hitting the reset button. You do not want to have to reinstall this thing, do you? Adding A User with Root Privileges If you did not create any users when you installed the system and are thus logged in as root, you should probably create a user now with &prompt.root; adduser The first time you use adduser, it might ask for some defaults to save. You might want to make the default shell &man.csh.1; instead of &man.sh.1;, if it suggests sh as the default. Otherwise just press enter to accept each default. These defaults are saved in /etc/adduser.conf, an editable file. Suppose you create a user jack with full name Jack Benimble. Give jack a password if security (even kids around who might pound on the keyboard) is an issue. When it asks you if you want to invite jack into other groups, type wheel Login group is ``jack''. Invite jack into other groups: wheel This will make it possible to log in as jack and use the &man.su.1; command to become root. Then you will not get scolded any more for logging in as root. You can quit adduser any time by typing CtrlC, and at the end you will have a chance to approve your new user or simply type n for no. You might want to create a second new user (jill?) so that when you edit jack's login files, you will have a hot spare in case something goes wrong. Once you have done this, use exit to get back to a login prompt and log in as jack. In general, it is a good idea to do as much work as possible as an ordinary user who does not have the power—and risk—of root. If you already created a user and you want the user to be able to su to root, you can log in as root and edit the file /etc/group, adding jack to the first line (the group wheel). But first you need to practice &man.vi.1;, the text editor—or use the simpler text editor, &man.ee.1;, installed on recent version of FreeBSD. To delete a user, use the rmuser command. Looking Around Logged in as an ordinary user, look around and try out some commands that will access the sources of help and information within FreeBSD. Here are some commands and what they do: id Tells you who you are! pwd Shows you where you are—the current working directory. ls Lists the files in the current directory. ls Lists the files in the current directory with a * after executables, a / after directories, and an @ after symbolic links. ls Lists the files in long format—size, date, permissions. ls Lists hidden dot files with the others. If you are root, the dot files show up without the switch. cd Changes directories. cd .. backs up one level; note the space after cd. cd /usr/local goes there. cd ~ goes to the home directory of the person logged in—e.g., /usr/home/jack. Try cd /cdrom, and then ls, to find out if your CDROM is mounted and working. view filename Lets you look at a file (named filename) without changing it. Try view /etc/fstab. :q to quit. cat filename Displays filename on screen. If it is too long and you can see only the end of it, press ScrollLock and use the up-arrow to move backward; you can use ScrollLock with man pages too. Press ScrollLock again to quit scrolling. You might want to try cat on some of the dot files in your home directory—cat .cshrc, cat .login, cat .profile. You will notice aliases in .cshrc for some of the ls commands (they are very convenient). You can create other aliases by editing .cshrc. You can make these aliases available to all users on the system by putting them in the system-wide csh configuration file, /etc/csh.cshrc. Getting Help and Information Here are some useful sources of help. Text stands for something of your choice that you type in—usually a command or filename. apropos text Everything containing string text in the whatis database. man text The man page for text. The major source of documentation for Un*x systems. man ls will tell you all the ways to use the ls command. Press Enter to move through text, CtrlB to go back a page, CtrlF to go forward, q or CtrlC to quit. which text Tells you where in the user's path the command text is found. locate text All the paths where the string text is found. whatis text Tells you what the command text does and its man page. Typing whatis * will tell you about all the binaries in the current directory. whereis text Finds the file text, giving its full path. You might want to try using whatis on some common useful commands like cat, more, grep, mv, find, tar, chmod, chown, date, and script. more lets you read a page at a time as it does in DOS, e.g., ls -l | more or more filename. The * works as a wildcard—e.g., ls w* will show you files beginning with w. Are some of these not working very well? Both &man.locate.1; and &man.whatis.1; depend on a database that is rebuilt weekly. If your machine is not going to be left on over the weekend (and running FreeBSD), you might want to run the commands for daily, weekly, and monthly maintenance now and then. Run them as root and give each one time to finish before you start the next one, for now. &prompt.root; periodic daily output omitted &prompt.root; periodic weekly output omitted &prompt.root; periodic monthly output omitted If you get tired of waiting, press AltF2 to get another virtual console, and log in again. After all, it is a multi-user, multi-tasking system. Nevertheless these commands will probably flash messages on your screen while they are running; you can type clear at the prompt to clear the screen. Once they have run, you might want to look at /var/mail/root and /var/log/messages. Running such commands is part of system administration—and as a single user of a Unix system, you are your own system administrator. Virtually everything you need to be root to do is system administration. Such responsibilities are not covered very well even in those big fat books on Unix, which seem to devote a lot of space to pulling down menus in windows managers. You might want to get one of the two leading books on systems administration, either Evi Nemeth et.al.'s UNIX System Administration Handbook (Prentice-Hall, 1995, ISBN 0-13-15051-7)—the second edition with the red cover; or Æleen Frisch's Essential System Administration (O'Reilly & Associates, 1993, ISBN 0-937175-80-3). I used Nemeth. Editing Text To configure your system, you need to edit text files. Most of them will be in the /etc directory; and you will need to su to root to be able to change them. You can use the easy ee, but in the long run the text editor vi is worth learning. There is an excellent tutorial on vi in /usr/src/contrib/nvi/docs/tutorial if you have that installed; otherwise you can get it by FTP to ftp.cdrom.com in the directory FreeBSD/FreeBSD-current/src/contrib/nvi/docs/tutorial. Before you edit a file, you should probably back it up. Suppose you want to edit /etc/rc.conf. You could just use cd /etc to get to the /etc directory and do: &prompt.root; cp rc.conf rc.conf.orig This would copy rc.conf to rc.conf.orig, and you could later copy rc.conf.orig to rc.conf to recover the original. But even better would be moving (renaming) and then copying back: &prompt.root; mv rc.conf rc.conf.orig &prompt.root; cp rc.conf.orig rc.conf because the mv command preserves the original date and owner of the file. You can now edit rc.conf. If you want the original back, you would then mv rc.conf rc.conf.myedit (assuming you want to preserve your edited version) and then &prompt.root; mv rc.conf.orig rc.conf to put things back the way they were. To edit a file, type &prompt.root; vi filename Move through the text with the arrow keys. Esc (the escape key) puts vi in command mode. Here are some commands: x delete letter the cursor is on dd delete the entire line (even if it wraps on the screen) i insert text at the cursor a insert text after the cursor Once you type i or a, you can enter text. Esc puts you back in command mode where you can type :w to write your changes to disk and continue editing :wq to write and quit :q! to quit without saving changes /text to move the cursor to text; /Enter (the enter key) to find the next instance of text. G to go to the end of the file nG to go to line n in the file, where n is a number CtrlL to redraw the screen Ctrlb and Ctrlf go back and forward a screen, as they do with more and view. Practice with vi in your home directory by creating a new file with vi filename and adding and deleting text, saving the file, and calling it up again. vi delivers some surprises because it is really quite complex, and sometimes you will inadvertently issue a command that will do something you do not expect. (Some people actually like vi—it is more powerful than DOS EDIT—find out about the :r command.) Use Esc one or more times to be sure you are in command mode and proceed from there when it gives you trouble, save often with :w, and use :q! to get out and start over (from your last :w) when you need to. Now you can cd to /etc, su to root, use vi to edit the file /etc/group, and add a user to wheel so the user has root privileges. Just add a comma and the user's login name to the end of the first line in the file, press Esc, and use :wq to write the file to disk and quit. Instantly effective. (You did not put a space after the comma, did you?) Printing Files from DOS At this point you probably do not have the printer working, so here is a way to create a file from a man page, move it to a floppy, and then print it from DOS. Suppose you want to read carefully about changing permissions on files (pretty important). You can use man chmod to read about it. The command &prompt.user; man chmod | col -b > chmod.txt will remove formatting codes and send the man page to the chmod.txt file instead of showing it on your screen. Now put a dos-formatted diskette in your floppy drive a, su to root, and type &prompt.root; /sbin/mount -t msdos /dev/fd0 /mnt to mount the floppy drive on /mnt. Now (you no longer need to be root, and you can type exit to get back to being user jack) you can go to the directory where you created chmod.txt and copy the file to the floppy with: &prompt.user; cp chmod.txt /mnt and use ls /mnt to get a directory listing of /mnt, which should show the file chmod.txt. You might especially want to make a file from /sbin/dmesg by typing &prompt.user; /sbin/dmesg > dmesg.txt and copying dmesg.txt to the floppy. /sbin/dmesg is the boot log record, and it is useful to understand it because it shows what FreeBSD found when it booted up. If you ask questions on the &a.questions; or on a USENET group—like FreeBSD is not finding my tape drive, what do I do?—people will want to know what dmesg has to say. You can now dismount the floppy drive (as root) to get the disk out with &prompt.root; /sbin/umount /mnt and reboot to go to DOS. Copy these files to a DOS directory, call them up with DOS EDIT, Windows Notepad or Wordpad, or a word processor, make a minor change so the file has to be saved, and print as you normally would from DOS or Windows. Hope it works! man pages come out best if printed with the DOS print command. (Copying files from FreeBSD to a mounted DOS partition is in some cases still a little risky.) Getting the printer printing from FreeBSD involves creating an appropriate entry in /etc/printcap and creating a matching spool directory in /var/spool/output. If your printer is on lpt0 (what DOS calls LPT1), you may only need to go to /var/spool/output and (as root) create the directory lpd by typing: mkdir lpd, if it does not already exist. Then the printer should respond if it is turned on when the system is booted, and lp or lpr should send a file to the printer. Whether or not the file actually prints depends on configuring it, which is covered in the FreeBSD handbook. Other Useful Commands df shows file space and mounted systems. ps aux shows processes running. ps ax is a narrower form. rm filename remove filename. rm -R dir removes a directory dir and all subdirectories—careful! ls -R lists files in the current directory and all subdirectories; I used a variant, ls -AFR > where.txt, to get a list of all the files in / and (separately) /usr before I found better ways to find files. passwd to change user's password (or root's password) man hier - man page on the Unix file system + man page on the Unix filesystem Use find to locate filename in /usr or any of its subdirectories with &prompt.user; find /usr -name "filename" You can use * as a wildcard in "filename" (which should be in quotes). If you tell find to search in / instead of /usr it will look for the - file(s) on all mounted file systems, including the CDROM and the + file(s) on all mounted filesystems, including the CDROM and the DOS partition. An excellent book that explains Unix commands and utilities is Abrahams & Larson, Unix for the Impatient (2nd ed., Addison-Wesley, 1996). There is also a lot of Unix information on the Internet. Try the Unix Reference Desk. Next Steps You should now have the tools you need to get around and edit files, so you can get everything up and running. There is a great deal of information in the FreeBSD handbook (which is probably on your hard drive) and FreeBSD's web site. A wide variety of packages and ports are on the CDROM as well as the web site. The handbook tells you more about how to use them (get the package if it exists, with pkg_add /cdrom/packages/All/packagename, where packagename is the filename of the package). The CDROM has lists of the packages and ports with brief descriptions in cdrom/packages/index, cdrom/packages/index.txt, and cdrom/ports/index, with fuller descriptions in /cdrom/ports/*/*/pkg/DESCR, where the *s represent subdirectories of kinds of programs and program names respectively. If you find the handbook too sophisticated (what with lndir and all) on installing ports from the CDROM, here is what usually works: Find the port you want, say kermit. There will be a directory for it on the CDROM. Copy the subdirectory to /usr/local (a good place for software you add that should be available to all users) with: &prompt.root; cp -R /cdrom/ports/comm/kermit /usr/local This should result in a /usr/local/kermit subdirectory that has all the files that the kermit subdirectory on the CDROM has. Next, create the directory /usr/ports/distfiles if it does not already exist using mkdir. Now check check /cdrom/ports/distfiles for a file with a name that indicates it is the port you want. Copy that file to /usr/ports/distfiles; in recent versions you can skip this step, as FreeBSD will do it for you. In the case of kermit, there is no distfile. Then cd to the subdirectory of /usr/local/kermit that has the file Makefile. Type &prompt.root; make all install During this process the port will FTP to get any compressed files it needs that it did not find on the CDROM or in /usr/ports/distfiles. If you do not have your network running yet and there was no file for the port in /cdrom/ports/distfiles, you will have to get the distfile using another machine and copy it to /usr/ports/distfiles from a floppy or your DOS partition. Read Makefile (with cat or more or view) to find out where to go (the master distribution site) to get the file and what its name is. Its name will be truncated when downloaded to DOS, and after you get it into /usr/ports/distfiles you will have to rename it (with the mv command) to its original name so it can be found. (Use binary file transfers!) Then go back to /usr/local/kermit, find the directory with Makefile, and type make all install. The other thing that happens when installing ports or packages is that some other program is needed. If the installation stops with a message can't find unzip or whatever, you might need to install the package or port for unzip before you continue. Once it is installed type rehash to make FreeBSD reread the files in the path so it knows what is there. (If you get a lot of path not found messages when you use whereis or which, you might want to make additions to the list of directories in the path statement in .cshrc in your home directory. The path statement in Unix does the same kind of work it does in DOS, except the current directory is not (by default) in the path for security reasons; if the command you want is in the directory you are in, you need to type ./ before the command to make it work; no space after the slash.) You might want to get the most recent version of Netscape from their FTP site. (Netscape requires the X Window System.) There is now a FreeBSD version, so look around carefully. Just use gunzip filename and tar xvf filename on it, move the binary to /usr/local/bin or some other place binaries are kept, rehash, and then put the following lines in .cshrc in each user's home directory or (easier) in /etc/csh.cshrc, the system-wide csh start-up file: setenv XKEYSYMDB /usr/X11R6/lib/X11/XKeysymDB setenv XNLSPATH /usr/X11R6/lib/X11/nls This assumes that the file XKeysymDB and the directory nls are in /usr/X11R6/lib/X11; if they are not, find them and put them there. If you originally got Netscape as a port using the CDROM (or FTP), do not replace /usr/local/bin/netscape with the new netscape binary; this is just a shell script that sets up the environment variables for you. Instead rename the new binary to netscape.bin and replace the old binary, which is /usr/local/netscape/netscape. Your Working Environment Your shell is the most important part of your working environment. In DOS, the usual shell is command.com. The shell is what interprets the commands you type on the command line, and thus communicates with the rest of the operating system. You can also write shell scripts, which are like DOS batch files: a series of commands to be run without your intervention. Two shells come installed with FreeBSD: csh and sh. csh is good for command-line work, but scripts should be written with sh (or bash). You can find out what shell you have by typing echo $SHELL. The csh shell is okay, but tcsh does everything csh does and more. It allows you to recall commands with the arrow keys and edit them. It has tab-key completion of filenames (csh uses the Esc key), and it lets you switch to the directory you were last in with cd -. It is also much easier to alter your prompt with tcsh. It makes life a lot easier. Here are the three steps for installing a new shell: Install the shell as a port or a package, just as you would any other port or package. Use rehash and which tcsh (assuming you are installing tcsh) to make sure it got installed. As root, edit /etc/shells, adding a line in the file for the new shell, in this case /usr/local/bin/tcsh, and save the file. (Some ports may do this for you.) Use the chsh command to change your shell to tcsh permanently, or type tcsh at the prompt to change your shell without logging in again. It can be dangerous to change root's shell to something other than sh or csh on early versions of FreeBSD and many other versions of Unix; you may not have a working shell when the system puts you into single user mode. The solution is to use su -m to become root, which will give you the tcsh as root, because the shell is part of the environment. You can make this permanent by adding it to your .tcshrc file as an alias with alias su su -m. When tcsh starts up, it will read the /etc/csh.cshrc and /etc/csh.login files, as does csh. It will also read the .login file in your home directory and the .cshrc file as well, unless you provide a .tcshrc file. This you can do by simply copying .cshrc to .tcshrc. Now that you have installed tcsh, you can adjust your prompt. You can find the details in the manual page for tcsh, but here is a line to put in your .tcshrc that will tell you how many commands you have typed, what time it is, and what directory you are in. It also produces a > if you are an ordinary user and a # if you are root, but tsch will do that in any case: set prompt = "%h %t %~ %# " This should go in the same place as the existing set prompt line if there is one, or under "if($?prompt) then" if not. Comment out the old line; you can always switch back to it if you prefer it. Do not forget the spaces and quotes. You can get the .tcshrc reread by typing source .tcshrc. You can get a listing of other environmental variables that have been set by typing env at the prompt. The result will show you your default editor, pager, and terminal type, among possibly many others. A useful command if you log in from a remote location and can not run a program because the terminal is not capable is setenv TERM vt100. Other As root, you can dismount the CDROM with /sbin/umount /cdrom, take it out of the drive, insert another one, and mount it with /sbin/mount_cd9660 /dev/cd0a /cdrom assuming cd0a is the device name for your CDROM drive. The most recent versions of FreeBSD let you mount the CDROM with just /sbin/mount /cdrom. - Using the live file system—the second of FreeBSD's + Using the live filesystem—the second of FreeBSD's CDROM disks—is useful if you have got limited space. What - is on the live file system varies from release to release. You + is on the live filesystem varies from release to release. You might try playing games from the CDROM. This involves using lndir, which gets installed with the X Window System, to tell the program(s) where to find the necessary files, because they are in the /cdrom file system instead of in /usr and its subdirectories, which is where they are expected to be. Read man lndir. Comments Welcome If you use this guide I would be interested in knowing where it was unclear and what was left out that you think should be included, and if it was helpful. My thanks to Eugene W. Stark, professor of computer science at SUNY-Stony Brook, and John Fieber for helpful comments. Annelise Anderson, andrsn@andrsn.stanford.edu
diff --git a/en_US.ISO8859-1/articles/solid-state/article.sgml b/en_US.ISO8859-1/articles/solid-state/article.sgml index 8467072ba9..567fc8132e 100644 --- a/en_US.ISO8859-1/articles/solid-state/article.sgml +++ b/en_US.ISO8859-1/articles/solid-state/article.sgml @@ -1,630 +1,630 @@ %man; ]>
FreeBSD and Solid State Devices John Kozubik
john@kozubik.com
 $FreeBSD$ 2001 The FreeBSD Documentation Project &legalnotice; This article covers the use of solid state disk devices in FreeBSD to create embedded systems. Embedded systems have the advantage of increased stability due to the lack of integral moving parts (hard drives). Account must be taken, however, for the generally low disk space available in the system and the durability of the storage medium. Specific topics to be covered include the types and attributes of solid state media suitable for disk use in FreeBSD, kernel options that are of interest in such an environment, the rc.diskless mechanisms that automate the initialization of such systems and the need for read-only filesystems, - and building file systems from scratch. The article will conclude + and building filesystems from scratch. The article will conclude with some general strategies for small and read-only FreeBSD environments. Solid State Disk Devices The scope of this article will be limited to solid state disk devices made from flash memory. Flash memory is a solid state memory (no moving parts) that is non-volatile (the memory maintains data even after all power sources have been disconnected). Flash memory can withstand tremendous physical shock and is reasonably fast (the flash memory solutions covered in this article are slightly slower than a EIDE hard disk for write operations, and much faster for read operations). One very important aspect of flash memory, the ramifications of which will be discussed later in this article, is that each sector has a limited rewrite capacity. You can only write, erase, and write again to a sector of flash memory a certain number of times before the sector becomes permanently unusable. Although many flash memory products automatically map bad blocks, and although some even distribute write operations evenly throughout the unit, the fact remains that there exists a limit to the amount of writing that can be done to the device. Competitive units have between 1,000,000 and 10,000,000 writes per sector in their specification. This figure varies due to the temperature of the environment. Specifically, we will be discussing ATA compatible compact-flash units and the M-Systems Disk-On-Chip flash memory unit. ATA compatible compact-flash cards are quite popular as storage media for digital cameras. Of particular interest is the fact that they pin out directly to the IDE bus and are compatible with the ATA command set. Therefore, with a very simple and low-cost adaptor, these devices can be attached directly to an IDE bus in a computer. Once implemented in this manner, operating systems such as FreeBSD see the device as a normal hard disk (albeit small). The M-Systems Disk-On-Chip product is based on the same underlying flash memory technology as ATA compatible compact-flash cards, but resides in a DIP form factor and is not ATA compatible. To use such a device, not only must you install it on a motherboard that has a Disk-On-Chip socket, you must also build the `fla` driver into any FreeBSD kernel you wish to use it with. Further, there is critical, manufacturer-specific data residing in the boot sector of this device, so you must take care not to install the FreeBSD (or any other) boot loader when using this. Other solid state disk solutions do exist, but their expense, obscurity, and relative unease of use places them beyond the scope of this article. Kernel Options A few kernel options are of specific interest to those creating an embedded FreeBSD system. First, all embedded FreeBSD systems that use flash memory as system disk will be interested in memory disks and memory filesystems. Because of the limited number of writes that can be done to flash memory, the disk and the filesystems no the disk will most likely be mounted read-only. In this environment, filesystems such as /tmp and /var are mounted as memory filesystems to allow the system to create logs and update counters and temporary files. Memory filesystems are a critical component to a successful solid state FreeBSD implementation. You should make sure the following lines exist in your kernel configuration file: options MFS # Memory Filesystem options MD_ROOT # md device usable as a potential root device pseudo-device md # memory disk Second, if you will be using the M-Systems Disk-On-Chip product, you must also include this line: device fla0 at isa? <filename>rc.diskless</filename> and Read-Only Filesystems The post-boot initialization of an embedded FreeBSD system is controlled by /etc/rc.diskless2 (/etc/rc.diskless1 is for BOOTP diskless boot). This initialization script is invoked by placing a line in /etc/rc.conf as follows: diskless_mount=/etc/rc.diskless2 rc.diskless2 mounts /var as a memory filesystem, makes a configurable list of directories in /var with the &man.mkdir.1; command, changes modes on some of those directories, and extracts a list of device entries to copy to a writable (again, a memory filesystem) /dev partition. In the execution of /etc/rc.diskless2, one other rc.conf variable comes into play - varsize. The /etc/rc.diskless2 file creates a /var partition based on the value of this variable in rc.conf: varsize=8192 Remember that this value is in sectors. The creation of the /dev partition by /etc/rc.diskless2, however, is governed by a hard-coded value of 4096 sectors. It is trivial to change this entry in the /etc/rc.diskless2 file itself, although you should not need more space than that for /dev. It is important to remember that the /etc/rc.diskless2 script assumes that you have already removed your conventional /tmp partition and replaced it with a symbolic link to /var/tmp. Because tmp is one of the directories created in /var by the /etc/rc.diskless2 - script, and because /var is a memory file system + script, and because /var is a memory filesystem (which is mounted read-write), /tmp will now be a directory that is read-write as well. The fact that /var and /dev are read-write filesystems is an important distinction, as the / partition (and any other partitions you may have on your flash media) should be mounted read-only. Remember that in we detailed the limitations of flash memory - specifically the limited write capability. The importance of not mounting filesystems on flash media read-write, and the importance of not using a swap file cannot be overstated. A swap file on a busy system can burn through a piece of flash media in less than one year. Heavy logging or temporary file creation and destruction can do the same. Therefore, in addition to removing the swap and /proc entries from your /etc/fstab file, you should also change the Options field for each filesystem to ro as follows: # Device Mountpoint FStype Options Dump Pass# /dev/ad0s1a / ufs ro 1 1 A few applications in the average system will immediately begin to fail as a result of this change. For instance, ports will not install from the ports tree because the /var/db/port.mkversion file does not exist. cron will not run properly as a result of missing cron tabs in the /var created by /etc/rc.diskless2, and syslog and dhcp will encounter problems as well as a result of the read-only filesystem and missing items in the /var that /etc/rc.diskless2 has created. These are only temporary problems though, and are addressed, along with solutions to the execution of other common software packages in . An important thing to remember is that a filesystem that was mounted read-only with /etc/fstab can be made read-write at any time by issuing the command: &prompt.root; /sbin/mount -uw partition and can be toggled back to read-only with the command: &prompt.root; /sbin/mount -ur partition Building a File System From Scratch Because ATA compatible compact-flash cards are seen by FreeBSD as normal IDE hard drives, as is a M-Systems Disk-On-Chip product (when you are running a kernel with the fla driver built in) you could theoretically install FreeBSD from the network using the kern and mfsroot floppies or from a CD. Other than the fact that you should not write a boot-loader of any kind to the M-Systems device, no special instructions are needed. However, even a small installation of FreeBSD using normal installation procedures can produce a system in size of greater than 200 megabytes. Because most people will be using smaller flash memory devices (128 megabytes is considered fairly large - 32 or even 16 megabytes is common) an installation using normal mechanisms is not possible—there is simply not enough disk space for even the smallest of conventional installations. The easiest way to overcome this space limitation is to install FreeBSD using conventional means to a normal hard disk. After the installation is complete, pare down the operating system to a size that will fit onto your flash media, then tar the entire filesystem. The following steps will guide you through the process of preparing a piece of flash memory for your tarred filesystem. Remember, because a normal installation is not being performed, operations such as partitioning, labeling, file-system creation, etc. need to be performed by hand. In addition to the kern and mfsroot floppy disks, you will also need to use the fixit floppy. If you are using a M-Systems Disk-On-Chip, the kernel on your kern floppy must have the fla option detailed in compiled into it. Please see for instructions on creating a new kernel for kern.flp. Partitioning your flash media device After booting with the kern and mfsroot floppies, choose custom from the installation menu. In the custom installation menu, choose partition. In the partition menu, you should delete all existing partitions using the d key. After deleting all existing partitions, create a partition using the c key and accept the default value for the size of the partition. When asked for the type of the partition, make sure the value is set to 165. Now write this partition table to the disk by pressing the w key (this is a hidden option on this screen). When presented with a menu to choose a boot manager, take care to select None if you are using an M-Systems Disk-On-Chip. If you are using a ATA compatible compact flash card, you should choose the FreeBSD Boot Manager. Now press the q key to quit the partition menu. You will be shown the boot manager menu once more - repeat the choice you made earlier. - Creating file systems on your flash memory device + Creating filesystems on your flash memory device Exit the custom installation menu, and from the main installation menu choose the fixit option. After entering the fixit environment, enter the following commands: ATA compatible Disk-On-Chip &prompt.root; mknod /dev/ad0a c 116 0 &prompt.root; mknod /dev/ad0c c 116 2 &prompt.root; disklabel -e /dev/ad0c &prompt.root; mknod /dev/fla0a c 102 0 &prompt.root; mknod /dev/fla0c c 102 2 &prompt.root; disklabel -e /dev/fla0c At this point you will have entered the vi editor under the auspices of the disklabel command. If you are using Disk-On-Chip, the first step will be to change the type value near the beginning of the file from ESDI to DOC2K. Next, regardless of whether you are using Disk-On-Chip or ATA compatible compact flash media, you need to add an a: line at the end of the file. This a: line should look like: a: 123456 0 4.2BSD 0 0 Where 123456 is a number that is exactly the same as the number in the existing c: entry for size. Basically you are duplicating the existing c: line as an a: line, making sure that fstype is 4.2BSD. Save the file and exit. ATA compatible Disk-On-Chip &prompt.root; disklabel -B -r /dev/ad0c &prompt.root; newfs /dev/ad0a &prompt.root; disklabel -B -r /dev/fla0c &prompt.root; newfs /dev/fla0a Placing your filesystem on the flash media Mount the newly prepared flash media: ATA compatible Disk-On-Chip &prompt.root; mount /dev/ad0a /flash &prompt.root; mount /dev/fla0a /flash Bring this machine up on the network so we may transfer our tar file and explode it onto our flash media filesystem. One example of how to do this is: &prompt.root; ifconfig xl0 192.168.0.10 netmask 255.255.255.0 &prompt.root; route add default 192.168.0.1 Now that the machine is on the network, transfer your tar file. You may be faced with a bit of a dilemma at this point - if your flash memory part is 128 megabytes, for instance, and your tar file is larger than 64 megabytes, you cannot have your tar file on the flash media at the same time as you explode it - you will run out of space. One solution to this problem, if you are using FTP, is to untar the file while it is transferred over FTP. If you perform your transfer in this manner, you will never have the tar file and the tar contents on your disk at the same time: ftp> get tarfile.tar "| tar xvf -" If your tarfile is gzipped, you can accomplish this as well: ftp> get tarfile.tar "| zcat | tar xvf -" After the contents of your tarred filesystem are on your flash - memory file system, you can unmount the flash memory and + memory filesystem, you can unmount the flash memory and reboot: &prompt.root; cd / &prompt.root; umount /flash &prompt.root; exit Assuming that you configured your filesystem correctly when it was built on the normal hard disk (with your filesystems mounted read-only, and with the necessary options compiled into the kernel) you should now be successfully booting your FreeBSD embedded system. Building a <filename>kern.flp</filename> Installation Floppy with the fla Driver This section of the article is relevant only to those using M-Systems Disk-On-Chip flash media. It is possible that your kern.flp boot floppy does not have a kernel with the fla driver compiled into it necessary for the system to recognize the Disk-On-Chip. If you have booted off of the installation floppies and are told that no disks are present, then you are probably lacking the fla driver in your kernel. After you have built a kernel with fla support that is smaller than 1.4 megabytes, you can create a custom kern.flp floppy image with it by following these instructions: Obtain an existing kern.flp image file &prompt.root; vnconfig vn0c kern.flp &prompt.root; mount /dev/vn0c /mnt Place your kernel file into /mnt, replacing the existing one &prompt.root; vnconfig -d vn0c Your kern.flp file now has your new kernel on it. System Strategies for Small and Read Only Environments In , it was pointed out that the /var filesystem constructed by /etc/rc.diskless2 and the presence of a read-only root filesystem causes problems with many common software packages used with FreeBSD. In this article, suggestions for successfully running cron, syslog, ports installations, and the Apache web server will be provided. cron In /etc/rc.diskless2 there is a variable named var_dirs. This variable consists of a space-delimited list of directories that will be created inside of /var after it is mounted as a memory filesystem. cron and cron/tabs are not in that list, and without those directories, cron will complain. By inserting cron, cron/tabs, and perhaps even at, and at/jobs as elements of that variable, you will facilitate the running of the &man.cron.8; and &man.at.1; daemons. However, this still does not solve the problem of maintaining cron tabs across reboots. When the system reboots, the /var filesystem that is in memory will disappear and any cron tabs you may have had in it will also disappear. Therefore, one solution would be to create cron tabs for the users that need them, mount your / filesystem as read-write and copy those cron tabs to somewhere safe, like /etc/tabs, then add a line to the end of /etc/rc.diskless2 that copies those crontabs into /var/cron/tabs after that directory has been created during system initialization. You may also need to add a line that changes modes and permissions on the directories you create and the files you copy with /etc/rc.diskless2. syslog syslog.conf specifies the locations of certain log files that exist in /var/log. These files are not created by /etc/rc.diskless2 upon system initialization. Therefore, somewhere in /etc/rc.diskless2, after the section that creates the directories in /var, you will need to add something like this: &prompt.root; touch /var/log/security /var/log/maillog /var/log/cron /var/log/messages &prompt.root; chmod 0644 /var/log/* You will also need to add the log directory to the list of directories that /etc/rc.diskless2 creates. ports installation Before discussing the changes necessary to successfully use the ports tree, a reminder is necessary regarding the read-only nature of your filesystems on the flash media. Since they are read-only, you will need to temporarily mount them read-write using the mount syntax shown in . You should always remount those filesystems read-only when you are done with any maintenance - it is dangerous to leave them in read-write mode lest a process begin logging or otherwise writing regularly to the flash media and wearing it out over time. To make it possible to enter a ports directory and successfully run make install, it is necessary for the file /var/db/port.mkversion to exist, and that it have a correct date in it. Further, we must create a packages directory on a non-memory filesystem that will keep track of our packages across reboots. Because it is necessary to mount your filesystems as read-write for the installation of a package anyway, it is sensible to assume that an area on the flash media can also be used for package information to be written to. First, create a package database directory. This is normally in /var/db/pkg, but we cannot place it there as it will disappear every time the system is booted. &prompt.root; mkdir /etc/pkg Now, add a line to /etc/rc.diskless2 that links the /etc/pkg directory to /var/db/pkg. An example: &prompt.root; ln -s /etc/pkg /var/db/pkg Add another line in /etc/rc.diskless2 that creates and populates /var/db/port.mkversion &prompt.root; touch /var/db/port.mkversion &prompt.root; chmod 0644 /var/db/port.mkversion &prompt.root; echo 20010412 >> /var/db/port.mkversion where 20010412 is a date that is appropriate for your particular release of FreeBSD - Now, any time that you mount your file systems as read-write and + Now, any time that you mount your filesystems as read-write and install a package, the make install will work because it finds a suitable /var/db/port.mkversion, and package information will be written successfully to /etc/pkg (because the filesystem will, at that time, be mounted read-write) which will always be available to the operating system as /var/db/pkg. Apache Web Server Apache keeps pid files and logs in apache_install/logs. - Since this directory no doubt exists on a read-only file system, this + Since this directory no doubt exists on a read-only filesystem, this will not work. It is necessary to add a new directory to the /etc/rc.diskless2 list of directories to create in /var, to link apache_install/logs to /var/log/apache. It is also necessary to set permissions and ownership on this new directory. First, add the directory log/apache to the list of directories to be created in /etc/rc.diskless2. Second, add these commands to /etc/rc.diskless2 after the directory creation section: &prompt.root; chmod 0774 /var/log/apache &prompt.root; chown nobody:nobody /var/log/apache Finally, remove the existing apache_install/logs directory, and replace it with a link: &prompt.root; rm -rf (apache_install)/logs &prompt.root; ln -s /var/log/apache (apache_install)/logs
diff --git a/en_US.ISO8859-1/articles/vinum/article.sgml b/en_US.ISO8859-1/articles/vinum/article.sgml index 82029c95db..3c31dce251 100644 --- a/en_US.ISO8859-1/articles/vinum/article.sgml +++ b/en_US.ISO8859-1/articles/vinum/article.sgml @@ -1,2542 +1,2542 @@ Vinum"> %man; ]>
Bootstrapping Vinum: A Foundation for Reliable Servers Robert A. Van Valzah 2001 Robert A. Van Valzah - $Date: 2002-02-28 02:55:01 $ GMT - $Id: article.sgml,v 1.6 2002-02-28 02:55:01 keramida Exp $ + $Date: 2002-05-16 01:42:03 $ GMT + $Id: article.sgml,v 1.7 2002-05-16 01:42:03 trhodes Exp $ In the most abstract sense, these instructions show how to build a pair of disk drives where either one is adequate to keep your server running if the other fails. Life is better if they are both working, but your server will never die unless both disk drives die at once. If you choose ATAPI drives and use a fairly generic kernel, you can be confident that either of these drives can be plugged into most any main board to produce a working server in a pinch. The drives need not be identical. These techniques work equally well with SCSI drives as they do with ATAPI, but I will focus on ATAPI here because main boards with this interface are ubiquitous. After building the foundation of a reliable server as shown here, you can expand to as many disk drives as necessary to build the failure-resilient server of your dreams.
Introduction Any machine that is going to provide reliable service needs to have either redundant components on-line or a pool of off-line spares that can be promptly swapped in. Commodity PC hardware makes it affordable for even small organizations to have some spare parts available that could be pressed into service following the failure of production equipment. In many organizations, a failed power supply, NIC, memory, or main board could easily be swapped with a standby in a matter of minutes and be ready to return to production work. If a disk drive fails, however, it often has to be restored from a tape backup. This may take many hours. With disk drive capacities rising faster than tape drive capacities, the time needed to restore a failed disk drive seems to increase as technology progresses. &vinum.ap; is a volume manager for FreeBSD that provides a standard block - I/O layer interface to the file system code just as any hardware + I/O layer interface to the filesystem code just as any hardware device driver would. It works by managing partitions of type vinum and allows you to subdivide and group the space in such partitions into logical devices called volumes that can be used in the same way as disk partitions. Volumes can be configured for resilience, performance, or both. Experienced system administrators will immediately recognize the benefits - of being able to configure each file system to match the way + of being able to configure each filesystem to match the way it is most often used. In some ways, Vinum is similar to &man.ccd.4;, but it is far more flexible and robust in the face of failures. It is only slightly more difficult to set up than &man.ccd.4;. &man.ccd.4; may meet your needs if you are only interested in concatenation.
Terminology Discussion of storage management can get very tricky simply because of the terminology involved. As we will see below, the terms disk, slice, partition, subdisk, and volume each refer to different things that present the same interface to a kernel function like swapping. The potential for confusion is compounded because the objects that these terms represent can be nested inside each other. I will refer to a physical disk drive as a spindle. A partition here means a BSD partition as maintained by disklabel. It does not refer to slices or BIOS partitions as maintained by fdisk.
Vinum Objects Vinum defines a hierarchy of four objects that it uses to manage storage (see ). Different combinations of these objects are used to achieve failure resilience, performance, and/or extra capacity. I will give a whirlwind tour of the objects here--see the Vinum web site for a more thorough description.
Vinum Objects and Architecture +-----+------+------+ | UFS | swap | Etc. | +---+-+------+----+ + | volume | | + V +-------------+ + | i plex | | + n +-------------+ + | u subdisk | | + m +-------------+ + | drive | | +-----------------+ + | Block I/O devices | +-------------------+ Vinum Objects and Architecture
The top object, a vinum volume, implements a virtual disk that provides a standard block I/O layer interface to other parts of the kernel. The bottom object, a vinum drive, uses this same interface to request I/O from physical devices below it. In between these two (from top to bottom) we have objects called a vinum plex and a vinum subdisk. As you can probably guess from the name, a vinum subdisk is a contiguous subset of the space available on a vinum drive. It lets you subdivide a vinum drive in much the same way that a disk BSD partition lets you subdivide a BIOS slice. A plex allows subdisks to be grouped together making the space of all subdisks available as a single object. A plex can be organized with its constituent subdisks concatenated or striped. Both organizations are useful for spreading I/O requests across spindles since plexes reside on distinct spindles. A striped plex will switch spindles each time a multiple of the stripe size is reached. A concatenated plex will switch spindles only when the end of a subdisk is reached. An important characteristic of a Vinum volume is that it can be made up of more than one plex. In this case, writes go to all plexes and a read may be satisfied by any plex. Configuring two or more plexes on distinct spindles yields a volume that is resilient to failure. Vinum maintains a configuration that defines instances of the above objects and the way they are related to each other. This configuration is automatically written to all spindles under Vinum management whenever it changes.
Vinum Volume/Plex Organization Although Vinum can manage any number of spindles, I will only cover scenarios with two spindles here for simplification. See to see how two spindles organized with Vinum compare to two spindles without Vinum. Characteristics of Two Spindles Organized with Vinum Organization Total Capacity Failure Resilient Peak Read Performance Peak Write Performance Concatenated Plexes Unchanged, but appears as a single drive No Unchanged Unchanged Striped Plexes (RAID-0) Unchanged, but appears as a single drive No 2x 2x Mirrored Volumes (RAID-1) 1/2, appearing as a single drive Yes 2x Unchanged
shows that striping yields the same capacity and lack of failure resilience as concatenation, but it has better peak read and write performance. Hence we will not be using concatenation in any of the examples here. Mirrored volumes provide the benefits of improved peak read performance and failure resilience--but this comes at a loss in capacity. Both concatenation and striping bring their benefits over a single spindle at the cost of increased likelihood of failure since more than one spindle is now involved. When three or more spindles are present, Vinum also supports rotated, block-interleaved parity (also called RAID-5) that provides better capacity than mirroring (but not quite as good as striping), better read performance than both mirroring and striping, and good failure resilience. There is, however, a substantial decrease in write performance with RAID-5. Most of the benefits become more pronounced with five or more spindles. The organizations described above may be combined to provide benefits that no single organization can match. For example, mirroring and striping can be combined to provide failure-resilience with very fast read performance.
Vinum History Vinum is a standard part of even a "minimum" FreeBSD distribution and it has been standard since 3.0-RELEASE. The official pronunciation of the name is VEE-noom. &vinum.ap; was inspired by the Veritas Volume Manager, but was not derived from it. The name is a play on that history and the Latin adage In Vino Veritas (Vino is the accusative form of Vinum). Literally translated, that is Truth lies in wine hinting that drunkards have a hard time lying. I have been using it in production on six different servers for over two years with no data loss. Like the rest of FreeBSD, Vinum provides rock-stable performance. (On a personal note, I have seen Vinum panic when I misconfigured something, but I have never had any trouble in normal operation.) Greg Lehey wrote Vinum for FreeBSD, but he is seeking help in porting it to NetBSD and OpenBSD. Just like the rest of FreeBSD, Vinum is undergoing continuous development. Several subtle, but significant bugs have been fixed in recent releases. It is always best to use the most recent code base that meets your stability requirements.
Vinum Deployment Strategy Vinum, coupled with prudent partition management, lets you keep warm-spare spindles on-line so that failures are transparent to users. Failed spindles can be replaced during regular maintenance periods or whenever it is convenient. When all spindles are working, the server benefits from increased performance and capacity. Having redundant copies of your home directory does not help you if the spindle holding root, /usr, or swap fails on your server. Hence I focus here on building a simple foundation for a failure-resilient server covering the root, /usr, /home, and swap partitions. Vinum mirroring does not remove the need for making backups! Mirroring cannot help you recover from site disasters or the dreaded rm -r -f / command.
Why Bootstrap Vinum? It is possible to add Vinum to a server configuration after it is already in production use, but this is much harder than designing for it from the start. Ironically, Vinum is not supported by /stand/sysinstall and hence you cannot install /usr right onto a Vinum volume. Vinum currently does not - support the root file system (this feature + support the root filesystem (this feature is in development). Hence it is a bit tricky to get started using Vinum, but these instructions take you though the process of planning for Vinum, installing FreeBSD without it, and then beginning to use it. I have come to call this whole process bootstrapping Vinum. That is, the process of getting Vinum initially installed and operating to the point where you have met your resilience or performance goals. My purpose here is to document a Vinum bootstrapping method that I have found that works well for me.
Vinum Benefits The server foundation scenario I have chosen here allows me to show you examples of configuring for resilience on /usr and /home. Yet Vinum provides benefits other than resilience--namely performance, capacity, and manageability. It can significantly improve disk performance (especially under multi-user loads). Vinum can easily concatenate many smaller disks to produce the illusion of a single larger disk (but my server foundation scenario does not allow me to illustrate these benefits here). For servers with many spindles, Vinum provides substantial benefits in volume management, particularly when coupled with hot-pluggable hardware. Data can be moved from spindle to spindle while the system is running without loss of production time. Again, details of this will not be given here, but once you get your feet wet with Vinum, other documentation will help you do things like this. See "The Vinum Volume Manager" for a technical introduction to Vinum, &man.vinum.8; for a description of the vinum command, and &man.vinum.4; for a description of the vinum device driver and the way Vinum objects are named. Breaking up your disk space into smaller and smaller partitions has the benefit of allowing you to tune for the most common type of access and tends to keep disk hogs within their pens. However it also causes some loss in total available disk space due to fragmentation.
Server Operation in Degraded Mode Some disk failures in this two-spindle scenario will result in Vinum automatically routing all disk I/O to the remaining good spindle. Others will require brief manual intervention on the console to configure the server for degraded mode operation and a quick reboot. Other than actual hardware repairs, most recovery work can be done while the server is running in multi-user degraded mode so there is as little production impact from failures as possible. I give the instructions in needed to configure the server for degraded mode operation in those cases where Vinum cannot do it automatically. I also give the instructions needed to return to normal operation once the failed hardware is repaired. You might call these instructions Vinum failure recovery techniques. I recommend practicing using these instructions by recovering from simulated failures. For each failure scenario, I also give tips below for simulating a failure even when your hardware is working well. Even a minimum Vinum system as described in below can be a good place to experiment with recovery techniques without impacting production equipment.
Hardware RAID vs. Vinum (Software RAID) Manual intervention is sometimes required to configure a server for degraded mode because Vinum is implemented in software that runs after the FreeBSD kernel is loaded. One disadvantage of such software RAID solutions is that there is nothing that can be done to hide spindle failures from the BIOS or the FreeBSD boot sequence. Hence the manual reconfiguration of the server for degraded operation mentioned above just informs the BIOS and boot sequence of failed spindles. Hardware RAID solutions generally have an advantage in that they require no such reconfiguration since spindle failures are hidden from the BIOS and boot sequence. Hardware RAID, however, may have some disadvantages that can be significant in some cases: The hardware RAID controller itself may become a single point of failure for the system. The data is usually kept in a proprietary format so that a disk drive cannot be simply plugged into another main board and booted. You often cannot mix and match drives with different sizes and interfaces. You are often limited to the number of drives supported by the hardware RAID controller (often only four or eight). In other words, &vinum.ap; may offer advantages in that there is no single point of failure, the drives can boot on most any main board, and you are free to mix and match as many drives using whatever interface you choose. Keep your kernel fairly generic (or at least keep /kernel.GENERIC around). This will improve the chances that you can come back up on foreign hardware more quickly. The pros and cons discussed above suggest - that the root file system and swap partition are good + that the root filesystem and swap partition are good candidates for hardware RAID if available. This is especially true for servers where it is difficult for administrators to get console access (recall that this is sometimes required to configure a server for degraded mode operation). A server with only software RAID is well suited to office and home environments where an administrator can be close at hand. A common myth is that hardware RAID is always faster than software RAID. Since it runs on the host CPU, Vinum often has more CPU power and memory available than a dedicated RAID controller would have. If performance is a prime concern, it is best to benchmark your application running on your CPU with your spindles using both hardware and software RAID systems before making a decision.
Hardware for Vinum These instructions may be timely since commodity PC hardware can now easily host several hundred gigabytes of reasonably high-performance disk space at a low price. Many disk drive manufactures now sell 7,200 RPM disk drives with quite low seek times and high transfer rates through ATA-100 interfaces, all at very attractive prices. Four such drives, attached to a suitable main board and configured with Vinum and prudent partitioning, yields a failure-resilient, high performance disk server at a very reasonable cost. However, you can indeed get started with Vinum very simply. A minimum system can be as simple as an old CPU (even a 486 is fine) and a pair of drives that are 500 MB or more. They need not be the same size or even use the same interface (i.e., it is fine to mix ATAPI and SCSI). So get busy and give this a try today! You will have the foundation of a failure-resilient server running in an hour or so!
Bootstrapping Phases Greg Lehey suggested this bootstrapping method. It uses knowledge of how Vinum internally allocates disk space to avoid copying data. Instead, Vinum objects are configured so that they occupy the same disk space where /stand/sysinstall built - file systems. - The file systems are thus embedded within + filesystems. + The filesystems are thus embedded within Vinum objects without copying. There are several distinct phases to the Vinum bootstrapping procedure. Each of these phases is presented in a separate section below. The section starts with a general overview of the phase and its goals. It then gives example steps for the two-spindle scenario presented here and advice on how to adapt them for your server. (If you are reading for a general understanding of Vinum bootstrapping, the example sections for each phase can safely be skipped.) The remainder of this section gives an overview of the entire bootstrapping process. Phase 1 involves planning and preparation. We will balance requirements for the server against available resources and make design tradeoffs. We will plan the transition from no Vinum to Vinum on just one spindle, to Vinum on two spindles. In phase 2, we will install a minimum FreeBSD system on a single spindle using partitions of type - 4.2BSD (regular UFS file systems). + 4.2BSD (regular UFS filesystems). - Phase 3 will embed the non-root file systems from phase 2 in + Phase 3 will embed the non-root filesystems from phase 2 in Vinum objects. Note that Vinum will be up and running at this point, but it cannot yet provide any resilience since it only has one spindle on which to store data. Finally in phase 4, we configure Vinum - on a second spindle and make a backup copy of the root file system. - This will give us resilience on all file systems. + on a second spindle and make a backup copy of the root filesystem. + This will give us resilience on all filesystems.
Bootstrapping Phase 1: Planning and Preparation Our goal in this phase is to define the different partitions we will need and examine their requirements. We will also look at available disk drives and controllers and allocate partitions to them. Finally, we will determine the size of each partition and its use during the bootstrapping process. After this planning is complete, we can optionally prepare to use some tools that will make bootstrapping Vinum easier. Several key questions must be answered in this planning phase: - What file system and partitions will be needed? + What filesystem and partitions will be needed? How will they be used? How will we name each spindle? How will the partitions be ordered for each spindle? How will partitions be assigned to the spindles? How will partitions be configured? Resilience or performance? What technique will be used to achieve resilience? What spindles will be used? How will they be configured on the available controllers? How much space is required for each partition?
Phase 1 Example In this example, I will assume a scenario where we are building a minimal foundation for a failure-resilient server. Hence we will need at least root, /usr, /home, and swap partitions. The root, /usr, and - /home file systems all need resilience since the + /home filesystems all need resilience since the server will not be much good without them. The swap partition needs performance first and generally does not need resilience since nothing it holds needs to be retained across a reboot.
Spindle Naming The kernel would refer to the master spindle on the primary and secondary ATA controllers as /dev/ad0 and /dev/ad2 respectively. This assumes that you have not removed the line options ATA_STATIC_ID from your kernel configuration. But Vinum also needs to have a name for each spindle that will stay the same name regardless of how it is attached to the CPU (i.e., if the drive moves, the Vinum name moves with the drive). Some recovery techniques documented below suggest moving a spindle from the secondary ATA controller to the primary ATA controller. (Indeed, the flexibility of making such moves is a key benefit of Vinum especially if you are managing a large number of spindles.) After such a drive/controller swap, the kernel will see what used to be /dev/ad2 as /dev/ad0 but Vinum will still call it by whatever name it had when it was attached to /dev/ad2 (i.e., when it was created or first made known to Vinum). Since connections can change, it is best to give each spindle a unique, abstract name that gives no hint of how it is attached. Avoid names that suggest a manufacturer, model number, physical location, or membership in a sequence (e.g. avoid names like upper, lower, etc., alpha, beta, etc., SCSI1, SCSI2, etc., or Seagate1, Seagate2 etc.). Such names are likely to lose their uniqueness or get out of sequence someday even if they seem like great names today. Once you have picked names for your spindles, label them with a permanent marker. If you have hot-swappable hardware, write the names on the sleds in which the spindles are mounted. This will significantly reduce the likelihood of error when you are moving spindles around later as part of failure recovery or routine system management procedures. In the instructions that follow, Vinum will name the root spindle YouCrazy and the rootback spindle UpWindow. I will only use /dev/ad0 when I want to refer to whichever of the two spindles is currently attached as /dev/ad0.
Partition Ordering Modern disk drives operate with fairly uniform areal density across the surface of the disk. That implies that more data is available under the heads without seeking on the outer cylinders than on the inner cylinders. We will allocate partitions most critical to system performance from these outer cylinders as /stand/sysinstall generally does. - The root file system is traditionally the outermost, even though + The root filesystem is traditionally the outermost, even though it generally is not as critical to system performance as others. (However root can have a larger impact on performance if it contains /tmp and /var as it does in this example.) The FreeBSD boot loaders assume that the - root file system lives in the a partition. + root filesystem lives in the a partition. There is no requirement that the a partition start on the outermost cylinders, but this convention makes it easier to manage disk labels. Swap performance is critical so it comes next on our way toward the center. I/O operations here tend to be large and contiguous. Having as much data under the heads as possible avoids seeking while swapping. With all the smaller partitions out of the way, we finish up the disk with /home and /usr. Access patterns here tend not to be as intense as for other - file systems (especially if there is an abundant supply of RAM + filesystems (especially if there is an abundant supply of RAM and read cache hit rates are high). If the pair of spindles you have are large enough to allow for more than /home and /usr, - it is fine to plan for additional file systems here. + it is fine to plan for additional filesystems here.
Assigning Partitions to Spindles We will want to assign partitions to these spindles so that either can fail - without loss of data on file systems configured for + without loss of data on filesystems configured for resilience. Reliability on /usr and /home is best achieved using Vinum mirroring. Resilience will have to come differently, however, for the root - file system since Vinum + filesystem since Vinum is not a part of the FreeBSD boot sequence. Here we will have to settle for two identical partitions with a periodic copy from the primary to the backup secondary. The kernel already has support for interleaved swap across all available partitions so there is no need for help from Vinum here. /stand/sysinstall will automatically configure /etc/fstab for all swap partitions given. The &vinum.ap; bootstrapping method given below requires a pair of spindles that I will call the root spindle and the rootback spindle. The rootback spindle must be the same size or larger than the root spindle. These instructions first allocate all space on the root spindle and then allocate exactly that amount of space on a rootback spindle. (After &vinum.ap; is bootstrapped, there is nothing special about either of these spindles--they are interchangeable.) You can later use the remaining space on the rootback spindle for - other file systems. + other filesystems. If you have more than two spindles, the bootvinum Perl script and the procedure below will help you initialize them for use with &vinum.ap;. However you will have to figure out how to assign partitions to them on your own.
Assigning Space to Partitions For this example, I will use two spindles: one with 4,124,673 blocks (about 2 GB) on /dev/ad0 and one with 8,420,769 blocks (about 4 GB) on /dev/ad2. It is best to configure your two spindles on separate controllers so that both can operate in parallel and so that you will have failure resilience in case a controller dies. Note that mirrored volume write performance will be halved in cases where both spindles share a controller that requires they operate serially (as is often the case with ATA controllers). One spindle will be the master on the primary ATA controller and the other will be the master on the secondary ATA controller. Recall that we will be allocating space on the smaller spindle first and the larger spindle second.
Assigning Partitions on the Root Spindle We will allocate 200,000 blocks (about 93 MB) - for a root file system on each spindle + for a root filesystem on each spindle (/dev/ad0s1a and /dev/ad2s1a). We will initially allocate 200,265 blocks for a swap partition on each spindle, giving a total of about 186 MB of swap space (/dev/ad0s1b and /dev/ad2s1b). We will lose 265 blocks from each swap partition as part of the bootstrapping process. This is the size of the space used by Vinum to store configuration information. The space will be taken from swap and given to a vinum partition but will be unavailable for Vinum subdisks. I have done the partition allocation in nice round numbers of blocks just to emphasize where the 265 blocks go. There is nothing wrong with allocating space in MB if that is more convenient for you. This leaves 4,124,673 - 200,000 - 200,265 = 3,724,408 blocks (about 1,818 MB) on the root spindle for Vinum partitions (/dev/ad0s1e and /dev/ad2s1f). From this, allocate the 265 blocks for Vinum configuration information, 1,000,000 blocks (about 488 MB) for /home, and the remaining 2,724,408 blocks (about 1,330 MB) for /usr. See below to see this graphically. The left-hand side of below shows what spindle ad0 will look like at the end of phase 2. The right-hand side shows what it will look like at the end of phase 3.
Spindle ad0 Before and After Vinum ad0 Before Vinum Offset (blocks) ad0 After Vinum +----------------------+ <-- 0--> +----------------------+ | root | | root | | /dev/ad0s1a | | /dev/ad0s1a | +----------------------+ <-- 200000--> +----------------------+ | swap | | swap | | /dev/ad0s1b | | /dev/ad0s1b | | | 400000--> +----------------------+ | | | Vinum drive YouCrazy | | | | /dev/ad0s1h | +----------------------+ <-- 400265--> +-----------------+ | | /home | | Vinum sd | | | /dev/ad0s1e | | home.p0.s0 | | +----------------------+ <--1400265--> +-----------------+ | | /usr | | Vinum sd | | | /dev/ad0s1f | | usr.p0.s0 | | +----------------------+ <--4124673--> +-----------------+----+ Not to scale Spindle /dev/ad0 Before and After Vinum
Assigning Partitions on the Rootback Spindle The /rootback and swap partition sizes on the rootback spindle must match the root and swap partition sizes on the root spindle. That leaves 8,420,769 - 200,000 - 200,265 = 8,020,504 blocks for the Vinum partition. Mirrors of /home and /usr receive the same allocation as on the root spindle. That will leave an extra 2 GB or so that we can deal with later. See below to see this graphically. The left-hand side of below shows what spindle ad2 will look like at the beginning of phase 4. The right-hand side shows what it will look like at the end.
Spindle ad2 Before and After Vinum ad2 Before Vinum Offset (blocks) ad2 After Vinum +----------------------+ <-- 0--> +----------------------+ | /rootback | | /rootback | | /dev/ad2s1e | | /dev/ad2s1a | +----------------------+ <-- 200000--> +----------------------+ | swap | | swap | | /dev/ad2s1b | | /dev/ad2s1b | | | 400000--> +----------------------+ | | | Vinum drive UpWindow | | | | /dev/ad2s1h | +----------------------+ <-- 400265--> +-----------------+ | | /NOFUTURE | | Vinum sd | | | /dev/ad2s1f | | home.p1.s0 | | | | 1400265--> +-----------------+ | | | | Vinum sd | | | | | usr.p1.s0 | | | | 4124673--> +-----------------+ | | | | Vinum sd | | | | | hope.p0.s0 | | +----------------------+ <--8420769--> +-----------------+----+ Not to scale Spindle ad2 Before and After Vinum
Preparation of Tools The bootvinum Perl script given below in will make the Vinum bootstrapping process much easier if you can run it on the machine being bootstrapped. It is over 200 lines and you would not want to type it in. At this point, I recommend that you copy it to a floppy or arrange some alternative method of making it readily available so that it can be available later when needed. For example: &prompt.root; fdformat -f 1440 /dev/fd0 &prompt.root; newfs_msdos -f 1440 /dev/fd0 &prompt.root; mount_msdos /dev/fd0 /mnt &prompt.root; cp /usr/share/examples/vinum/bootvinum /mnt XXX Someday, I would like this script to live in /usr/share/examples/vinum. Till then, please use this link to get a copy.
Bootstrapping Phase 2: Minimal OS Installation Our goal in this phase is to complete the smallest possible FreeBSD installation in such a way that we can later install Vinum. We will use only partitions of type 4.2BSD (i.e., regular UFS file systems) since that is the only type supported by /stand/sysinstall.
Phase 2 Example Start up the FreeBSD installation process by running /stand/sysinstall from installation media as you normally would. Fdisk partition all spindles as needed. Make sure to select BootMgr for all spindles. Partition the root spindle with appropriate block allocations as described above in . For this example on a 2 GB spindle, I will use 200,000 blocks for root, 200,265 blocks for swap, 1,000,000 blocks for /home, and the rest of the spindle (2,724,408 blocks) for /usr. (/stand/sysinstall should automatically assign these to /dev/ad0s1a, /dev/ad0s1b, /dev/ad0s1e, and /dev/ad0s1f by default.) If you prefer soft updates as I do and you are using 4.4-RELEASE or better, this is a good time to enable them. Partition the rootback spindle with the appropriate block allocations as described above in . For this example on a 4 GB spindle, I will use 200,000 blocks for /rootback, 200,265 blocks for swap, and the rest of the spindle (8,020,504 blocks) for /NOFUTURE. (/stand/sysinstall should automatically assign these to /dev/ad2s1e, /dev/ad2s1b, and /dev/ad2s1f by default.) We do not really want to have a - /NOFUTURE UFS file system (we + /NOFUTURE UFS filesystem (we want a vinum partition instead), but that is the best choice we have for the space given the limitations of /stand/sysinstall. Mount point names beginning with NOFUTURE and rootback serve as sentinels to the bootstrapping script presented in below. Partition any other spindles with swap if desired and a - single /NOFUTURExx file system. + single /NOFUTURExx filesystem. Select a minimum system install for now even if you want to end up with more distributions loaded later. Do not worry about system configuration options at this point--get Vinum set up and get the partitions in the right places first. Exit /stand/sysinstall and reboot. Do a quick test to verify that the minimum installation was successful. The left-hand side of above and the left-hand side of above show how the disks will look at this point.
Bootstrapping Phase 3: Root Spindle Setup Our goal in this phase is get Vinum set up and running on the root spindle. We will embed the existing /usr and - /home file systems in a + /home filesystems in a Vinum partition. Note that the Vinum volumes created will not yet be failure-resilient since we have only one underlying Vinum drive to hold them. The resulting system will automatically start Vinum as it boots to multi-user mode.
Phase 3 Example Login as root. - We will need a directory in the root file system in + We will need a directory in the root filesystem in which to keep a few files that will be used in the Vinum bootstrapping process. &prompt.root; mkdir /bootvinum &prompt.root; cd /bootvinum Several files need to be prepared for use in bootstrapping. I have written a Perl script that makes all the required files for you. Copy this script to /bootvinum by floppy disk, tape, network, or any convenient means and then run it. (If you cannot get this script copied onto the machine being bootstrapped, then see below for a manual alternative.) &prompt.root; cp /mnt/bootvinum . &prompt.root; ./bootvinum bootvinum produces no output when run successfully. If you get any errors, something may have gone wrong when you were creating partitions with /stand/sysinstall above. Running bootvinum will: Create /etc/fstab.vinum based on what it finds in your existing /etc/fstab Create new disk labels for each spindle mentioned in /etc/fstab and keep copies of the current disk labels Create files needed as input to vinum for building Vinum objects on each spindle Create many alternates to /etc/fstab.vinum that might come in handy should a spindle fail You may want to take a look at these files to learn more about the disk partitioning required for Vinum or to learn more about the commands needed to create Vinum objects. We now need to install new spindle partitioning for /dev/ad0. This requires that /dev/ad0s1b not be in use for swapping so we have to reboot in single-user mode. First, reboot the system. &prompt.root; reboot Next, enter single-user mode. Hit [Enter] to boot immediately, or any other key for command prompt. Booting [kernel] in 8 seconds... Type '?' for a list of commands, 'help' for more detailed help. ok boot -s In single-user mode, install the new partitioning created above. &prompt.root; cd /bootvinum &prompt.root; disklabel -R ad0s1 disklabel.ad0s1 &prompt.root; disklabel -R ad2s1 disklabel.ad2s1 If you have additional spindles, repeat the above commands as appropriate for them. We are about to start Vinum for the first time. It is going to want to create several device nodes under /dev/vinum so we will need to mount the - root file system for read/write access. + root filesystem for read/write access. &prompt.root; fsck -p / &prompt.root; mount / Now it is time to create the Vinum objects that - will embed the existing non-root file systems on + will embed the existing non-root filesystems on the root spindle in a Vinum partition. This will load the Vinum kernel module and start Vinum as a side effect. &prompt.root; vinum create create.YouCrazy You should see a list of Vinum objects created that looks like the following: 1 drives: D YouCrazy State: up Device /dev/ad0s1h Avail: 0/1818 MB (0%) 2 volumes: V home State: up Plexes: 1 Size: 488 MB V usr State: up Plexes: 1 Size: 1330 MB 2 plexes: P home.p0 C State: up Subdisks: 1 Size: 488 MB P usr.p0 C State: up Subdisks: 1 Size: 1330 MB 2 subdisks: S home.p0.s0 State: up PO: 0 B Size: 488 MB S usr.p0.s0 State: up PO: 0 B Size: 1330 MB You should also see several kernel messages which state that the Vinum objects you have created are now up. - Our non-root file systems should now be embedded in a + Our non-root filesystems should now be embedded in a Vinum partition and hence available through Vinum volumes. It is important to test that this embedding worked. &prompt.root; fsck -n /dev/vinum/home &prompt.root; fsck -n /dev/vinum/usr This should produce no errors. If it does produce errors do not fix them. Instead, go back and examine the root spindle partition tables before and after Vinum to see if you can spot the error. You can back out the partition table changes by using disklabel -R with the disklabel.*.b4vinum files. - While we have the root file system mounted read/write, this is + While we have the root filesystem mounted read/write, this is a good time to install /etc/fstab. &prompt.root; mv /etc/fstab /etc/fstab.b4vinum &prompt.root; cp /etc/fstab.vinum /etc/fstab We are now done with tasks requiring single-user mode, so it is safe to go multi-user from here on. &prompt.root; ^D Login as root. Edit /etc/rc.conf and add this line: start_vinum="YES"
Bootstrapping Phase 4: Rootback Spindle Setup Our goal in this phase is to get redundant copies of all data from the root spindle to the rootback spindle. We will first create the necessary Vinum objects on the rootback spindle. Then we will ask Vinum to copy the data from the root spindle to the rootback spindle. Finally, we use dump and restore - to copy the root file system. + to copy the root filesystem.
Phase 4 Example Now that Vinum is running on the root spindle, we can bring it up on the rootback spindle so that our Vinum volumes can become failure-resilient. &prompt.root; cd /bootvinum &prompt.root; vinum create create.UpWindow You should see a list of Vinum objects created that looks like the following: 2 drives: D YouCrazy State: up Device /dev/ad0s1h Avail: 0/1818 MB (0%) D UpWindow State: up Device /dev/ad2s1h Avail: 2096/3915 MB (53%) 2 volumes: V home State: up Plexes: 2 Size: 488 MB V usr State: up Plexes: 2 Size: 1330 MB 4 plexes: P home.p0 C State: up Subdisks: 1 Size: 488 MB P usr.p0 C State: up Subdisks: 1 Size: 1330 MB P home.p1 C State: faulty Subdisks: 1 Size: 488 MB P usr.p1 C State: faulty Subdisks: 1 Size: 1330 MB 4 subdisks: S home.p0.s0 State: up PO: 0 B Size: 488 MB S usr.p0.s0 State: up PO: 0 B Size: 1330 MB S home.p1.s0 State: stale PO: 0 B Size: 488 MB S usr.p1.s0 State: stale PO: 0 B Size: 1330 MB You should also see several kernel messages which state that some of the Vinum objects you have created are now up while others are faulty or stale. Now we ask Vinum to copy each of the subdisks on drive YouCrazy to drive UpWindow. This will change the state of the newly created Vinum subdisks from stale to up. It will also change the state of the newly created Vinum plexes from faulty to up. First, we do the new subdisk we added to /home. &prompt.root; vinum start -w home.p1.s0 reviving home.p1.s0 (time passes . . . ) home.p1.s0 is up by force home.p1 is up home.p1.s0 is up My 5,400 RPM EIDE spindles copied at about 3.5 MBytes/sec. Your mileage may vary. Next we do the new subdisk we added to /usr. &prompt.root; vinum -w start usr.p1.s0 reviving usr.p1.s0 (time passes . . . ) usr.p1.s0 is up by force usr.p1 is up usr.p1.s0 is up All Vinum objects should be in state up at this point. The output of vinum list should look like the following: 2 drives: D YouCrazy State: up Device /dev/ad0s1h Avail: 0/1818 MB (0%) D UpWindow State: up Device /dev/ad2s1h Avail: 2096/3915 MB (53%) 2 volumes: V home State: up Plexes: 2 Size: 488 MB V usr State: up Plexes: 2 Size: 1330 MB 4 plexes: P home.p0 C State: up Subdisks: 1 Size: 488 MB P usr.p0 C State: up Subdisks: 1 Size: 1330 MB P home.p1 C State: up Subdisks: 1 Size: 488 MB P usr.p1 C State: up Subdisks: 1 Size: 1330 MB 4 subdisks: S home.p0.s0 State: up PO: 0 B Size: 488 MB S usr.p0.s0 State: up PO: 0 B Size: 1330 MB S home.p1.s0 State: up PO: 0 B Size: 488 MB S usr.p1.s0 State: up PO: 0 B Size: 1330 MB - Copy the root file system so that you will have a backup. + Copy the root filesystem so that you will have a backup. &prompt.root; cd /rootback &prompt.root; dump 0f - / | restore rf - &prompt.root; rm restoresymtable &prompt.root; cd / You may see errors like this: ./tmp/rstdir1001216411: (inode 558) not found on tape cannot find directory inode 265 abort? [yn] n expected next file 492, got 491 They seem to cause no harm. - I suspect they are a consequence of dumping the file system + I suspect they are a consequence of dumping the filesystem containing /tmp and/or the pipe connecting dump and restore. Make a directory on which we can mount a damaged root - file system during the recovery process. + filesystem during the recovery process. &prompt.root; mkdir /rootbad Remove sentinel mount points that are now unused. &prompt.root; rmdir /NOFUTURE* Create empty &vinum.ap; drives on remaining spindles. &prompt.root; vinum create create.ThruBank &prompt.root; ... At this point, the reliable server foundation is complete. The right-hand side of above and the right-hand side of above show how the disks will look. You may want to do a quick reboot to multi-user and give it a quick test drive. This is also a good point to complete installation of other distributions beyond the minimal install. Add packages, ports, and users as required. Configure /etc/rc.conf as required. After you have completed your server configuration, remember to do one more copy of root to /rootback as shown above before placing the server into production. Make a schedule to refresh /rootback periodically. It may be a good idea to mount /rootback read-only for normal operation of the server. This does, however, complicate the periodic refresh a bit. Do not forget to watch /var/log/messages carefully for errors. Vinum may automatically avoid failed hardware in a way that users do not notice. You must watch for such failures and get them repaired before a second failure results in data loss. You may see Vinum noting damaged objects at server boot time.
Where to Go from Here? Now that you have established the foundation of a reliable server, there are several things you might want to try next.
Make a Vinum Volume with Remaining Space Following are the steps to create another Vinum volume with space remaining on the rootback spindle. This volume will not be resilient to spindle failure since it has only one plex on a single spindle. Create a file with the following contents: volume hope plex name hope.p0 org concat volume hope sd name hope.p0.s0 drive UpWindow plex hope.p0 len 0 Specifying a length of 0 for the hope.p0.s0 subdisk asks Vinum to use whatever space is left available on the underlying drive. Feed these commands into vinum . &prompt.root; vinum create filename Now we newfs the volume and mount it. &prompt.root; newfs -v /dev/vinum/hope &prompt.root; mkdir /hope &prompt.root; mount /dev/vinum/hope /hope Edit /etc/fstab if you want /hope mounted at boot time.
Try Out More Vinum Commands You might already be familiar with vinum to get a list of all Vinum objects. Try following it to see more detail. If you have more spindles and you want to bring them up as concatenated, mirrored, or striped volumes, then give vinum drivelist, vinum drivelist, or vinum drivelist a try. See &man.vinum.8; for sample configurations and important performance considerations before settling on a final organization for your additional spindles. The failure recovery instructions below will also give you some experience using more Vinum commands.
Failure Scenarios This section contains descriptions of various failure scenarios. For each scenario, there is a subsection on how to configure your server for degraded mode operation, how to recover from the failure, how to exit degraded mode, and how to simulate the failure. Make a hard copy of these instructions and leave them inside the CPU case, being careful not to interfere with ventilation.
- Root file system on ad0 unusable, rest of drive ok + Root filesystem on ad0 unusable, rest of drive ok We assume here that the boot blocks and disk label on /dev/ad0 are ok. If your BIOS can boot from a drive other than C:, you may be able to get around this limitation.
Configure Server for Degraded Mode Use BootMgr to load kernel from /dev/ad2s1a. Hit F5 in BootMgr to select Drive 1. Hit F1 to select FreeBSD. After the kernel is loaded, hit any key but enter to interrupt the boot sequence. Boot into single-user mode and allow explicit entry of - a root file system. + a root filesystem. Hit [Enter] to boot immediately, or any other key for command prompt. Booting [kernel] in 8 seconds... Type '?' for a list of commands, 'help' for more detailed help. ok boot -as Select /rootback - as your root file system. + as your root filesystem. - Manual root file system specification: + Manual root filesystem specification: <fstype>:<device> Mount <device> using filesystem <fstype> e.g. ufs:/dev/da0s1a ? List valid disk boot devices <empty line> Abort manual input mountroot> ufs:/dev/ad2s1a Now that you are in single-user mode, change /etc/fstab to avoid the - bad root file system. + bad root filesystem. If you used the bootvinum Perl script from below, then these commands should configure your server for degraded mode. &prompt.root; fsck -p / &prompt.root; mount / &prompt.root; cd /etc &prompt.root; mv fstab fstab.bak &prompt.root; cp fstab_ad0s1_root_bad fstab &prompt.root; cd / &prompt.root; mount -o ro / &prompt.root; vinum start &prompt.root; fsck -p &prompt.root; ^D
Recovery Restore /dev/ad0s1a from backups or copy /rootback to it with these commands: &prompt.root; umount /rootbad &prompt.root; newfs /dev/ad0s1a &prompt.root; tunefs -n enable /dev/ad0s1a &prompt.root; mount /rootbad &prompt.root; cd /rootbad &prompt.root; dump 0f - / | restore rf - &prompt.root; rm restoresymtable
Exiting Degraded Mode Enter single-user mode. &prompt.root; shutdown now Put /etc/fstab back to normal and reboot. &prompt.root; cd /rootbad/etc &prompt.root; rm fstab &prompt.root; mv fstab.bak fstab &prompt.root; reboot Reboot and hit F1 to boot from /dev/ad0 when prompted by BootMgr.
Simulation This kind of failure can be simulated by shutting down to single-user mode and then booting as shown above in .
Drive ad2 Fails This section deals with the total failure of /dev/ad2.
Configure Server for Degraded Mode After the kernel is loaded, hit any key but Enter to interrupt the boot sequence. Boot into single-user mode. Hit [Enter] to boot immediately, or any other key for command prompt. Booting [kernel] in 8 seconds... Type '?' for a list of commands, 'help' for more detailed help. ok boot -s Change /etc/fstab to avoid the bad drive. If you used the bootvinum Perl script from below, then these commands should configure your server for degraded mode. &prompt.root; fsck -p / &prompt.root; mount / &prompt.root; cd /etc &prompt.root; mv fstab fstab.bak &prompt.root; cp fstab_only_have_ad0s1 fstab &prompt.root; cd / &prompt.root; mount -o ro / &prompt.root; vinum start &prompt.root; fsck -p &prompt.root; ^D If you do not have modified versions of /etc/fstab that are ready for use, then you can use ed to make one. Alternatively, you can fsck and mount /usr and then use your favorite editor.
Recovery We assume here that your server is up and running multi-user in degraded mode on just /dev/ad0 and that you have a new spindle now on /dev/ad2 ready to go. You will need a new spindle with enough room to hold root and swap partitions plus a Vinum partition large enough to hold /home and /usr. Create a BIOS partition (slice) on the new spindle. &prompt.root; /stand/sysinstall Select Custom. Select Partition. Select ad2. Create a FreeBSD (type 165) slice large enough to hold everything mentioned above. Write changes. Yes, you are absolutely sure. Select BootMgr. Quit Partitioning. Exit /stand/sysinstall. Create disk label partitioning based on current /dev/ad0 partitioning. &prompt.root; disklabel ad0 > /tmp/ad0 &prompt.root; disklabel -e ad2 This will drop you into your favorite editor. Copy the lines for the a and b partitions from /tmp/ad0 to the ad2 disklabel. Add the size of the a and b partitions to find the proper offset for the h partition. Subtract this offset from the size of the c partition to find the proper size for the h partition. Define an h partition with the size and offset calculated above. Set the fstype column to vinum. Save the file and quit your editor. Tell Vinum about the new drive. Ask Vinum to start an editor with a copy of the current configuration. &prompt.root; vinum create Uncomment the drive line referring to drive UpWindow and set device to /dev/ad2s1h. Save the file and quit your editor. Now that Vinum has two spindles again, revive the mirrors. &prompt.root; vinum start -w usr.p1.s0 &prompt.root; vinum start -w home.p1.s0 Now we need to restore /rootback to a current copy of the - root file system. + root filesystem. These commands will accomplish this. &prompt.root; newfs /dev/ad2s1a &prompt.root; tunefs -n enable /dev/ad2s1a &prompt.root; mount /dev/ad2s1a /mnt &prompt.root; cd /mnt &prompt.root; dump 0f - / | restore rf - &prompt.root; rm restoresymtable &prompt.root; cd / &prompt.root; umount /mnt
Exiting Degraded Mode Enter single-user mode. &prompt.root; shutdown now Return /etc/fstab to its normal state and reboot. &prompt.root; cd /etc &prompt.root; rm fstab &prompt.root; mv fstab.bak fstab &prompt.root; reboot
Simulation You can simulate this kind of failure by unplugging /dev/ad2, write-protecting it, or by this procedure: Shutdown to single-user mode. - Unmount all non-root file systems. + Unmount all non-root filesystems. Clobber any existing Vinum configuration and partitioning on /dev/ad2. &prompt.root; vinum stop &prompt.root; dd if=/dev/zero of=/dev/ad2s1h count=512 &prompt.root; dd if=/dev/zero of=/dev/ad2 count=512
Drive ad0 Fails Some BIOSes can boot from drive 1 or drive 2 (often called C: or D:), while others can boot only from drive 1. If your BIOS can boot from either, the fastest road to recovery might be to boot directly from /dev/ad2 in single-user mode and install /etc/fsatb_only_have_ad2s1 as /etc/fstab. You would then have to adapt the /dev/ad2 failure recovery instructions from above. If your BIOS can only boot from drive one, then you will have to unplug drive YouCrazy from the controller for /dev/ad2 and plug it into the controller for /dev/ad0. Then continue with the instructions for /dev/ad2 failure recovery in above.
bootvinum Perl Script The bootvinum Perl script below reads /etc/fstab and current drive partitioning. It then writes several files in the current directory and several variants of /etc/fstab in /etc. These files significantly simplify the installation of Vinum and recovery from spindle failures. #!/usr/bin/perl -w use strict; use FileHandle; -my $config_tag1 = '$Id: article.sgml,v 1.6 2002-02-28 02:55:01 keramida Exp $'; +my $config_tag1 = '$Id: article.sgml,v 1.7 2002-05-16 01:42:03 trhodes Exp $'; # Copyright (C) 2001 Robert A. Van Valzah # # Bootstrap Vinum # # Read /etc/fstab and current partitioning for all spindles mentioned there. -# Generate files needed to mirror all file systems on root spindle. +# Generate files needed to mirror all filesystems on root spindle. # A new partition table for each spindle # Input for the vinum create command to create Vinum objects on each spindle # A copy of fstab mounting Vinum volumes instead of BSD partitions # Copies of fstab altered for server's degraded modes of operation # See handbook for instructions on how to use the the files generated. # N.B. This bootstrapping method shrinks size of swap partition by the size # of Vinum's on-disk configuration (265 sectors). It embeds existing file # systems on the root spindle in Vinum objects without having to copy them. # Thanks to Greg Lehey for suggesting this bootstrapping method. # Expectations: # The root spindle must contain at least root, swap, and /usr partitions # The rootback spindle must have matching /rootback and swap partitions -# Other spindles should only have a /NOFUTURE* file system and maybe swap +# Other spindles should only have a /NOFUTURE* filesystem and maybe swap # File systems named /NOFUTURE* will be replaced with Vinum drives # Change configuration variables below to suit your taste my $vip = 'h'; # VInum Partition my @drv = ('YouCrazy', 'UpWindow', 'ThruBank', # Vinum DRiVe names 'OutSnakes', 'MeWild', 'InMovie', 'HomeJames', 'DownPrices', 'WhileBlind'); # No configuration variables beyond this point my %vols; # One entry per Vinum volume to be created my @spndl; # One entry per SPiNDLe my $rsp; # Root SPindle (as in /dev/$rsp) my $rbsp; # RootBack SPindle (as in /dev/$rbsp) my $cfgsiz = 265; # Size of Vinum on-disk configuration info in sectors -my $nxtpas = 2; # Next fsck pass number for non-root file systems +my $nxtpas = 2; # Next fsck pass number for non-root filesystems # Parse fstab, generating the version we'll need for Vinum and noting # spindles in use. my $fsin = "/etc/fstab"; #my $fsin = "simu/fstab"; open(FSIN, "$fsin") || die("Couldn't open $fsin: $!\n"); my $fsout = "/etc/fstab.vinum"; open(FSOUT, ">$fsout") || die("Couldn't open $fsout for writing: $!\n"); while (<FSIN>) { my ($dev, $mnt, $fstyp, $opt, $dump, $pass) = split; next if $dev =~ /^#/; if ($mnt eq '/' || $mnt eq '/rootback' || $mnt =~ /^\/NOFUTURE/) { my $dn = substr($dev, 5, length($dev)-6); # Device Name without /dev/ push(@spndl, $dn) unless grep($_ eq $dn, @spndl); $rsp = $dn if $mnt eq '/'; next if $mnt =~ /^\/NOFUTURE/; } # Move /rootback from partition e to a if ($mnt =~ /^\/rootback/) { $dev =~ s/e$/a/; $pass = 1; $rbsp = substr($dev, 5, length($dev)-6); print FSOUT "$dev\t\t$mnt\t$fstyp\t$opt\t\t$dump\t$pass\n"; next; } - # Move non-root file systems on smallest spindle into Vinum + # Move non-root filesystems on smallest spindle into Vinum if (defined($rsp) && $dev =~ /^\/dev\/$rsp/ && $dev =~ /[d-h]$/) { $pass = $nxtpas++; print FSOUT "/dev/vinum$mnt\t\t$mnt\t\t$fstyp\t$opt\t\t$dump\t$pass\n"; $vols{$dev}->{mnt} = substr($mnt, 1); next; } print FSOUT $_; } close(FSOUT); die("Found more spindles than we have abstract names\n") if $#spndl > $#drv; die("Didn't find a root partition!\n") if !defined($rsp); die("Didn't find a /rootback partition!\n") if !defined($rbsp); # Table of server's Degraded Modes # One row per mode with hash keys # fn FileName # xpr eXPRession needed to convert fstab lines for this mode # cm1 CoMment 1 describing this mode # cm2 CoMment 2 describing this mode # FH FileHandle (dynamically initialized below) my @DM = ( { cm1 => "When we only have $rsp, comment out lines using $rbsp", fn => "/etc/fstab_only_have_$rsp", xpr => "s:^/dev/$rbsp:#\$&:", }, { cm1 => "When we only have $rbsp, comment out lines using $rsp and", cm2 => "rootback becomes root", fn => "/etc/fstab_only_have_$rbsp", xpr => "s:^/dev/$rsp:#\$&: || s:/rootback:/\t:", }, { cm1 => "When only $rsp root is bad, /rootback becomes root and", cm2 => "root becomes /rootbad", fn => "/etc/fstab_${rsp}_root_bad", xpr => "s:\t/\t:\t/rootbad: || s:/rootback:/\t:", }, ); # Initialize output FileHandles and write comments foreach my $dm (@DM) { my $fh = new FileHandle; $fh->open(">$dm->{fn}") || die("Can't write $dm->{fn}: $!\n"); print $fh "# $dm->{cm1}\n" if $dm->{cm1}; print $fh "# $dm->{cm2}\n" if $dm->{cm2}; $dm->{FH} = $fh; } # Parse the Vinum version of fstab written above and write versions needed # for server's degraded modes. open(FSOUT, "$fsout") || die("Couldn't open $fsout: $!\n"); while (<FSOUT>) { my $line = $_; foreach my $dm (@DM) { $_ = $line; eval $dm->{xpr}; print {$dm->{FH}} $_; } } # Parse partition table for each spindle and write versions needed for Vinum my $rootsiz; # ROOT partition SIZe my $swapsiz; # SWAP partition SIZe my $rspminoff; # Root SPindle MINimum OFFset of non-root, non-swap, non-c parts my $rspsiz; # Root SPindle SIZe my $rbspsiz; # RootBack SPindle SIZe foreach my $i (0..$#spndl) { my $dlin = "disklabel $spndl[$i] |"; # my $dlin = "simu/disklabel.$spndl[$i]"; open(DLIN, "$dlin") || die("Couldn't open $dlin: $!\n"); my $dlout = "disklabel.$spndl[$i]"; open(DLOUT, ">$dlout") || die("Couldn't open $dlout for writing: $!\n"); my $dlb4 = "$dlout.b4vinum"; open(DLB4, ">$dlb4") || die("Couldn't open $dlb4 for writing: $!\n"); my $minoff; # MINimum OFFset of non-root, non-swap, non-c partitions my $totsiz = 0; # TOTal SIZe of all non-root, non-swap, non-c partitions my $swapspndl = 0; # True if SWAP partition on this SPiNDLe while (<DLIN>) { print DLB4 $_; my ($part, $siz, $off, $fstyp, $fsiz, $bsiz, $bps) = split; if ($part && $part eq 'a:' && $spndl[$i] eq $rsp) { $rootsiz = $siz; } if ($part && $part eq 'e:' && $spndl[$i] eq $rbsp) { if ($rootsiz != $siz) { die("Rootback size ($siz) != root size ($rootsiz)\n"); } } if ($part && $part eq 'c:') { $rspsiz = $siz if $spndl[$i] eq $rsp; $rbspsiz = $siz if $spndl[$i] eq $rbsp; } # Make swap partition $cfgsiz sectors smaller if ($part && $part eq 'b:') { if ($spndl[$i] eq $rsp) { $swapsiz = $siz; } else { if ($swapsiz != $siz) { die("Swap partition sizes unequal across spindles\n"); } } printf DLOUT "%4s%9d%9d%10s\n", $part, $siz-$cfgsiz, $off, $fstyp; $swapspndl = 1; next; } # Move rootback spindle e partitions to a if ($part && $part eq 'e:' && $spndl[$i] eq $rbsp) { printf DLOUT "%4s%9d%9d%10s%9d%6d%6d\n", 'a:', $siz, $off, $fstyp, $fsiz, $bsiz, $bps; next; } # Delete non-root, non-swap, non-c partitions but note their minimum # offset and total size that're needed below. if ($part && $part =~ /^[d-h]:$/) { $minoff = $off unless $minoff; $minoff = $off if $off < $minoff; $totsiz += $siz; if ($spndl[$i] eq $rsp) { # If doing spindle containing root my $dev = "/dev/$spndl[$i]" . substr($part, 0, 1); $vols{$dev}->{siz} = $siz; $vols{$dev}->{off} = $off; $rspminoff = $minoff; } next; } print DLOUT $_; } if ($swapspndl) { # If there was a swap partition on this spindle # Make a Vinum partition the size of all non-root, non-swap, # non-c partitions + the size of Vinum's on-disk configuration. # Set its offset so that the start of the first subdisk it contains - # coincides with the first file system we're embedding in Vinum. + # coincides with the first filesystem we're embedding in Vinum. printf DLOUT "%4s%9d%9d%10s\n", "$vip:", $totsiz+$cfgsiz, $minoff-$cfgsiz, 'vinum'; } else { # No need to mess with size size and offset if there was no swap printf DLOUT "%4s%9d%9d%10s\n", "$vip:", $totsiz, $minoff, 'vinum'; } } die("Swap partition not found\n") unless $swapsiz; die("Swap partition not larger than $cfgsiz blocks\n") unless $swapsiz>$cfgsiz; die("Rootback spindle size not >= root spindle size\n") unless $rbspsiz>=$rspsiz; # Generate input to vinum create command needed for each spindle. foreach my $i (0..$#spndl) { my $cfn = "create.$drv[$i]"; # Create File Name open(CF, ">$cfn") || die("Can't open $cfn for writing: $!\n"); print CF "drive $drv[$i] device /dev/$spndl[$i]$vip\n"; next unless $spndl[$i] eq $rsp || $spndl[$i] eq $rbsp; foreach my $dev (keys(%vols)) { my $mnt = $vols{$dev}->{mnt}; my $siz = $vols{$dev}->{siz}; my $off = $vols{$dev}->{off}-$rspminoff+$cfgsiz; print CF "volume $mnt\n" if $spndl[$i] eq $rsp; print CF <<EOF; plex name $mnt.p$i org concat volume $mnt sd name $mnt.p$i.s0 drive $drv[$i] plex $mnt.p$i len ${siz}s driveoffset ${off}s EOF } } Manual Vinum Bootstrapping The bootvinum Perl script in makes life easier, but it may be necessary to manually perform some or all of the steps that it automates. This appendix describes how you would manually mimic the script. Make a copy of /etc/fstab to be customized. &prompt.root; cp /etc/fstab /etc/fstab.vinum Edit /etc/fstab.vinum. Change the device column of non-root partitions on the root spindle to /dev/vinum/mnt. Change the pass column of non-root partitions on the root spindle to 2, 3, etc. Delete any lines with mountpoint matching /NOFUTURE*. Change the device column of /rootback from e to a. Change the pass column of /rootback to 1. Prepare disklabels for editing: &prompt.root; cd /bootvinum &prompt.root; disklabel ad0s1 > disklabel.ad0s1 &prompt.root; cp disklabel.ad0s1 disklabel.ad0s1.b4vinum &prompt.root; disklabel ad2s1 > disklabel.ad2s1 &prompt.root; cp disklabel.ad2s1 disklabel.ad2s1.b4vinum Edit /etc/disklabel.ad?s1. On the root spindle: Decrease the size of the b partition by 265 blocks. Note the size and offset of the a and b partitions. Note the smallest offset for partitions d-h. Note the size and offset for all non-root, non-swap partitions (/home was probably on e and /usr was probably on f). Delete partitions d-h. Create a new h partition with offset 265 blocks less than the smallest offset for partitions d-h noted above. Set its size to the size of the c partition less the smallest offset for partitions d-h noted above + 265 blocks. Vinum can use any partition other than c. It is not strictly necessary to use h for all your Vinum partitions, but it is good practice to be consistent across all spindles. Set the fstype of this new partition to vinum. On the rootback spindle: Move the e partition to a. Verify that the size of the a and b partitions matches the root spindle. Note the smallest offset for partitions d-h. Delete partitions d-h. Create a new h partition with offset 265 blocks less than the smallest offset noted above for partitions d-h. Set its size to the size of the c partition less the smallest offset for partitions d-h noted above + 265 blocks. Set the fstype of this new partition to vinum. Create a file named create.YouCrazy that contains: drive YouCrazy device /dev/ad0s1h volume home plex name home.p0 org concat volume home sd name home.p0.s0 drive YouCrazy plex home.p0 len $hl driveoffset $ho volume usr plex name usr.p0 org concat volume usr sd name usr.p0.s0 drive YouCrazy plex usr.p0 len $ul driveoffset $uo Where: $hl is the length noted above for /home. $ho is the offset noted above for /home less the smallest offset noted above + 265 blocks. $ul is the length noted above for /usr. $uo is the offset noted above for /usr less the smallest offset noted above + 265 blocks. Create a file named create.UpWindow containing: drive UpWindow device /dev/ad2s1h plex name home.p1 org concat volume home sd name home.p1.s0 drive UpWindow plex home.p1 len $hl driveoffset $ho plex name usr.p1 org concat volume usr sd name usr.p1.s0 drive UpWindow plex usr.p1 len $ul driveoffset $uo Where $hl, $ho, $ul, and $uo are set as above. Acknowledgements I would like to thank Greg Lehey for writing &vinum.ap; and for providing very helpful comments on early drafts. Several others made helpful suggestions after reviewing later drafts including Dag-Erling Smørgrav, Michael Splendoria, Chern Lee, Stefan Aeschbacher, Fleming Froekjaer, Bernd Walter, Aleksey Baranov, and Doug Swarin.
diff --git a/en_US.ISO8859-1/books/arch-handbook/driverbasics/chapter.sgml b/en_US.ISO8859-1/books/arch-handbook/driverbasics/chapter.sgml index ef42c9257e..2c18ee5f50 100644 --- a/en_US.ISO8859-1/books/arch-handbook/driverbasics/chapter.sgml +++ b/en_US.ISO8859-1/books/arch-handbook/driverbasics/chapter.sgml @@ -1,390 +1,390 @@ Writing FreeBSD Device Drivers This chapter was written by &a.murray; with selections from a variety of sources including the intro(4) man page by &a.joerg;. Introduction This chapter provides a brief introduction to writing device drivers for FreeBSD. A device in this context is a term used mostly for hardware-related stuff that belongs to the system, like disks, printers, or a graphics display with its keyboard. A device driver is the software component of the operating system that controls a specific device. There are also so-called pseudo-devices where a device driver emulates the behaviour of a device in software without any particular underlying hardware. Device drivers can be compiled into the system statically or loaded on demand through the dynamic kernel linker facility `kld'. Most devices in a Unix-like operating system are accessed through device-nodes, sometimes also called special files. These files are usually located under the directory - /dev in the file system hierarchy. Until + /dev in the filesystem hierarchy. Until devfs is fully integrated into FreeBSD, each device node must be created statically and independent of the existence of the associated device driver. Most device nodes on the system are created by running MAKEDEV. Device drivers can roughly be broken down into two categories; character and network device drivers. Dynamic Kernel Linker Facility - KLD The kld interface allows system administrators to dynamically add and remove functionality from a running system. This allows device driver writers to load their new changes into a running kernel without constantly rebooting to test changes. The kld interface is used through the following privileged commands: kldload - loads a new kernel module kldunload - unloads a kernel module kldstat - lists the currently loaded modules Skeleton Layout of a kernel module /* * KLD Skeleton * Inspired by Andrew Reiter's Daemonnews article */ #include <sys/types.h> #include <sys/module.h> #include <sys/systm.h> /* uprintf */ #include <sys/errno.h> #include <sys/param.h> /* defines used in kernel.h */ #include <sys/kernel.h> /* types used in module initialization */ /* * Load handler that deals with the loading and unloading of a KLD. */ static int skel_loader(struct module *m, int what, void *arg) { int err = 0; switch (what) { case MOD_LOAD: /* kldload */ uprintf("Skeleton KLD loaded.\n"); break; case MOD_UNLOAD: uprintf("Skeleton KLD unloaded.\n"); break; default: err = EINVAL; break; } return(err); } /* Declare this module to the rest of the kernel */ static moduledata_t skel_mod = { "skel", skel_loader, NULL }; DECLARE_MODULE(skeleton, skel_mod, SI_SUB_KLD, SI_ORDER_ANY); Makefile FreeBSD provides a makefile include that you can use to quickly compile your kernel addition. SRCS=skeleton.c KMOD=skeleton .include <bsd.kmod.mk> Simply running make with this makefile will create a file skeleton.ko that can be loaded into your system by typing: &prompt.root; kldload -v ./skeleton.ko Accessing a device driver Unix provides a common set of system calls for user applications to use. The upper layers of the kernel dispatch these calls to the corresponding device driver when a user accesses a device node. The /dev/MAKEDEV script makes most of the device nodes for your system but if you are doing your own driver development it may be necessary to create your own device nodes with mknod. Creating static device nodes The mknod command requires four arguments to create a device node. You must specify the name of the device node, the type of device, the major number of the device, and the minor number of the device. Dynamic device nodes The device filesystem, or devfs, provides access to the kernel's device namespace in the global filesystem namespace. This eliminates the problems of potentially having a device driver without a static device node, or a device node without an installed device driver. Devfs is still a work in progress, but it is already working quite nicely. Character Devices A character device driver is one that transfers data directly to and from a user process. This is the most common type of device driver and there are plenty of simple examples in the source tree. This simple example pseudo-device remembers whatever values you write to it and can then supply them back to you when you read from it. /* * Simple `echo' pseudo-device KLD * * Murray Stokely */ #define MIN(a,b) (((a) < (b)) ? (a) : (b)) #include <sys/types.h> #include <sys/module.h> #include <sys/systm.h> /* uprintf */ #include <sys/errno.h> #include <sys/param.h> /* defines used in kernel.h */ #include <sys/kernel.h> /* types used in module initialization */ #include <sys/conf.h> /* cdevsw struct */ #include <sys/uio.h> /* uio struct */ #include <sys/malloc.h> #define BUFFERSIZE 256 /* Function prototypes */ d_open_t echo_open; d_close_t echo_close; d_read_t echo_read; d_write_t echo_write; /* Character device entry points */ static struct cdevsw echo_cdevsw = { echo_open, echo_close, echo_read, echo_write, noioctl, nopoll, nommap, nostrategy, "echo", 33, /* reserved for lkms - /usr/src/sys/conf/majors */ nodump, nopsize, D_TTY, -1 }; typedef struct s_echo { char msg[BUFFERSIZE]; int len; } t_echo; /* vars */ static dev_t sdev; static int len; static int count; static t_echo *echomsg; MALLOC_DECLARE(M_ECHOBUF); MALLOC_DEFINE(M_ECHOBUF, "echobuffer", "buffer for echo module"); /* * This function acts is called by the kld[un]load(2) system calls to * determine what actions to take when a module is loaded or unloaded. */ static int echo_loader(struct module *m, int what, void *arg) { int err = 0; switch (what) { case MOD_LOAD: /* kldload */ sdev = make_dev(&echo_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "echo"); /* kmalloc memory for use by this driver */ /* malloc(256,M_ECHOBUF,M_WAITOK); */ MALLOC(echomsg, t_echo *, sizeof(t_echo), M_ECHOBUF, M_WAITOK); printf("Echo device loaded.\n"); break; case MOD_UNLOAD: destroy_dev(sdev); FREE(echomsg,M_ECHOBUF); printf("Echo device unloaded.\n"); break; default: err = EINVAL; break; } return(err); } int echo_open(dev_t dev, int oflags, int devtype, struct proc *p) { int err = 0; uprintf("Opened device \"echo\" successfully.\n"); return(err); } int echo_close(dev_t dev, int fflag, int devtype, struct proc *p) { uprintf("Closing device \"echo.\"\n"); return(0); } /* * The read function just takes the buf that was saved via * echo_write() and returns it to userland for accessing. * uio(9) */ int echo_read(dev_t dev, struct uio *uio, int ioflag) { int err = 0; int amt; /* How big is this read operation? Either as big as the user wants, or as big as the remaining data */ amt = MIN(uio->uio_resid, (echomsg->len - uio->uio_offset > 0) ? echomsg->len - uio->uio_offset : 0); if ((err = uiomove(echomsg->msg + uio->uio_offset,amt,uio)) != 0) { uprintf("uiomove failed!\n"); } return err; } /* * echo_write takes in a character string and saves it * to buf for later accessing. */ int echo_write(dev_t dev, struct uio *uio, int ioflag) { int err = 0; /* Copy the string in from user memory to kernel memory */ err = copyin(uio->uio_iov->iov_base, echomsg->msg, MIN(uio->uio_iov->iov_len,BUFFERSIZE)); /* Now we need to null terminate */ *(echomsg->msg + MIN(uio->uio_iov->iov_len,BUFFERSIZE)) = 0; /* Record the length */ echomsg->len = MIN(uio->uio_iov->iov_len,BUFFERSIZE); if (err != 0) { uprintf("Write failed: bad address!\n"); } count++; return(err); } DEV_MODULE(echo,echo_loader,NULL); To install this driver you will first need to make a node on your filesystem with a command such as: &prompt.root; mknod /dev/echo c 33 0 With this driver loaded you should now be able to type something like: &prompt.root; echo -n "Test Data" > /dev/echo &prompt.root; cat /dev/echo Test Data Real hardware devices in the next chapter.. Additional Resources Dynamic Kernel Linker (KLD) Facility Programming Tutorial - Daemonnews October 2000 How to Write Kernel Drivers with NEWBUS - Daemonnews July 2000 Network Drivers Drivers for network devices do not use device nodes in order to be accessed. Their selection is based on other decisions made inside the kernel and instead of calling open(), use of a network device is generally introduced by using the system call socket(2). man ifnet(), loopback device, Bill Paul's drivers, etc.. diff --git a/en_US.ISO8859-1/books/developers-handbook/driverbasics/chapter.sgml b/en_US.ISO8859-1/books/developers-handbook/driverbasics/chapter.sgml index ef42c9257e..2c18ee5f50 100644 --- a/en_US.ISO8859-1/books/developers-handbook/driverbasics/chapter.sgml +++ b/en_US.ISO8859-1/books/developers-handbook/driverbasics/chapter.sgml @@ -1,390 +1,390 @@ Writing FreeBSD Device Drivers This chapter was written by &a.murray; with selections from a variety of sources including the intro(4) man page by &a.joerg;. Introduction This chapter provides a brief introduction to writing device drivers for FreeBSD. A device in this context is a term used mostly for hardware-related stuff that belongs to the system, like disks, printers, or a graphics display with its keyboard. A device driver is the software component of the operating system that controls a specific device. There are also so-called pseudo-devices where a device driver emulates the behaviour of a device in software without any particular underlying hardware. Device drivers can be compiled into the system statically or loaded on demand through the dynamic kernel linker facility `kld'. Most devices in a Unix-like operating system are accessed through device-nodes, sometimes also called special files. These files are usually located under the directory - /dev in the file system hierarchy. Until + /dev in the filesystem hierarchy. Until devfs is fully integrated into FreeBSD, each device node must be created statically and independent of the existence of the associated device driver. Most device nodes on the system are created by running MAKEDEV. Device drivers can roughly be broken down into two categories; character and network device drivers. Dynamic Kernel Linker Facility - KLD The kld interface allows system administrators to dynamically add and remove functionality from a running system. This allows device driver writers to load their new changes into a running kernel without constantly rebooting to test changes. The kld interface is used through the following privileged commands: kldload - loads a new kernel module kldunload - unloads a kernel module kldstat - lists the currently loaded modules Skeleton Layout of a kernel module /* * KLD Skeleton * Inspired by Andrew Reiter's Daemonnews article */ #include <sys/types.h> #include <sys/module.h> #include <sys/systm.h> /* uprintf */ #include <sys/errno.h> #include <sys/param.h> /* defines used in kernel.h */ #include <sys/kernel.h> /* types used in module initialization */ /* * Load handler that deals with the loading and unloading of a KLD. */ static int skel_loader(struct module *m, int what, void *arg) { int err = 0; switch (what) { case MOD_LOAD: /* kldload */ uprintf("Skeleton KLD loaded.\n"); break; case MOD_UNLOAD: uprintf("Skeleton KLD unloaded.\n"); break; default: err = EINVAL; break; } return(err); } /* Declare this module to the rest of the kernel */ static moduledata_t skel_mod = { "skel", skel_loader, NULL }; DECLARE_MODULE(skeleton, skel_mod, SI_SUB_KLD, SI_ORDER_ANY); Makefile FreeBSD provides a makefile include that you can use to quickly compile your kernel addition. SRCS=skeleton.c KMOD=skeleton .include <bsd.kmod.mk> Simply running make with this makefile will create a file skeleton.ko that can be loaded into your system by typing: &prompt.root; kldload -v ./skeleton.ko Accessing a device driver Unix provides a common set of system calls for user applications to use. The upper layers of the kernel dispatch these calls to the corresponding device driver when a user accesses a device node. The /dev/MAKEDEV script makes most of the device nodes for your system but if you are doing your own driver development it may be necessary to create your own device nodes with mknod. Creating static device nodes The mknod command requires four arguments to create a device node. You must specify the name of the device node, the type of device, the major number of the device, and the minor number of the device. Dynamic device nodes The device filesystem, or devfs, provides access to the kernel's device namespace in the global filesystem namespace. This eliminates the problems of potentially having a device driver without a static device node, or a device node without an installed device driver. Devfs is still a work in progress, but it is already working quite nicely. Character Devices A character device driver is one that transfers data directly to and from a user process. This is the most common type of device driver and there are plenty of simple examples in the source tree. This simple example pseudo-device remembers whatever values you write to it and can then supply them back to you when you read from it. /* * Simple `echo' pseudo-device KLD * * Murray Stokely */ #define MIN(a,b) (((a) < (b)) ? (a) : (b)) #include <sys/types.h> #include <sys/module.h> #include <sys/systm.h> /* uprintf */ #include <sys/errno.h> #include <sys/param.h> /* defines used in kernel.h */ #include <sys/kernel.h> /* types used in module initialization */ #include <sys/conf.h> /* cdevsw struct */ #include <sys/uio.h> /* uio struct */ #include <sys/malloc.h> #define BUFFERSIZE 256 /* Function prototypes */ d_open_t echo_open; d_close_t echo_close; d_read_t echo_read; d_write_t echo_write; /* Character device entry points */ static struct cdevsw echo_cdevsw = { echo_open, echo_close, echo_read, echo_write, noioctl, nopoll, nommap, nostrategy, "echo", 33, /* reserved for lkms - /usr/src/sys/conf/majors */ nodump, nopsize, D_TTY, -1 }; typedef struct s_echo { char msg[BUFFERSIZE]; int len; } t_echo; /* vars */ static dev_t sdev; static int len; static int count; static t_echo *echomsg; MALLOC_DECLARE(M_ECHOBUF); MALLOC_DEFINE(M_ECHOBUF, "echobuffer", "buffer for echo module"); /* * This function acts is called by the kld[un]load(2) system calls to * determine what actions to take when a module is loaded or unloaded. */ static int echo_loader(struct module *m, int what, void *arg) { int err = 0; switch (what) { case MOD_LOAD: /* kldload */ sdev = make_dev(&echo_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "echo"); /* kmalloc memory for use by this driver */ /* malloc(256,M_ECHOBUF,M_WAITOK); */ MALLOC(echomsg, t_echo *, sizeof(t_echo), M_ECHOBUF, M_WAITOK); printf("Echo device loaded.\n"); break; case MOD_UNLOAD: destroy_dev(sdev); FREE(echomsg,M_ECHOBUF); printf("Echo device unloaded.\n"); break; default: err = EINVAL; break; } return(err); } int echo_open(dev_t dev, int oflags, int devtype, struct proc *p) { int err = 0; uprintf("Opened device \"echo\" successfully.\n"); return(err); } int echo_close(dev_t dev, int fflag, int devtype, struct proc *p) { uprintf("Closing device \"echo.\"\n"); return(0); } /* * The read function just takes the buf that was saved via * echo_write() and returns it to userland for accessing. * uio(9) */ int echo_read(dev_t dev, struct uio *uio, int ioflag) { int err = 0; int amt; /* How big is this read operation? Either as big as the user wants, or as big as the remaining data */ amt = MIN(uio->uio_resid, (echomsg->len - uio->uio_offset > 0) ? echomsg->len - uio->uio_offset : 0); if ((err = uiomove(echomsg->msg + uio->uio_offset,amt,uio)) != 0) { uprintf("uiomove failed!\n"); } return err; } /* * echo_write takes in a character string and saves it * to buf for later accessing. */ int echo_write(dev_t dev, struct uio *uio, int ioflag) { int err = 0; /* Copy the string in from user memory to kernel memory */ err = copyin(uio->uio_iov->iov_base, echomsg->msg, MIN(uio->uio_iov->iov_len,BUFFERSIZE)); /* Now we need to null terminate */ *(echomsg->msg + MIN(uio->uio_iov->iov_len,BUFFERSIZE)) = 0; /* Record the length */ echomsg->len = MIN(uio->uio_iov->iov_len,BUFFERSIZE); if (err != 0) { uprintf("Write failed: bad address!\n"); } count++; return(err); } DEV_MODULE(echo,echo_loader,NULL); To install this driver you will first need to make a node on your filesystem with a command such as: &prompt.root; mknod /dev/echo c 33 0 With this driver loaded you should now be able to type something like: &prompt.root; echo -n "Test Data" > /dev/echo &prompt.root; cat /dev/echo Test Data Real hardware devices in the next chapter.. Additional Resources Dynamic Kernel Linker (KLD) Facility Programming Tutorial - Daemonnews October 2000 How to Write Kernel Drivers with NEWBUS - Daemonnews July 2000 Network Drivers Drivers for network devices do not use device nodes in order to be accessed. Their selection is based on other decisions made inside the kernel and instead of calling open(), use of a network device is generally introduced by using the system call socket(2). man ifnet(), loopback device, Bill Paul's drivers, etc.. diff --git a/en_US.ISO8859-1/books/developers-handbook/kerneldebug/chapter.sgml b/en_US.ISO8859-1/books/developers-handbook/kerneldebug/chapter.sgml index eeacbb817f..b401d9197d 100644 --- a/en_US.ISO8859-1/books/developers-handbook/kerneldebug/chapter.sgml +++ b/en_US.ISO8859-1/books/developers-handbook/kerneldebug/chapter.sgml @@ -1,649 +1,649 @@ Kernel Debugging Contributed by &a.paul; and &a.joerg; Debugging a Kernel Crash Dump with <command>gdb</command> Here are some instructions for getting kernel debugging working on a crash dump. They assume that you have enough swap space for a crash dump. Typically you want to specify one of the swap devices specified in /etc/fstab. Dumps to non-swap devices, tapes for example, are currently not supported. Use the &man.dumpon.8; command to tell the kernel where to dump to (note that this will have to be done after configuring the partition in question as swap space via &man.swapon.8;). This is normally arranged by setting the dumpdev variable in /etc/rc.conf. Alternatively, you can hard-code the dump device via the dump clause in the config line of your kernel configuration file. This approach is deprecated and should be used only if you want a crash dump from a kernel that crashes during booting. In the following, the term gdb refers to the debugger gdb run in kernel debug mode. This can be accomplished by starting the gdb with the option . In kernel debug mode, gdb changes its prompt to (kgdb). If you are using FreeBSD 3 or earlier, you should make a stripped copy of the debug kernel, rather than installing the large debug kernel itself: &prompt.root; cp kernel kernel.debug &prompt.root; strip -g kernel This stage is not necessary, but it is recommended. (In FreeBSD 4 and later releases this step is performed automatically at the end of the kernel make process.) When the kernel has been stripped, either automatically or by using the commands above, you may install it as usual by typing make install. Note that older releases of FreeBSD (up to but not including 3.1) used a.out kernels by default, which must have their symbol tables permanently resident in physical memory. With the larger symbol table in an unstripped debug kernel, this is wasteful. Recent FreeBSD releases use ELF kernels where this is no longer a problem. If you are testing a new kernel, for example by typing the new kernel's name at the boot prompt, but need to boot a different one in order to get your system up and running again, boot it only into single user state using the flag at the boot prompt, and then perform the following steps: &prompt.root; fsck -p -&prompt.root; mount -a -t ufs # so your file system for /var/crash is writable +&prompt.root; mount -a -t ufs # so your filesystem for /var/crash is writable &prompt.root; savecore -N /kernel.panicked /var/crash &prompt.root; exit # ...to multi-user This instructs &man.savecore.8; to use another kernel for symbol name extraction. It would otherwise default to the currently running kernel and most likely not do anything at all since the crash dump and the kernel symbols differ. Now, after a crash dump, go to /sys/compile/WHATEVER and run gdb . From gdb do: symbol-file kernel.debug exec-file /var/crash/kernel.0 core-file /var/crash/vmcore.0 and voila, you can debug the crash dump using the kernel sources just like you can for any other program. Here is a script log of a gdb session illustrating the procedure. Long lines have been folded to improve readability, and the lines are numbered for reference. Despite this, it is a real-world error trace taken during the development of the pcvt console driver. 1:Script started on Fri Dec 30 23:15:22 1994 2:&prompt.root; cd /sys/compile/URIAH 3:&prompt.root; gdb -k kernel /var/crash/vmcore.1 4:Reading symbol data from /usr/src/sys/compile/URIAH/kernel ...done. 5:IdlePTD 1f3000 6:panic: because you said to! 7:current pcb at 1e3f70 8:Reading in symbols for ../../i386/i386/machdep.c...done. 9:(kgdb) where 10:#0 boot (arghowto=256) (../../i386/i386/machdep.c line 767) 11:#1 0xf0115159 in panic () 12:#2 0xf01955bd in diediedie () (../../i386/i386/machdep.c line 698) 13:#3 0xf010185e in db_fncall () 14:#4 0xf0101586 in db_command (-266509132, -266509516, -267381073) 15:#5 0xf0101711 in db_command_loop () 16:#6 0xf01040a0 in db_trap () 17:#7 0xf0192976 in kdb_trap (12, 0, -272630436, -266743723) 18:#8 0xf019d2eb in trap_fatal (...) 19:#9 0xf019ce60 in trap_pfault (...) 20:#10 0xf019cb2f in trap (...) 21:#11 0xf01932a1 in exception:calltrap () 22:#12 0xf0191503 in cnopen (...) 23:#13 0xf0132c34 in spec_open () 24:#14 0xf012d014 in vn_open () 25:#15 0xf012a183 in open () 26:#16 0xf019d4eb in syscall (...) 27:(kgdb) up 10 28:Reading in symbols for ../../i386/i386/trap.c...done. 29:#10 0xf019cb2f in trap (frame={tf_es = -260440048, tf_ds = 16, tf_\ 30:edi = 3072, tf_esi = -266445372, tf_ebp = -272630356, tf_isp = -27\ 31:2630396, tf_ebx = -266427884, tf_edx = 12, tf_ecx = -266427884, tf\ 32:_eax = 64772224, tf_trapno = 12, tf_err = -272695296, tf_eip = -26\ 33:6672343, tf_cs = -266469368, tf_eflags = 66066, tf_esp = 3072, tf_\ 34:ss = -266427884}) (../../i386/i386/trap.c line 283) 35:283 (void) trap_pfault(&frame, FALSE); 36:(kgdb) frame frame->tf_ebp frame->tf_eip 37:Reading in symbols for ../../i386/isa/pcvt/pcvt_drv.c...done. 38:#0 0xf01ae729 in pcopen (dev=3072, flag=3, mode=8192, p=(struct p\ 39:roc *) 0xf07c0c00) (../../i386/isa/pcvt/pcvt_drv.c line 403) 40:403 return ((*linesw[tp->t_line].l_open)(dev, tp)); 41:(kgdb) list 42:398 43:399 tp->t_state |= TS_CARR_ON; 44:400 tp->t_cflag |= CLOCAL; /* cannot be a modem (:-) */ 45:401 46:402 #if PCVT_NETBSD || (PCVT_FREEBSD >= 200) 47:403 return ((*linesw[tp->t_line].l_open)(dev, tp)); 48:404 #else 49:405 return ((*linesw[tp->t_line].l_open)(dev, tp, flag)); 50:406 #endif /* PCVT_NETBSD || (PCVT_FREEBSD >= 200) */ 51:407 } 52:(kgdb) print tp 53:Reading in symbols for ../../i386/i386/cons.c...done. 54:$1 = (struct tty *) 0x1bae 55:(kgdb) print tp->t_line 56:$2 = 1767990816 57:(kgdb) up 58:#1 0xf0191503 in cnopen (dev=0x00000000, flag=3, mode=8192, p=(st\ 59:ruct proc *) 0xf07c0c00) (../../i386/i386/cons.c line 126) 60: return ((*cdevsw[major(dev)].d_open)(dev, flag, mode, p)); 61:(kgdb) up 62:#2 0xf0132c34 in spec_open () 63:(kgdb) up 64:#3 0xf012d014 in vn_open () 65:(kgdb) up 66:#4 0xf012a183 in open () 67:(kgdb) up 68:#5 0xf019d4eb in syscall (frame={tf_es = 39, tf_ds = 39, tf_edi =\ 69: 2158592, tf_esi = 0, tf_ebp = -272638436, tf_isp = -272629788, tf\ 70:_ebx = 7086, tf_edx = 1, tf_ecx = 0, tf_eax = 5, tf_trapno = 582, \ 71:tf_err = 582, tf_eip = 75749, tf_cs = 31, tf_eflags = 582, tf_esp \ 72:= -272638456, tf_ss = 39}) (../../i386/i386/trap.c line 673) 73:673 error = (*callp->sy_call)(p, args, rval); 74:(kgdb) up 75:Initial frame selected; you cannot go up. 76:(kgdb) quit 77:&prompt.root; exit 78:exit 79: 80:Script done on Fri Dec 30 23:18:04 1994 Comments to the above script: line 6: This is a dump taken from within DDB (see below), hence the panic comment because you said to!, and a rather long stack trace; the initial reason for going into DDB has been a page fault trap though. line 20: This is the location of function trap() in the stack trace. line 36: Force usage of a new stack frame; this is no longer necessary. The stack frames are supposed to point to the right locations now, even in case of a trap. From looking at the code in source line 403, there is a high probability that either the pointer access for tp was messed up, or the array access was out of bounds. line 52: The pointer looks suspicious, but happens to be a valid address. line 56: However, it obviously points to garbage, so we have found our error! (For those unfamiliar with that particular piece of code: tp->t_line refers to the line discipline of the console device here, which must be a rather small integer number.) Debugging a Crash Dump with DDD Examining a kernel crash dump with a graphical debugger like ddd is also possible (you will need to install the devel/ddd port in order to use the ddd debugger). Add the option to the ddd command line you would use normally. For example; &prompt.root; ddd -k /var/crash/kernel.0 /var/crash/vmcore.0 You should then be able to go about looking at the crash dump using ddd's graphical interface. Post-Mortem Analysis of a Dump What do you do if a kernel dumped core but you did not expect it, and it is therefore not compiled using config -g? Not everything is lost here. Do not panic! Of course, you still need to enable crash dumps. See above for the options you have to specify in order to do this. Go to your kernel config directory (/usr/src/sys/arch/conf) and edit your configuration file. Uncomment (or add, if it does not exist) the following line: makeoptions DEBUG=-g #Build kernel with gdb(1) debug symbols Rebuild the kernel. Due to the time stamp change on the Makefile, there some other object files will be rebuilt, for example trap.o. With a bit of luck, the added option will not change anything for the generated code, so you will finally get a new kernel with similar code to the faulting one but some debugging symbols. You should at least verify the old and new sizes with the &man.size.1; command. If there is a mismatch, you probably need to give up here. Go and examine the dump as described above. The debugging symbols might be incomplete for some places, as can be seen in the stack trace in the example above where some functions are displayed without line numbers and argument lists. If you need more debugging symbols, remove the appropriate object files, recompile the kernel again and repeat the gdb session until you know enough. All this is not guaranteed to work, but it will do it fine in most cases. On-Line Kernel Debugging Using DDB While gdb as an off-line debugger provides a very high level of user interface, there are some things it cannot do. The most important ones being breakpointing and single-stepping kernel code. If you need to do low-level debugging on your kernel, there is an on-line debugger available called DDB. It allows setting of breakpoints, single-stepping kernel functions, examining and changing kernel variables, etc. However, it cannot access kernel source files, and only has access to the global and static symbols, not to the full debug information like gdb does. To configure your kernel to include DDB, add the option line options DDB to your config file, and rebuild. (See The FreeBSD Handbook for details on configuring the FreeBSD kernel). If you have an older version of the boot blocks, your debugger symbols might not be loaded at all. Update the boot blocks; the recent ones load the DDB symbols automagically. Once your DDB kernel is running, there are several ways to enter DDB. The first, and earliest way is to type the boot flag right at the boot prompt. The kernel will start up in debug mode and enter DDB prior to any device probing. Hence you can even debug the device probe/attach functions. The second scenario is to drop to the debugger once the system has booted. There are two simple ways to accomplish this. If you would like to break to the debugger from the command prompt, simply type the command: &prompt.root; sysctl debug.enter_debugger=ddb Alternatively, if you are at the system console, you may use a hot-key on the keyboard. The default break-to-debugger sequence is Ctrl AltESC. For syscons, this sequence can be remapped and some of the distributed maps out there do this, so check to make sure you know the right sequence to use. There is an option available for serial consoles that allows the use of a serial line BREAK on the console line to enter DDB (options BREAK_TO_DEBUGGER in the kernel config file). It is not the default since there are a lot of serial adapters around that gratuitously generate a BREAK condition, for example when pulling the cable. The third way is that any panic condition will branch to DDB if the kernel is configured to use it. For this reason, it is not wise to configure a kernel with DDB for a machine running unattended. The DDB commands roughly resemble some gdb commands. The first thing you probably need to do is to set a breakpoint: b function-name b address Numbers are taken hexadecimal by default, but to make them distinct from symbol names; hexadecimal numbers starting with the letters a-f need to be preceded with 0x (this is optional for other numbers). Simple expressions are allowed, for example: function-name + 0x103. To continue the operation of an interrupted kernel, simply type: c To get a stack trace, use: trace Note that when entering DDB via a hot-key, the kernel is currently servicing an interrupt, so the stack trace might be not of much use to you. If you want to remove a breakpoint, use del del address-expression The first form will be accepted immediately after a breakpoint hit, and deletes the current breakpoint. The second form can remove any breakpoint, but you need to specify the exact address; this can be obtained from: show b To single-step the kernel, try: s This will step into functions, but you can make DDB trace them until the matching return statement is reached by: n This is different from gdb's next statement; it is like gdb's finish. To examine data from memory, use (for example): x/wx 0xf0133fe0,40 x/hd db_symtab_space x/bc termbuf,10 x/s stringbuf for word/halfword/byte access, and hexadecimal/decimal/character/ string display. The number after the comma is the object count. To display the next 0x10 items, simply use: x ,10 Similarly, use x/ia foofunc,10 to disassemble the first 0x10 instructions of foofunc, and display them along with their offset from the beginning of foofunc. To modify memory, use the write command: w/b termbuf 0xa 0xb 0 w/w 0xf0010030 0 0 The command modifier (b/h/w) specifies the size of the data to be written, the first following expression is the address to write to and the remainder is interpreted as data to write to successive memory locations. If you need to know the current registers, use: show reg Alternatively, you can display a single register value by e.g. p $eax and modify it by: set $eax new-value Should you need to call some kernel functions from DDB, simply say: call func(arg1, arg2, ...) The return value will be printed. For a &man.ps.1; style summary of all running processes, use: ps Now you have examined why your kernel failed, and you wish to reboot. Remember that, depending on the severity of previous malfunctioning, not all parts of the kernel might still be working as expected. Perform one of the following actions to shut down and reboot your system: panic This will cause your kernel to dump core and reboot, so you can later analyze the core on a higher level with gdb. This command usually must be followed by another continue statement. call boot(0) Which might be a good way to cleanly shut down the running system, sync() all disks, and finally reboot. As long as - the disk and file system interfaces of the kernel are not damaged, this + the disk and filesystem interfaces of the kernel are not damaged, this might be a good way for an almost clean shutdown. call cpu_reset() This is the final way out of disaster and almost the same as hitting the Big Red Button. If you need a short command summary, simply type: help However, it is highly recommended to have a printed copy of the &man.ddb.4; manual page ready for a debugging session. Remember that it is hard to read the on-line manual while single-stepping the kernel. On-Line Kernel Debugging Using Remote GDB This feature has been supported since FreeBSD 2.2, and it is actually a very neat one. GDB has already supported remote debugging for a long time. This is done using a very simple protocol along a serial line. Unlike the other methods described above, you will need two machines for doing this. One is the host providing the debugging environment, including all the sources, and a copy of the kernel binary with all the symbols in it, and the other one is the target machine that simply runs a similar copy of the very same kernel (but stripped of the debugging information). You should configure the kernel in question with config -g, include into the configuration, and compile it as usual. This gives a large binary, due to the debugging information. Copy this kernel to the target machine, strip the debugging symbols off with strip -x, and boot it using the boot option. Connect the serial line of the target machine that has "flags 080" set on its sio device to any serial line of the debugging host. Now, on the debugging machine, go to the compile directory of the target kernel, and start gdb: &prompt.user; gdb -k kernel GDB is free software and you are welcome to distribute copies of it under certain conditions; type "show copying" to see the conditions. There is absolutely no warranty for GDB; type "show warranty" for details. GDB 4.16 (i386-unknown-freebsd), Copyright 1996 Free Software Foundation, Inc... (kgdb) Initialize the remote debugging session (assuming the first serial port is being used) by: (kgdb) target remote /dev/cuaa0 Now, on the target host (the one that entered DDB right before even starting the device probe), type: Debugger("Boot flags requested debugger") Stopped at Debugger+0x35: movb $0, edata+0x51bc db> gdb DDB will respond with: Next trap will enter GDB remote protocol mode Every time you type gdb, the mode will be toggled between remote GDB and local DDB. In order to force a next trap immediately, simply type s (step). Your hosting GDB will now gain control over the target kernel: Remote debugging using /dev/cuaa0 Debugger (msg=0xf01b0383 "Boot flags requested debugger") at ../../i386/i386/db_interface.c:257 (kgdb) You can use this session almost as any other GDB session, including full access to the source, running it in gud-mode inside an Emacs window (which gives you an automatic source code display in another Emacs window), etc. Debugging Loadable Modules Using GDB When debugging a panic that occurred within a module, or using remote GDB against a machine that uses dynamic modules, you need to tell GDB how to obtain symbol information for those modules. First, you need to build the module(s) with debugging information: &prompt.root; cd /sys/modules/linux &prompt.root; make clean; make COPTS=-g If you are using remote GDB, you can run kldstat on the target machine to find out where the module was loaded: &prompt.root; kldstat Id Refs Address Size Name 1 4 0xc0100000 1c1678 kernel 2 1 0xc0a9e000 6000 linprocfs.ko 3 1 0xc0ad7000 2000 warp_saver.ko 4 1 0xc0adc000 11000 linux.ko If you are debugging a crash dump, you will need to walk the linker_files list, starting at linker_files->tqh_first and following the link.tqe_next pointers until you find the entry with the filename you are looking for. The address member of that entry is the load address of the module. Next, you need to find out the offset of the text section within the module: &prompt.root; objdump --section-headers /sys/modules/linux/linux.ko | grep text 3 .rel.text 000016e0 000038e0 000038e0 000038e0 2**2 10 .text 00007f34 000062d0 000062d0 000062d0 2**2 The one you want is the .text section, section 10 in the above example. The fourth hexadecimal field (sixth field overall) is the offset of the text section within the file. Add this offset to the load address of the module to obtain the relocation address for the module's code. In our example, we get 0xc0adc000 + 0x62d0 = 0xc0ae22d0. Use the add-symbol-file command in GDB to tell the debugger about the module: (kgdb) add-symbol-file /sys/modules/linux/linux.ko 0xc0ae22d0 add symbol table from file "/sys/modules/linux/linux.ko" at text_addr = 0xc0ae22d0? (y or n) y Reading symbols from /sys/modules/linux/linux.ko...done. (kgdb) You should now have access to all the symbols in the module. Debugging a Console Driver Since you need a console driver to run DDB on, things are more complicated if the console driver itself is failing. You might remember the use of a serial console (either with modified boot blocks, or by specifying at the Boot: prompt), and hook up a standard terminal onto your first serial port. DDB works on any configured console driver, including a serial console. diff --git a/en_US.ISO8859-1/books/developers-handbook/secure/chapter.sgml b/en_US.ISO8859-1/books/developers-handbook/secure/chapter.sgml index a8c1eb3e18..351b0cc8d3 100644 --- a/en_US.ISO8859-1/books/developers-handbook/secure/chapter.sgml +++ b/en_US.ISO8859-1/books/developers-handbook/secure/chapter.sgml @@ -1,517 +1,517 @@ Secure Programming This chapter was written by &a.murray;. Synopsis This chapter describes some of the security issues that have plagued Unix programmers for decades and some of the new tools available to help programmers avoid writing exploitable code. Secure Design Methodology Writing secure applications takes a very scrutinous and pessimistic outlook on life. Applications should be run with the principle of least privilege so that no process is ever running with more than the bare minimum access that it needs to accomplish its function. Previously tested code should be reused whenever possible to avoid common mistakes that others may have already fixed. One of the pitfalls of the Unix environment is how easy it is to make assumptions about the sanity of the environment. Applications should never trust user input (in all its forms), system resources, inter-process communication, or the timing of events. Unix processes do not execute synchronously so logical operations are rarely atomic. Buffer Overflows Buffer Overflows have been around since the very beginnings of the Von-Neuman architecture. buffer overflow Von-Neuman They first gained widespread notoriety in 1988 with the Morris Internet worm. Unfortunately, the same basic attack remains Morris Internet worm effective today. Of the 17 CERT security advisories of 1999, 10 CERTsecurity advisories of them were directly caused by buffer-overflow software bugs. By far the most common type of buffer overflow attack is based on corrupting the stack. stack arguments Most modern computer systems use a stack to pass arguments to procedures and to store local variables. A stack is a last in first out (LIFO) buffer in the high memory area of a process image. When a program invokes a function a new "stack frame" is LIFO process image stack pointer created. This stack frame consists of the arguments passed to the function as well as a dynamic amount of local variable space. The "stack pointer" is a register that holds the current stack frame stack pointer location of the top of the stack. Since this value is constantly changing as new values are pushed onto the top of the stack, many implementations also provide a "frame pointer" that is located near the beginning of a stack frame so that local variables can more easily be addressed relative to this value. The return address for function frame pointer process image frame pointer return address stack-overflow calls is also stored on the stack, and this is the cause of stack-overflow exploits since overflowing a local variable in a function can overwrite the return address of that function, potentially allowing a malicious user to execute any code he or she wants. Although stack-based attacks are by far the most common, it would also be possible to overrun the stack with a heap-based (malloc/free) attack. The C programming language does not perform automatic bounds checking on arrays or pointers as many other languages do. In addition, the standard C library is filled with a handful of very dangerous functions. strcpy(char *dest, const char *src) May overflow the dest buffer strcat(char *dest, const char *src) May overflow the dest buffer getwd(char *buf) May overflow the buf buffer gets(char *s) May overflow the s buffer [vf]scanf(const char *format, ...) May overflow its arguments. realpath(char *path, char resolved_path[]) May overflow the path buffer [v]sprintf(char *str, const char *format, ...) May overflow the str buffer. Example Buffer Overflow The following example code contains a buffer overflow designed to overwrite the return address and skip the instruction immediately following the function call. (Inspired by ) #include stdio.h void manipulate(char *buffer) { char newbuffer[80]; strcpy(newbuffer,buffer); } int main() { char ch,buffer[4096]; int i=0; while ((buffer[i++] = getchar()) != '\n') {}; i=1; manipulate(buffer); i=2; printf("The value of i is : %d\n",i); return 0; } Let us examine what the memory image of this process would look like if we were to input 160 spaces into our little program before hitting return. [XXX figure here!] Obviously more malicious input can be devised to execute actual compiled instructions (such as exec(/bin/sh)). Avoiding Buffer Overflows The most straightforward solution to the problem of stack-overflows is to always use length restricted memory and string copy functions. strncpy and strncat are part of the standard C library. string copy functions strncpy string copy functions strncat These functions accept a length value as a parameter which should be no larger than the size of the destination buffer. These functions will then copy up to `length' bytes from the source to the destination. However there are a number of problems with these functions. Neither function guarantees NUL termination if the size of the input buffer is as large as the NUL termination destination. The length parameter is also used inconsistently between strncpy and strncat so it is easy for programmers to get confused as to their proper usage. There is also a significant performance loss compared to strcpy when copying a short string into a large buffer since strncpy NUL fills up the size specified. In OpenBSD, another memory copy implementation has been OpenBSD created to get around these problem. The strlcpy and strlcat functions guarantee that they will always null terminate the destination string when given a non-zero length argument. For more information about these functions see . The OpenBSD strlcpy and strlcat instructions have been in FreeBSD since 3.3. string copy functions strlcpy string copy functions strlcat Compiler based run-time bounds checking bounds checking compiler-based Unfortunately there is still a very large assortment of code in public use which blindly copies memory around without using any of the bounded copy routines we just discussed. Fortunately, there is another solution. Several compiler add-ons and libraries exist to do Run-time bounds checking in C/C++. StackGuard gcc StackGuard is one such add-on that is implemented as a small patch to the gcc code generator. From the StackGuard website:
"StackGuard detects and defeats stack smashing attacks by protecting the return address on the stack from being altered. StackGuard places a "canary" word next to the return address when a function is called. If the canary word has been altered when the function returns, then a stack smashing attack has been attempted, and the program responds by emitting an intruder alert into syslog, and then halts."
"StackGuard is implemented as a small patch to the gcc code generator, specifically the function_prolog() and function_epilog() routines. function_prolog() has been enhanced to lay down canaries on the stack when functions start, and function_epilog() checks canary integrity when the function exits. Any attempt at corrupting the return address is thus detected before the function returns."
 buffer overflow Recompiling your application with StackGuard is an effective means of stopping most buffer-overflow attacks, but it can still be compromised. Library based run-time bounds checking bounds checking library-based Compiler-based mechanisms are completely useless for binary-only software for which you cannot recompile. For these situations there are a number of libraries which re-implement the unsafe functions of the C-library (strcpy, fscanf, getwd, etc..) and ensure that these functions can never write past the stack pointer. libsafe libverify libparnoia Unfortunately these library-based defenses have a number of shortcomings. These libraries only protect against a very small set of security related issues and they neglect to fix the actual problem. These defenses may fail if the application was compiled with -fomit-frame-pointer. Also, the LD_PRELOAD and LD_LIBRARY_PATH environment variables can be overwritten/unset by the user. SetUID issues seteuid There are at least 6 different IDs associated with any given process. Because of this you have to be very careful with the access that your process has at any given time. In particular, all seteuid applications should give up their privileges as soon as it is no longer required. user IDs real user ID user IDs effective user ID The real user ID can only be changed by a superuser process. The login program sets this when a user initially logs in and it is seldom changed. The effective user ID is set by the exec() functions if a program has its seteuid bit set. An application can call seteuid() at any time to set the effective user ID to either the real user ID or the saved set-user-ID. When the effective user ID is set by exec() functions, the previous value is saved in the saved set-user-ID. Limiting your program's environment chroot() The traditional method of restricting a process is with the chroot() system call. This system call changes the root directory from which all other paths are referenced for a process and any child processes. For this call to succeed the process must have execute (search) permission on the directory being referenced. The new environment does not actually take effect until you chdir() into your new environment. It should also be noted that a process can easily break out of a chroot environment if it has root privilege. This could be accomplished by creating device nodes to read kernel memory, attaching a debugger to a process outside of the jail, or in many other creative ways. The behavior of the chroot() system call can be controlled somewhat with the kern.chroot_allow_open_directories sysctl variable. When this value is set to 0, chroot() will fail with EPERM if there are any directories open. If set to the default value of 1, then chroot() will fail with EPERM if there are any directories open and the process is already subject to a chroot() call. For any other value, the check for open directories will be bypassed completely. FreeBSD's jail functionality jail The concept of a Jail extends upon the chroot() by limiting the powers of the superuser to create a true `virtual server'. Once a prison is setup all network communication must take place through the specified IP address, and the power of "root privilege" in this jail is severely constrained. While in a prison, any tests of superuser power within the kernel using the suser() call will fail. However, some calls to suser() have been changed to a new interface suser_xxx(). This function is responsible for recognizing or denying access to superuser power for imprisoned processes. A superuser process within a jailed environment has the power to: Manipulate credential with setuid, seteuid, setgid, setegid, setgroups, setreuid, setregid, setlogin Set resource limits with setrlimit Modify some sysctl nodes (kern.hostname) chroot() Set flags on a vnode: chflags, fchflags Set attributes of a vnode such as file permission, owner, group, size, access time, and modification time. Bind to privileged ports in the Internet domain (ports < 1024) Jail is a very useful tool for running applications in a secure environment but it does have some shortcomings. Currently, the IPC mechanisms have not been converted to the suser_xxx so applications such as MySQL cannot be run within a jail. Superuser access may have a very limited meaning within a jail, but there is no way to specify exactly what "very limited" means. POSIX.1e Process Capabilities POSIX.1e Process Capabilities TrustedBSD Posix has released a working draft that adds event auditing, access control lists, fine grained privileges, information labeling, and mandatory access control. This is a work in progress and is the focus of the TrustedBSD project. Some of the initial work has been committed to FreeBSD-current (cap_set_proc(3)). Trust An application should never assume that anything about the users environment is sane. This includes (but is certainly not limited to): user input, signals, environment variables, - resources, IPC, mmaps, the file system working directory, file + resources, IPC, mmaps, the filesystem working directory, file descriptors, the # of open files, etc. positive filtering data validation You should never assume that you can catch all forms of invalid input that a user might supply. Instead, your application should use positive filtering to only allow a specific subset of inputs that you deem safe. Improper data validation has been the cause of many exploits, especially with CGI scripts on the world wide web. For filenames you need to be extra careful about paths ("../", "/"), symbolic links, and shell escape characters. Perl Taint mode Perl has a really cool feature called "Taint" mode which can be used to prevent scripts from using data derived outside the program in an unsafe way. This mode will check command line arguments, environment variables, locale information, the results of certain syscalls (readdir(), readlink(), getpwxxx(), and all file input. Race Conditions A race condition is anomalous behavior caused by the unexpected dependence on the relative timing of events. In other words, a programmer incorrectly assumed that a particular event would always happen before another. race conditions signals race conditions access checks race conditions file opens Some of the common causes of race conditions are signals, access checks, and file opens. Signals are asynchronous events by nature so special care must be taken in dealing with them. Checking access with access(2) then open(2) is clearly non-atomic. Users can move files in between the two calls. Instead, privileged applications should seteuid() and then call open() directly. Along the same lines, an application should always set a proper umask before open() to obviate the need for spurious chmod() calls. diff --git a/en_US.ISO8859-1/books/developers-handbook/tools/chapter.sgml b/en_US.ISO8859-1/books/developers-handbook/tools/chapter.sgml index 96dab86aa8..3addb790be 100644 --- a/en_US.ISO8859-1/books/developers-handbook/tools/chapter.sgml +++ b/en_US.ISO8859-1/books/developers-handbook/tools/chapter.sgml @@ -1,2311 +1,2311 @@ James Raynard Written by Murray Stokely Modifications for the Developer's Handbook by Programming Tools Synopsis This chapter is an introduction to using some of the programming tools supplied with FreeBSD, although much of it will be applicable to many other versions of Unix. It does not attempt to describe coding in any detail. Most of the chapter assumes little or no previous programming knowledge, although it is hoped that most programmers will find something of value in it. Introduction FreeBSD offers an excellent development environment. Compilers for C, C++, and Fortran and an assembler come with the basic system, not to mention a Perl interpreter and classic Unix tools such as sed and awk. If that is not enough, there are many more compilers and interpreters in the Ports collection. FreeBSD is very compatible with standards such as POSIX and ANSI C, as well with its own BSD heritage, so it is possible to write applications that will compile and run with little or no modification on a wide range of platforms. However, all this power can be rather overwhelming at first if you have never written programs on a Unix platform before. This document aims to help you get up and running, without getting too deeply into more advanced topics. The intention is that this document should give you enough of the basics to be able to make some sense of the documentation. Most of the document requires little or no knowledge of programming, although it does assume a basic competence with using Unix and a willingness to learn! Introduction to Programming A program is a set of instructions that tell the computer to do various things; sometimes the instruction it has to perform depends on what happened when it performed a previous instruction. This section gives an overview of the two main ways in which you can give these instructions, or commands as they are usually called. One way uses an interpreter, the other a compiler. As human languages are too difficult for a computer to understand in an unambiguous way, commands are usually written in one or other languages specially designed for the purpose. Interpreters With an interpreter, the language comes as an environment, where you type in commands at a prompt and the environment executes them for you. For more complicated programs, you can type the commands into a file and get the interpreter to load the file and execute the commands in it. If anything goes wrong, many interpreters will drop you into a debugger to help you track down the problem. The advantage of this is that you can see the results of your commands immediately, and mistakes can be corrected readily. The biggest disadvantage comes when you want to share your programs with someone. They must have the same interpreter, or you must have some way of giving it to them, and they need to understand how to use it. Also users may not appreciate being thrown into a debugger if they press the wrong key! From a performance point of view, interpreters can use up a lot of memory, and generally do not generate code as efficiently as compilers. In my opinion, interpreted languages are the best way to start if you have not done any programming before. This kind of environment is typically found with languages like Lisp, Smalltalk, Perl and Basic. It could also be argued that the Unix shell (sh, csh) is itself an interpreter, and many people do in fact write shell scripts to help with various housekeeping tasks on their machine. Indeed, part of the original Unix philosophy was to provide lots of small utility programs that could be linked together in shell scripts to perform useful tasks. Interpreters available with FreeBSD Here is a list of interpreters that are available as FreeBSD packages, with a brief discussion of some of the more popular interpreted languages. To get one of these packages, all you need to do is to click on the hotlink for the package, then run &prompt.root; pkg_add package name as root. Obviously, you will need to have a fully functional FreeBSD 2.1.0 or later system for the package to work! BASIC Short for Beginner's All-purpose Symbolic Instruction Code. Developed in the 1950s for teaching University students to program and provided with every self-respecting personal computer in the 1980s, BASIC has been the first programming language for many programmers. It is also the foundation for Visual Basic. The Bywater Basic Interpreter and the Phil Cockroft's Basic Interpreter (formerly Rabbit Basic) are available as FreeBSD packages. Lisp A language that was developed in the late 1950s as an alternative to the number-crunching languages that were popular at the time. Instead of being based on numbers, Lisp is based on lists; in fact the name is short for List Processing. Very popular in AI (Artificial Intelligence) circles. Lisp is an extremely powerful and sophisticated language, but can be rather large and unwieldy. FreeBSD has GNU Common Lisp available as a package. Perl Very popular with system administrators for writing scripts; also often used on World Wide Web servers for writing CGI scripts. Perl is installed as /usr/bin/perl in the FreeBSD base system. Scheme A dialect of Lisp that is rather more compact and cleaner than Common Lisp. Popular in Universities as it is simple enough to teach to undergraduates as a first language, while it has a high enough level of abstraction to be used in research work. FreeBSD has packages of the Elk Scheme Interpreter, the MIT Scheme Interpreter and the SCM Scheme Interpreter. Icon The Icon Programming Language. Logo Brian Harvey's LOGO Interpreter. Python The Python Object-Oriented Programming Language Compilers Compilers are rather different. First of all, you write your code in a file (or files) using an editor. You then run the compiler and see if it accepts your program. If it did not compile, grit your teeth and go back to the editor; if it did compile and gave you a program, you can run it either at a shell command prompt or in a debugger to see if it works properly. If you run it in the shell, you may get a core dump. Obviously, this is not quite as direct as using an interpreter. However it allows you to do a lot of things which are very difficult or even impossible with an interpreter, such as writing code which interacts closely with the operating system—or even writing your own operating system! It is also useful if you need to write very efficient code, as the compiler can take its time and optimise the code, which would not be acceptable in an interpreter. And distributing a program written for a compiler is usually more straightforward than one written for an interpreter—you can just give them a copy of the executable, assuming they have the same operating system as you. Compiled languages include Pascal, C and C++. C and C++ are rather unforgiving languages, and best suited to more experienced programmers; Pascal, on the other hand, was designed as an educational language, and is quite a good language to start with. FreeBSD does not include Pascal support in the base system, but the GNU Pascal Compiler (gpc) is available in the ports collection. As the edit-compile-run-debug cycle is rather tedious when using separate programs, many commercial compiler makers have produced Integrated Development Environments (IDEs for short). FreeBSD does not include an IDE in the base system, but devel/kdevelop is available in the ports tree and many use Emacs for this purpose. Using Emacs as an IDE is discussed in . Compiling with <command>cc</command> This section deals only with the GNU compiler for C and C++, since that comes with the base FreeBSD system. It can be invoked by either cc or gcc. The details of producing a program with an interpreter vary considerably between interpreters, and are usually well covered in the documentation and on-line help for the interpreter. Once you have written your masterpiece, the next step is to convert it into something that will (hopefully!) run on FreeBSD. This usually involves several steps, each of which is done by a separate program. Pre-process your source code to remove comments and do other tricks like expanding macros in C. Check the syntax of your code to see if you have obeyed the rules of the language. If you have not, it will complain! Convert the source code into assembly language—this is very close to machine code, but still understandable by humans. Allegedly. To be strictly accurate, cc converts the source code into its own, machine-independent p-code instead of assembly language at this stage. Convert the assembly language into machine code—yep, we are talking bits and bytes, ones and zeros here. Check that you have used things like functions and global variables in a consistent way. For example, if you have called a non-existent function, it will complain. If you are trying to produce an executable from several source code files, work out how to fit them all together. Work out how to produce something that the system's run-time loader will be able to load into memory and run. - Finally, write the executable on the file system. + Finally, write the executable on the filesystem. The word compiling is often used to refer to just steps 1 to 4—the others are referred to as linking. Sometimes step 1 is referred to as pre-processing and steps 3-4 as assembling. Fortunately, almost all this detail is hidden from you, as cc is a front end that manages calling all these programs with the right arguments for you; simply typing &prompt.user; cc foobar.c will cause foobar.c to be compiled by all the steps above. If you have more than one file to compile, just do something like &prompt.user; cc foo.c bar.c Note that the syntax checking is just that—checking the syntax. It will not check for any logical mistakes you may have made, like putting the program into an infinite loop, or using a bubble sort when you meant to use a binary sort. In case you did not know, a binary sort is an efficient way of sorting things into order and a bubble sort is not. There are lots and lots of options for cc, which are all in the manual page. Here are a few of the most important ones, with examples of how to use them. The output name of the file. If you do not use this option, cc will produce an executable called a.out. The reasons for this are buried in the mists of history. &prompt.user; cc foobar.c executable is a.out &prompt.user; cc -o foobar foobar.c executable is foobar Just compile the file, do not link it. Useful for toy programs where you just want to check the syntax, or if you are using a Makefile. &prompt.user; cc -c foobar.c This will produce an object file (not an executable) called foobar.o. This can be linked together with other object files into an executable. Create a debug version of the executable. This makes the compiler put information into the executable about which line of which source file corresponds to which function call. A debugger can use this information to show the source code as you step through the program, which is very useful; the disadvantage is that all this extra information makes the program much bigger. Normally, you compile with while you are developing a program and then compile a release version without when you are satisfied it works properly. &prompt.user; cc -g foobar.c This will produce a debug version of the program. Note, we did not use the flag to specify the executable name, so we will get an executable called a.out. Producing a debug version called foobar is left as an exercise for the reader! Create an optimised version of the executable. The compiler performs various clever tricks to try and produce an executable that runs faster than normal. You can add a number after the to specify a higher level of optimisation, but this often exposes bugs in the compiler's optimiser. For instance, the version of cc that comes with the 2.1.0 release of FreeBSD is known to produce bad code with the option in some circumstances. Optimisation is usually only turned on when compiling a release version. &prompt.user; cc -O -o foobar foobar.c This will produce an optimised version of foobar. The following three flags will force cc to check that your code complies to the relevant international standard, often referred to as the ANSI standard, though strictly speaking it is an ISO standard. Enable all the warnings which the authors of cc believe are worthwhile. Despite the name, it will not enable all the warnings cc is capable of. Turn off most, but not all, of the non-ANSI C features provided by cc. Despite the name, it does not guarantee strictly that your code will comply to the standard. Turn off all cc's non-ANSI C features. Without these flags, cc will allow you to use some of its non-standard extensions to the standard. Some of these are very useful, but will not work with other compilers—in fact, one of the main aims of the standard is to allow people to write code that will work with any compiler on any system. This is known as portable code. Generally, you should try to make your code as portable as possible, as otherwise you may have to completely rewrite the program later to get it to work somewhere else—and who knows what you may be using in a few years time? &prompt.user; cc -Wall -ansi -pedantic -o foobar foobar.c This will produce an executable foobar after checking foobar.c for standard compliance. Specify a function library to be used during when linking. The most common example of this is when compiling a program that uses some of the mathematical functions in C. Unlike most other platforms, these are in a separate library from the standard C one and you have to tell the compiler to add it. The rule is that if the library is called libsomething.a, you give cc the argument . For example, the math library is libm.a, so you give cc the argument . A common gotcha with the math library is that it has to be the last library on the command line. &prompt.user; cc -o foobar foobar.c -lm This will link the math library functions into foobar. If you are compiling C++ code, you need to add , or if you are using FreeBSD 2.2 or later, to the command line argument to link the C++ library functions. Alternatively, you can run c++ instead of cc, which does this for you. c++ can also be invoked as g++ on FreeBSD. &prompt.user; cc -o foobar foobar.cc -lg++ For FreeBSD 2.1.6 and earlier &prompt.user; cc -o foobar foobar.cc -lstdc++ For FreeBSD 2.2 and later &prompt.user; c++ -o foobar foobar.cc Each of these will both produce an executable foobar from the C++ source file foobar.cc. Note that, on Unix systems, C++ source files traditionally end in .C, .cxx or .cc, rather than the MS-DOS style .cpp (which was already used for something else). gcc used to rely on this to work out what kind of compiler to use on the source file; however, this restriction no longer applies, so you may now call your C++ files .cpp with impunity! Common <command>cc</command> Queries and Problems I am trying to write a program which uses the sin() function and I get an error like this. What does it mean? /var/tmp/cc0143941.o: Undefined symbol `_sin' referenced from text segment When using mathematical functions like sin(), you have to tell cc to link in the math library, like so: &prompt.user; cc -o foobar foobar.c -lm All right, I wrote this simple program to practice using . All it does is raise 2.1 to the power of 6. #include <stdio.h> int main() { float f; f = pow(2.1, 6); printf("2.1 ^ 6 = %f\n", f); return 0; } and I compiled it as: &prompt.user; cc temp.c -lm like you said I should, but I get this when I run it: &prompt.user; ./a.out 2.1 ^ 6 = 1023.000000 This is not the right answer! What is going on? When the compiler sees you call a function, it checks if it has already seen a prototype for it. If it has not, it assumes the function returns an int, which is definitely not what you want here. So how do I fix this? The prototypes for the mathematical functions are in math.h. If you include this file, the compiler will be able to find the prototype and it will stop doing strange things to your calculation! #include <math.h> #include <stdio.h> int main() { ... After recompiling it as you did before, run it: &prompt.user; ./a.out 2.1 ^ 6 = 85.766121 If you are using any of the mathematical functions, always include math.h and remember to link in the math library. I compiled a file called foobar.c and I cannot find an executable called foobar. Where's it gone? Remember, cc will call the executable a.out unless you tell it differently. Use the option: &prompt.user; cc -o foobar foobar.c OK, I have an executable called foobar, I can see it when I run ls, but when I type in foobar at the command prompt it tells me there is no such file. Why can it not find it? Unlike MS-DOS, Unix does not look in the current directory when it is trying to find out which executable you want it to run, unless you tell it to. Either type ./foobar, which means run the file called foobar in the current directory, or change your PATH environment variable so that it looks something like bin:/usr/bin:/usr/local/bin:. The dot at the end means look in the current directory if it is not in any of the others. I called my executable test, but nothing happens when I run it. What is going on? Most Unix systems have a program called test in /usr/bin and the shell is picking that one up before it gets to checking the current directory. Either type: &prompt.user; ./test or choose a better name for your program! I compiled my program and it seemed to run all right at first, then there was an error and it said something about core dumped. What does that mean? The name core dump dates back to the very early days of Unix, when the machines used core memory for storing data. Basically, if the program failed under certain conditions, the system would write the contents of core memory to disk in a file called core, which the programmer could then pore over to find out what went wrong. Fascinating stuff, but what I am supposed to do now? Use gdb to analyse the core (see ). When my program dumped core, it said something about a segmentation fault. What is that? This basically means that your program tried to perform some sort of illegal operation on memory; Unix is designed to protect the operating system and other programs from rogue programs. Common causes for this are: Trying to write to a NULL pointer, eg char *foo = NULL; strcpy(foo, "bang!"); Using a pointer that has not been initialised, eg char *foo; strcpy(foo, "bang!"); The pointer will have some random value that, with luck, will point into an area of memory that is not available to your program and the kernel will kill your program before it can do any damage. If you are unlucky, it will point somewhere inside your own program and corrupt one of your data structures, causing the program to fail mysteriously. Trying to access past the end of an array, eg int bar[20]; bar[27] = 6; Trying to store something in read-only memory, eg char *foo = "My string"; strcpy(foo, "bang!"); Unix compilers often put string literals like "My string" into read-only areas of memory. Doing naughty things with malloc() and free(), eg char bar[80]; free(bar); or char *foo = malloc(27); free(foo); free(foo); Making one of these mistakes will not always lead to an error, but they are always bad practice. Some systems and compilers are more tolerant than others, which is why programs that ran well on one system can crash when you try them on an another. Sometimes when I get a core dump it says bus error. It says in my Unix book that this means a hardware problem, but the computer still seems to be working. Is this true? No, fortunately not (unless of course you really do have a hardware problem…). This is usually another way of saying that you accessed memory in a way you should not have. This dumping core business sounds as though it could be quite useful, if I can make it happen when I want to. Can I do this, or do I have to wait until there is an error? Yes, just go to another console or xterm, do &prompt.user; ps to find out the process ID of your program, and do &prompt.user; kill -ABRT pid where pid is the process ID you looked up. This is useful if your program has got stuck in an infinite loop, for instance. If your program happens to trap SIGABRT, there are several other signals which have a similar effect. Alternatively, you can create a core dump from inside your program, by calling the abort() function. See the man page of &man.abort.3; to learn more. If you want to create a core dump from outside your program, but do not want the process to terminate, you can use the gcore program. See the man page of &man.gcore.1; for more information. Make What is <command>make</command>? When you are working on a simple program with only one or two source files, typing in &prompt.user; cc file1.c file2.c is not too bad, but it quickly becomes very tedious when there are several files—and it can take a while to compile, too. One way to get around this is to use object files and only recompile the source file if the source code has changed. So we could have something like: &prompt.user; cc file1.o file2.o … file37.c … if we had changed file37.c, but not any of the others, since the last time we compiled. This may speed up the compilation quite a bit, but does not solve the typing problem. Or we could write a shell script to solve the typing problem, but it would have to re-compile everything, making it very inefficient on a large project. What happens if we have hundreds of source files lying about? What if we are working in a team with other people who forget to tell us when they have changed one of their source files that we use? Perhaps we could put the two solutions together and write something like a shell script that would contain some kind of magic rule saying when a source file needs compiling. Now all we need now is a program that can understand these rules, as it is a bit too complicated for the shell. This program is called make. It reads in a file, called a makefile, that tells it how different files depend on each other, and works out which files need to be re-compiled and which ones do not. For example, a rule could say something like if fromboz.o is older than fromboz.c, that means someone must have changed fromboz.c, so it needs to be re-compiled. The makefile also has rules telling make how to re-compile the source file, making it a much more powerful tool. Makefiles are typically kept in the same directory as the source they apply to, and can be called makefile, Makefile or MAKEFILE. Most programmers use the name Makefile, as this puts it near the top of a directory listing, where it can easily be seen. They do not use the MAKEFILE form as block capitals are often used for documentation files like README. Example of using <command>make</command> Here is a very simple make file: foo: foo.c cc -o foo foo.c It consists of two lines, a dependency line and a creation line. The dependency line here consists of the name of the program (known as the target), followed by a colon, then whitespace, then the name of the source file. When make reads this line, it looks to see if foo exists; if it exists, it compares the time foo was last modified to the time foo.c was last modified. If foo does not exist, or is older than foo.c, it then looks at the creation line to find out what to do. In other words, this is the rule for working out when foo.c needs to be re-compiled. The creation line starts with a tab (press the tab key) and then the command you would type to create foo if you were doing it at a command prompt. If foo is out of date, or does not exist, make then executes this command to create it. In other words, this is the rule which tells make how to re-compile foo.c. So, when you type make, it will make sure that foo is up to date with respect to your latest changes to foo.c. This principle can be extended to Makefiles with hundreds of targets—in fact, on FreeBSD, it is possible to compile the entire operating system just by typing make world in the appropriate directory! Another useful property of makefiles is that the targets do not have to be programs. For instance, we could have a make file that looks like this: foo: foo.c cc -o foo foo.c install: cp foo /home/me We can tell make which target we want to make by typing: &prompt.user; make target make will then only look at that target and ignore any others. For example, if we type make foo with the makefile above, make will ignore the install target. If we just type make on its own, make will always look at the first target and then stop without looking at any others. So if we typed make here, it will just go to the foo target, re-compile foo if necessary, and then stop without going on to the install target. Notice that the install target does not actually depend on anything! This means that the command on the following line is always executed when we try to make that target by typing make install. In this case, it will copy foo into the user's home directory. This is often used by application makefiles, so that the application can be installed in the correct directory when it has been correctly compiled. This is a slightly confusing subject to try to explain. If you do not quite understand how make works, the best thing to do is to write a simple program like hello world and a make file like the one above and experiment. Then progress to using more than one source file, or having the source file include a header file. The touch command is very useful here—it changes the date on a file without you having to edit it. Make and include-files C code often starts with a list of files to include, for example stdio.h. Some of these files are system-include files, some of them are from the project you are now working on: #include <stdio.h> #include "foo.h" int main(.... To make sure that this file is recompiled the moment foo.h is changed, you have to add it in your Makefile: foo: foo.c foo.h The moment your project is getting bigger and you have more and more own include-files to maintain, it will be a pain to keep track of all include files and the files which are depending on it. If you change an include-file but forget to recompile all the files which are depending on it, the results will be devastating. gcc has an option to analyze your files and to produce a list of include-files and their dependencies: . If you add this to your Makefile: depend: gcc -E -MM *.c > .depend and run make depend, the file .depend will appear with a list of object-files, C-files and the include-files: foo.o: foo.c foo.h If you change foo.h, next time you run make all files depending on foo.h will be recompiled. Do not forget to run make depend each time you add an include-file to one of your files. FreeBSD Makefiles Makefiles can be rather complicated to write. Fortunately, BSD-based systems like FreeBSD come with some very powerful ones as part of the system. One very good example of this is the FreeBSD ports system. Here is the essential part of a typical ports Makefile: MASTER_SITES= ftp://freefall.cdrom.com/pub/FreeBSD/LOCAL_PORTS/ DISTFILES= scheme-microcode+dist-7.3-freebsd.tgz .include <bsd.port.mk> Now, if we go to the directory for this port and type make, the following happens: A check is made to see if the source code for this port is already on the system. If it is not, an FTP connection to the URL in MASTER_SITES is set up to download the source. The checksum for the source is calculated and compared it with one for a known, good, copy of the source. This is to make sure that the source was not corrupted while in transit. Any changes required to make the source work on FreeBSD are applied—this is known as patching. Any special configuration needed for the source is done. (Many Unix program distributions try to work out which version of Unix they are being compiled on and which optional Unix features are present—this is where they are given the information in the FreeBSD ports scenario). The source code for the program is compiled. In effect, we change to the directory where the source was unpacked and do make—the program's own make file has the necessary information to build the program. We now have a compiled version of the program. If we wish, we can test it now; when we feel confident about the program, we can type make install. This will cause the program and any supporting files it needs to be copied into the correct location; an entry is also made into a package database, so that the port can easily be uninstalled later if we change our mind about it. Now I think you will agree that is rather impressive for a four line script! The secret lies in the last line, which tells make to look in the system makefile called bsd.port.mk. It is easy to overlook this line, but this is where all the clever stuff comes from—someone has written a makefile that tells make to do all the things above (plus a couple of other things I did not mention, including handling any errors that may occur) and anyone can get access to that just by putting a single line in their own make file! If you want to have a look at these system makefiles, they are in /usr/share/mk, but it is probably best to wait until you have had a bit of practice with makefiles, as they are very complicated (and if you do look at them, make sure you have a flask of strong coffee handy!) More advanced uses of <command>make</command> Make is a very powerful tool, and can do much more than the simple example above shows. Unfortunately, there are several different versions of make, and they all differ considerably. The best way to learn what they can do is probably to read the documentation—hopefully this introduction will have given you a base from which you can do this. The version of make that comes with FreeBSD is the Berkeley make; there is a tutorial for it in /usr/share/doc/psd/12.make. To view it, do &prompt.user; zmore paper.ascii.gz in that directory. Many applications in the ports use GNU make, which has a very good set of info pages. If you have installed any of these ports, GNU make will automatically have been installed as gmake. It is also available as a port and package in its own right. To view the info pages for GNU make, you will have to edit the dir file in the /usr/local/info directory to add an entry for it. This involves adding a line like * Make: (make). The GNU Make utility. to the file. Once you have done this, you can type info and then select make from the menu (or in Emacs, do C-h i). Debugging The Debugger The debugger that comes with FreeBSD is called gdb (GNU debugger). You start it up by typing &prompt.user; gdb progname although most people prefer to run it inside Emacs. You can do this by: M-x gdb RET progname RET Using a debugger allows you to run the program under more controlled circumstances. Typically, you can step through the program a line at a time, inspect the value of variables, change them, tell the debugger to run up to a certain point and then stop, and so on. You can even attach to a program that is already running, or load a core file to investigate why the program crashed. It is even possible to debug the kernel, though that is a little trickier than the user applications we will be discussing in this section. gdb has quite good on-line help, as well as a set of info pages, so this section will concentrate on a few of the basic commands. Finally, if you find its text-based command-prompt style off-putting, there is a graphical front-end for it (xxgdb) in the ports collection. This section is intended to be an introduction to using gdb and does not cover specialised topics such as debugging the kernel. Running a program in the debugger You will need to have compiled the program with the option to get the most out of using gdb. It will work without, but you will only see the name of the function you are in, instead of the source code. If you see a line like: … (no debugging symbols found) … when gdb starts up, you will know that the program was not compiled with the option. At the gdb prompt, type break main. This will tell the debugger to skip over the preliminary set-up code in the program and start at the beginning of your code. Now type run to start the program—it will start at the beginning of the set-up code and then get stopped by the debugger when it calls main(). (If you have ever wondered where main() gets called from, now you know!). You can now step through the program, a line at a time, by pressing n. If you get to a function call, you can step into it by pressing s. Once you are in a function call, you can return from stepping into a function call by pressing f. You can also use up and down to take a quick look at the caller. Here is a simple example of how to spot a mistake in a program with gdb. This is our program (with a deliberate mistake): #include <stdio.h> int bazz(int anint); main() { int i; printf("This is my program\n"); bazz(i); return 0; } int bazz(int anint) { printf("You gave me %d\n", anint); return anint; } This program sets i to be 5 and passes it to a function bazz() which prints out the number we gave it. When we compile and run the program we get &prompt.user; cc -g -o temp temp.c &prompt.user; ./temp This is my program anint = 4231 That was not what we expected! Time to see what is going on! &prompt.user; gdb temp GDB is free software and you are welcome to distribute copies of it under certain conditions; type "show copying" to see the conditions. There is absolutely no warranty for GDB; type "show warranty" for details. GDB 4.13 (i386-unknown-freebsd), Copyright 1994 Free Software Foundation, Inc. (gdb) break main Skip the set-up code Breakpoint 1 at 0x160f: file temp.c, line 9. gdb puts breakpoint at main() (gdb) run Run as far as main() Starting program: /home/james/tmp/temp Program starts running Breakpoint 1, main () at temp.c:9 gdb stops at main() (gdb) n Go to next line This is my program Program prints out (gdb) s step into bazz() bazz (anint=4231) at temp.c:17 gdb displays stack frame (gdb) Hang on a minute! How did anint get to be 4231? Did we not we set it to be 5 in main()? Let's move up to main() and have a look. (gdb) up Move up call stack #1 0x1625 in main () at temp.c:11 gdb displays stack frame (gdb) p i Show us the value of i $1 = 4231 gdb displays 4231 Oh dear! Looking at the code, we forgot to initialise i. We meant to put … main() { int i; i = 5; printf("This is my program\n"); … but we left the i=5; line out. As we did not initialise i, it had whatever number happened to be in that area of memory when the program ran, which in this case happened to be 4231. gdb displays the stack frame every time we go into or out of a function, even if we are using up and down to move around the call stack. This shows the name of the function and the values of its arguments, which helps us keep track of where we are and what is going on. (The stack is a storage area where the program stores information about the arguments passed to functions and where to go when it returns from a function call). Examining a core file A core file is basically a file which contains the complete state of the process when it crashed. In the good old days, programmers had to print out hex listings of core files and sweat over machine code manuals, but now life is a bit easier. Incidentally, under FreeBSD and other 4.4BSD systems, a core file is called progname.core instead of just core, to make it clearer which program a core file belongs to. To examine a core file, start up gdb in the usual way. Instead of typing break or run, type (gdb) core progname.core If you are not in the same directory as the core file, you will have to do dir /path/to/core/file first. You should see something like this: &prompt.user; gdb a.out GDB is free software and you are welcome to distribute copies of it under certain conditions; type "show copying" to see the conditions. There is absolutely no warranty for GDB; type "show warranty" for details. GDB 4.13 (i386-unknown-freebsd), Copyright 1994 Free Software Foundation, Inc. (gdb) core a.out.core Core was generated by `a.out'. Program terminated with signal 11, Segmentation fault. Cannot access memory at address 0x7020796d. #0 0x164a in bazz (anint=0x5) at temp.c:17 (gdb) In this case, the program was called a.out, so the core file is called a.out.core. We can see that the program crashed due to trying to access an area in memory that was not available to it in a function called bazz. Sometimes it is useful to be able to see how a function was called, as the problem could have occurred a long way up the call stack in a complex program. The bt command causes gdb to print out a back-trace of the call stack: (gdb) bt #0 0x164a in bazz (anint=0x5) at temp.c:17 #1 0xefbfd888 in end () #2 0x162c in main () at temp.c:11 (gdb) The end() function is called when a program crashes; in this case, the bazz() function was called from main(). Attaching to a running program One of the neatest features about gdb is that it can attach to a program that is already running. Of course, that assumes you have sufficient permissions to do so. A common problem is when you are stepping through a program that forks, and you want to trace the child, but the debugger will only let you trace the parent. What you do is start up another gdb, use ps to find the process ID for the child, and do (gdb) attach pid in gdb, and then debug as usual. That is all very well, you are probably thinking, but by the time I have done that, the child process will be over the hill and far away. Fear not, gentle reader, here is how to do it (courtesy of the gdb info pages): … if ((pid = fork()) < 0) /* _Always_ check this */ error(); else if (pid == 0) { /* child */ int PauseMode = 1; while (PauseMode) sleep(10); /* Wait until someone attaches to us */ … } else { /* parent */ … Now all you have to do is attach to the child, set PauseMode to 0, and wait for the sleep() call to return! Using Emacs as a Development Environment Emacs Unfortunately, Unix systems do not come with the kind of everything-you-ever-wanted-and-lots-more-you-did-not-in-one-gigantic-package integrated development environments that other systems have. Some powerful, free IDEs now exist, such as KDevelop in the ports collection. However, it is possible to set up your own environment. It may not be as pretty, and it may not be quite as integrated, but you can set it up the way you want it. And it is free. And you have the source to it. The key to it all is Emacs. Now there are some people who loathe it, but many who love it. If you are one of the former, I am afraid this section will hold little of interest to you. Also, you will need a fair amount of memory to run it—I would recommend 8MB in text mode and 16MB in X as the bare minimum to get reasonable performance. Emacs is basically a highly customisable editor—indeed, it has been customised to the point where it is more like an operating system than an editor! Many developers and sysadmins do in fact spend practically all their time working inside Emacs, leaving it only to log out. It is impossible even to summarise everything Emacs can do here, but here are some of the features of interest to developers: Very powerful editor, allowing search-and-replace on both strings and regular expressions (patterns), jumping to start/end of block expression, etc, etc. Pull-down menus and online help. Language-dependent syntax highlighting and indentation. Completely customisable. You can compile and debug programs within Emacs. On a compilation error, you can jump to the offending line of source code. Friendly-ish front-end to the info program used for reading GNU hypertext documentation, including the documentation on Emacs itself. Friendly front-end to gdb, allowing you to look at the source code as you step through your program. You can read Usenet news and mail while your program is compiling. And doubtless many more that I have overlooked. Emacs can be installed on FreeBSD using the Emacs port. Once it is installed, start it up and do C-h t to read an Emacs tutorial—that means hold down the control key, press h, let go of the control key, and then press t. (Alternatively, you can you use the mouse to select Emacs Tutorial from the Help menu). Although Emacs does have menus, it is well worth learning the key bindings, as it is much quicker when you are editing something to press a couple of keys than to try and find the mouse and then click on the right place. And, when you are talking to seasoned Emacs users, you will find they often casually throw around expressions like M-x replace-s RET foo RET bar RET so it is useful to know what they mean. And in any case, Emacs has far too many useful functions for them to all fit on the menu bars. Fortunately, it is quite easy to pick up the key-bindings, as they are displayed next to the menu item. My advice is to use the menu item for, say, opening a file until you understand how it works and feel confident with it, then try doing C-x C-f. When you are happy with that, move on to another menu command. If you can not remember what a particular combination of keys does, select Describe Key from the Help menu and type it in—Emacs will tell you what it does. You can also use the Command Apropos menu item to find out all the commands which contain a particular word in them, with the key binding next to it. By the way, the expression above means hold down the Meta key, press x, release the Meta key, type replace-s (short for replace-string—another feature of Emacs is that you can abbreviate commands), press the return key, type foo (the string you want replaced), press the return key, type bar (the string you want to replace foo with) and press return again. Emacs will then do the search-and-replace operation you have just requested. If you are wondering what on earth the Meta key is, it is a special key that many Unix workstations have. Unfortunately, PC's do not have one, so it is usually the alt key (or if you are unlucky, the escape key). Oh, and to get out of Emacs, do C-x C-c (that means hold down the control key, press x, press c and release the control key). If you have any unsaved files open, Emacs will ask you if you want to save them. (Ignore the bit in the documentation where it says C-z is the usual way to leave Emacs—that leaves Emacs hanging around in the background, and is only really useful if you are on a system which does not have virtual terminals). Configuring Emacs Emacs does many wonderful things; some of them are built in, some of them need to be configured. Instead of using a proprietary macro language for configuration, Emacs uses a version of Lisp specially adapted for editors, known as Emacs Lisp. This can be quite useful if you want to go on and learn something like Common Lisp, as it is considerably smaller than Common Lisp (although still quite big!). The best way to learn Emacs Lisp is to download the Emacs Tutorial However, there is no need to actually know any Lisp to get started with configuring Emacs, as I have included a sample .emacs file, which should be enough to get you started. Just copy it into your home directory and restart Emacs if it is already running; it will read the commands from the file and (hopefully) give you a useful basic setup. A sample <filename>.emacs</filename> file Unfortunately, there is far too much here to explain it in detail; however there are one or two points worth mentioning. Everything beginning with a ; is a comment and is ignored by Emacs. In the first line, the -*- Emacs-Lisp -*- is so that we can edit the .emacs file itself within Emacs and get all the fancy features for editing Emacs Lisp. Emacs usually tries to guess this based on the filename, and may not get it right for .emacs. The tab key is bound to an indentation function in some modes, so when you press the tab key, it will indent the current line of code. If you want to put a tab character in whatever you are writing, hold the control key down while you are pressing the tab key. This file supports syntax highlighting for C, C++, Perl, Lisp and Scheme, by guessing the language from the filename. Emacs already has a pre-defined function called next-error. In a compilation output window, this allows you to move from one compilation error to the next by doing M-n; we define a complementary function, previous-error, that allows you to go to a previous error by doing M-p. The nicest feature of all is that C-c C-c will open up the source file in which the error occurred and jump to the appropriate line. We enable Emacs's ability to act as a server, so that if you are doing something outside Emacs and you want to edit a file, you can just type in &prompt.user; emacsclient filename and then you can edit the file in your Emacs! Many Emacs users set their EDITOR environment to emacsclient so this happens every time they need to edit a file. A sample <filename>.emacs</filename> file ;; -*-Emacs-Lisp-*- ;; This file is designed to be re-evaled; use the variable first-time ;; to avoid any problems with this. (defvar first-time t "Flag signifying this is the first time that .emacs has been evaled") ;; Meta (global-set-key "\M- " 'set-mark-command) (global-set-key "\M-\C-h" 'backward-kill-word) (global-set-key "\M-\C-r" 'query-replace) (global-set-key "\M-r" 'replace-string) (global-set-key "\M-g" 'goto-line) (global-set-key "\M-h" 'help-command) ;; Function keys (global-set-key [f1] 'manual-entry) (global-set-key [f2] 'info) (global-set-key [f3] 'repeat-complex-command) (global-set-key [f4] 'advertised-undo) (global-set-key [f5] 'eval-current-buffer) (global-set-key [f6] 'buffer-menu) (global-set-key [f7] 'other-window) (global-set-key [f8] 'find-file) (global-set-key [f9] 'save-buffer) (global-set-key [f10] 'next-error) (global-set-key [f11] 'compile) (global-set-key [f12] 'grep) (global-set-key [C-f1] 'compile) (global-set-key [C-f2] 'grep) (global-set-key [C-f3] 'next-error) (global-set-key [C-f4] 'previous-error) (global-set-key [C-f5] 'display-faces) (global-set-key [C-f8] 'dired) (global-set-key [C-f10] 'kill-compilation) ;; Keypad bindings (global-set-key [up] "\C-p") (global-set-key [down] "\C-n") (global-set-key [left] "\C-b") (global-set-key [right] "\C-f") (global-set-key [home] "\C-a") (global-set-key [end] "\C-e") (global-set-key [prior] "\M-v") (global-set-key [next] "\C-v") (global-set-key [C-up] "\M-\C-b") (global-set-key [C-down] "\M-\C-f") (global-set-key [C-left] "\M-b") (global-set-key [C-right] "\M-f") (global-set-key [C-home] "\M-<") (global-set-key [C-end] "\M->") (global-set-key [C-prior] "\M-<") (global-set-key [C-next] "\M->") ;; Mouse (global-set-key [mouse-3] 'imenu) ;; Misc (global-set-key [C-tab] "\C-q\t") ; Control tab quotes a tab. (setq backup-by-copying-when-mismatch t) ;; Treat 'y' or <CR> as yes, 'n' as no. (fset 'yes-or-no-p 'y-or-n-p) (define-key query-replace-map [return] 'act) (define-key query-replace-map [?\C-m] 'act) ;; Load packages (require 'desktop) (require 'tar-mode) ;; Pretty diff mode (autoload 'ediff-buffers "ediff" "Intelligent Emacs interface to diff" t) (autoload 'ediff-files "ediff" "Intelligent Emacs interface to diff" t) (autoload 'ediff-files-remote "ediff" "Intelligent Emacs interface to diff") (if first-time (setq auto-mode-alist (append '(("\\.cpp$" . c++-mode) ("\\.hpp$" . c++-mode) ("\\.lsp$" . lisp-mode) ("\\.scm$" . scheme-mode) ("\\.pl$" . perl-mode) ) auto-mode-alist))) ;; Auto font lock mode (defvar font-lock-auto-mode-list (list 'c-mode 'c++-mode 'c++-c-mode 'emacs-lisp-mode 'lisp-mode 'perl-mode 'scheme-mode) "List of modes to always start in font-lock-mode") (defvar font-lock-mode-keyword-alist '((c++-c-mode . c-font-lock-keywords) (perl-mode . perl-font-lock-keywords)) "Associations between modes and keywords") (defun font-lock-auto-mode-select () "Automatically select font-lock-mode if the current major mode is in font-lock-auto-mode-list" (if (memq major-mode font-lock-auto-mode-list) (progn (font-lock-mode t)) ) ) (global-set-key [M-f1] 'font-lock-fontify-buffer) ;; New dabbrev stuff ;(require 'new-dabbrev) (setq dabbrev-always-check-other-buffers t) (setq dabbrev-abbrev-char-regexp "\\sw\\|\\s_") (add-hook 'emacs-lisp-mode-hook '(lambda () (set (make-local-variable 'dabbrev-case-fold-search) nil) (set (make-local-variable 'dabbrev-case-replace) nil))) (add-hook 'c-mode-hook '(lambda () (set (make-local-variable 'dabbrev-case-fold-search) nil) (set (make-local-variable 'dabbrev-case-replace) nil))) (add-hook 'text-mode-hook '(lambda () (set (make-local-variable 'dabbrev-case-fold-search) t) (set (make-local-variable 'dabbrev-case-replace) t))) ;; C++ and C mode... (defun my-c++-mode-hook () (setq tab-width 4) (define-key c++-mode-map "\C-m" 'reindent-then-newline-and-indent) (define-key c++-mode-map "\C-ce" 'c-comment-edit) (setq c++-auto-hungry-initial-state 'none) (setq c++-delete-function 'backward-delete-char) (setq c++-tab-always-indent t) (setq c-indent-level 4) (setq c-continued-statement-offset 4) (setq c++-empty-arglist-indent 4)) (defun my-c-mode-hook () (setq tab-width 4) (define-key c-mode-map "\C-m" 'reindent-then-newline-and-indent) (define-key c-mode-map "\C-ce" 'c-comment-edit) (setq c-auto-hungry-initial-state 'none) (setq c-delete-function 'backward-delete-char) (setq c-tab-always-indent t) ;; BSD-ish indentation style (setq c-indent-level 4) (setq c-continued-statement-offset 4) (setq c-brace-offset -4) (setq c-argdecl-indent 0) (setq c-label-offset -4)) ;; Perl mode (defun my-perl-mode-hook () (setq tab-width 4) (define-key c++-mode-map "\C-m" 'reindent-then-newline-and-indent) (setq perl-indent-level 4) (setq perl-continued-statement-offset 4)) ;; Scheme mode... (defun my-scheme-mode-hook () (define-key scheme-mode-map "\C-m" 'reindent-then-newline-and-indent)) ;; Emacs-Lisp mode... (defun my-lisp-mode-hook () (define-key lisp-mode-map "\C-m" 'reindent-then-newline-and-indent) (define-key lisp-mode-map "\C-i" 'lisp-indent-line) (define-key lisp-mode-map "\C-j" 'eval-print-last-sexp)) ;; Add all of the hooks... (add-hook 'c++-mode-hook 'my-c++-mode-hook) (add-hook 'c-mode-hook 'my-c-mode-hook) (add-hook 'scheme-mode-hook 'my-scheme-mode-hook) (add-hook 'emacs-lisp-mode-hook 'my-lisp-mode-hook) (add-hook 'lisp-mode-hook 'my-lisp-mode-hook) (add-hook 'perl-mode-hook 'my-perl-mode-hook) ;; Complement to next-error (defun previous-error (n) "Visit previous compilation error message and corresponding source code." (interactive "p") (next-error (- n))) ;; Misc... (transient-mark-mode 1) (setq mark-even-if-inactive t) (setq visible-bell nil) (setq next-line-add-newlines nil) (setq compile-command "make") (setq suggest-key-bindings nil) (put 'eval-expression 'disabled nil) (put 'narrow-to-region 'disabled nil) (put 'set-goal-column 'disabled nil) ;; Elisp archive searching (autoload 'format-lisp-code-directory "lispdir" nil t) (autoload 'lisp-dir-apropos "lispdir" nil t) (autoload 'lisp-dir-retrieve "lispdir" nil t) (autoload 'lisp-dir-verify "lispdir" nil t) ;; Font lock mode (defun my-make-face (face colour &optional bold) "Create a face from a colour and optionally make it bold" (make-face face) (copy-face 'default face) (set-face-foreground face colour) (if bold (make-face-bold face)) ) (if (eq window-system 'x) (progn (my-make-face 'blue "blue") (my-make-face 'red "red") (my-make-face 'green "dark green") (setq font-lock-comment-face 'blue) (setq font-lock-string-face 'bold) (setq font-lock-type-face 'bold) (setq font-lock-keyword-face 'bold) (setq font-lock-function-name-face 'red) (setq font-lock-doc-string-face 'green) (add-hook 'find-file-hooks 'font-lock-auto-mode-select) (setq baud-rate 1000000) (global-set-key "\C-cmm" 'menu-bar-mode) (global-set-key "\C-cms" 'scroll-bar-mode) (global-set-key [backspace] 'backward-delete-char) ; (global-set-key [delete] 'delete-char) (standard-display-european t) (load-library "iso-transl"))) ;; X11 or PC using direct screen writes (if window-system (progn ;; (global-set-key [M-f1] 'hilit-repaint-command) ;; (global-set-key [M-f2] [?\C-u M-f1]) (setq hilit-mode-enable-list '(not text-mode c-mode c++-mode emacs-lisp-mode lisp-mode scheme-mode) hilit-auto-highlight nil hilit-auto-rehighlight 'visible hilit-inhibit-hooks nil hilit-inhibit-rebinding t) (require 'hilit19) (require 'paren)) (setq baud-rate 2400) ; For slow serial connections ) ;; TTY type terminal (if (and (not window-system) (not (equal system-type 'ms-dos))) (progn (if first-time (progn (keyboard-translate ?\C-h ?\C-?) (keyboard-translate ?\C-? ?\C-h))))) ;; Under UNIX (if (not (equal system-type 'ms-dos)) (progn (if first-time (server-start)))) ;; Add any face changes here (add-hook 'term-setup-hook 'my-term-setup-hook) (defun my-term-setup-hook () (if (eq window-system 'pc) (progn ;; (set-face-background 'default "red") ))) ;; Restore the "desktop" - do this as late as possible (if first-time (progn (desktop-load-default) (desktop-read))) ;; Indicate that this file has been read at least once (setq first-time nil) ;; No need to debug anything now (setq debug-on-error nil) ;; All done (message "All done, %s%s" (user-login-name) ".") Extending the Range of Languages Emacs Understands Now, this is all very well if you only want to program in the languages already catered for in the .emacs file (C, C++, Perl, Lisp and Scheme), but what happens if a new language called whizbang comes out, full of exciting features? The first thing to do is find out if whizbang comes with any files that tell Emacs about the language. These usually end in .el, short for Emacs Lisp. For example, if whizbang is a FreeBSD port, we can locate these files by doing &prompt.user; find /usr/ports/lang/whizbang -name "*.el" -print and install them by copying them into the Emacs site Lisp directory. On FreeBSD 2.1.0-RELEASE, this is /usr/local/share/emacs/site-lisp. So for example, if the output from the find command was /usr/ports/lang/whizbang/work/misc/whizbang.el we would do &prompt.root; cp /usr/ports/lang/whizbang/work/misc/whizbang.el /usr/local/share/emacs/site-lisp Next, we need to decide what extension whizbang source files have. Let's say for the sake of argument that they all end in .wiz. We need to add an entry to our .emacs file to make sure Emacs will be able to use the information in whizbang.el. Find the auto-mode-alist entry in .emacs and add a line for whizbang, such as: … ("\\.lsp$" . lisp-mode) ("\\.wiz$" . whizbang-mode) ("\\.scm$" . scheme-mode) … This means that Emacs will automatically go into whizbang-mode when you edit a file ending in .wiz. Just below this, you will find the font-lock-auto-mode-list entry. Add whizbang-mode to it like so: ;; Auto font lock mode (defvar font-lock-auto-mode-list (list 'c-mode 'c++-mode 'c++-c-mode 'emacs-lisp-mode 'whizbang-mode 'lisp-mode 'perl-mode 'scheme-mode) "List of modes to always start in font-lock-mode") This means that Emacs will always enable font-lock-mode (ie syntax highlighting) when editing a .wiz file. And that is all that is needed. If there is anything else you want done automatically when you open up a .wiz file, you can add a whizbang-mode hook (see my-scheme-mode-hook for a simple example that adds auto-indent). Further Reading Brian Harvey and Matthew Wright Simply Scheme MIT 1994. ISBN 0-262-08226-8 Randall Schwartz Learning Perl O'Reilly 1993 ISBN 1-56592-042-2 Patrick Henry Winston and Berthold Klaus Paul Horn Lisp (3rd Edition) Addison-Wesley 1989 ISBN 0-201-08319-1 Brian W. Kernighan and Rob Pike The Unix Programming Environment Prentice-Hall 1984 ISBN 0-13-937681-X Brian W. Kernighan and Dennis M. Ritchie The C Programming Language (2nd Edition) Prentice-Hall 1988 ISBN 0-13-110362-8 Bjarne Stroustrup The C++ Programming Language Addison-Wesley 1991 ISBN 0-201-53992-6 W. Richard Stevens Advanced Programming in the Unix Environment Addison-Wesley 1992 ISBN 0-201-56317-7 W. Richard Stevens Unix Network Programming Prentice-Hall 1990 ISBN 0-13-949876-1 diff --git a/en_US.ISO8859-1/books/faq/book.sgml b/en_US.ISO8859-1/books/faq/book.sgml index 21f1ff8d7f..1b47903951 100644 --- a/en_US.ISO8859-1/books/faq/book.sgml +++ b/en_US.ISO8859-1/books/faq/book.sgml @@ -1,12475 +1,12475 @@ %man; %freebsd; %authors; %teams; %bookinfo; %mailing-lists; ]> Frequently Asked Questions for FreeBSD 2.X, 3.X and 4.X The FreeBSD Documentation Project $FreeBSD$ 1995 1996 1997 1998 1999 2000 2001 2002 The FreeBSD Documentation Project &bookinfo.legalnotice; This is the FAQ for FreeBSD versions 2.X, 3.X, and 4.X. All entries are assumed to be relevant to FreeBSD 2.0.5 and later, unless otherwise noted. Any entries with a <XXX> are under construction. If you are interested in helping with this project, send email to the &a.doc;. The latest version of this document is always available from the FreeBSD World Wide Web server. It may also be downloaded as one large HTML file with HTTP or as plain text, postscript, PDF, etc. from the FreeBSD FTP server. You may also want to Search the FAQ. Introduction Welcome to the FreeBSD 2.X-4.X FAQ! As is usual with Usenet FAQs, this document aims to cover the most frequently asked questions concerning the FreeBSD operating system (and of course answer them!). Although originally intended to reduce bandwidth and avoid the same old questions being asked over and over again, FAQs have become recognized as valuable information resources. Every effort has been made to make this FAQ as informative as possible; if you have any suggestions as to how it may be improved, please feel free to mail them to the &a.faq;. What is FreeBSD? Briefly, FreeBSD is a UN*X-like operating system for the i386 and Alpha/AXP platforms based on U.C. Berkeley's 4.4BSD-Lite release, with some 4.4BSD-Lite2 enhancements. It is also based indirectly on William Jolitz's port of U.C. Berkeley's Net/2 to the i386, known as 386BSD, though very little of the 386BSD code remains. A fuller description of what FreeBSD is and how it can work for you may be found on the FreeBSD home page. FreeBSD is used by companies, Internet Service Providers, researchers, computer professionals, students and home users all over the world in their work, education and recreation. See some of them in the FreeBSD Gallery. For more detailed information on FreeBSD, please see the FreeBSD Handbook. What is the goal of the FreeBSD Project? The goal of the FreeBSD Project is to provide software that may be used for any purpose and without strings attached. Many of us have a significant investment in the code (and project) and would certainly not mind a little financial compensation now and then, but we are definitely not prepared to insist on it. We believe that our first and foremost mission is to provide code to any and all comers, and for whatever purpose, so that the code gets the widest possible use and provides the widest possible benefit. This is, we believe, one of the most fundamental goals of Free Software and one that we enthusiastically support. That code in our source tree which falls under the GNU General Public License (GPL) or GNU Library General Public License (LGPL) comes with slightly more strings attached, though at least on the side of enforced access rather than the usual opposite. Due to the additional complexities that can evolve in the commercial use of GPL software, we do, however, endeavor to replace such software with submissions under the more relaxed FreeBSD copyright whenever possible. Does the FreeBSD license have any restrictions? Yes. Those restrictions do not control how you use the code, merely how you treat the FreeBSD Project itself. If you have serious license concerns, read the actual license. For the simply curious, the license can be summarized like this. Do not claim that you wrote this. Do not sue us if it breaks. Can FreeBSD replace my current operating system? For most people, yes. But this question is not quite that cut-and-dried. Most people do not actually use an operating system. They use applications. The applications are what really use the operating system. FreeBSD is designed to provide a robust and full-featured environment for applications. It supports a wide variety of web browsers, office suites, email readers, graphics programs, programming environments, network servers, and just about everything else you might want. Most of these applications can be managed through the Ports Collection. If you need to use an application that is only available on one operating system, you simply cannot replace that operating system. Chances are there is a very similar application on FreeBSD, however. If you want a solid office or Internet server, a reliable workstation, or just the ability to do your job without interruptions, FreeBSD will almost certainly do everything you need. Many computer users across the world, including both novices and experienced UNIX administrators, use FreeBSD as their only desktop operating system. If you are migrating to FreeBSD from some other UNIX environment, you already know most of what you need to. If your background is in graphic-driven operating systems such as Windows and older versions of Mac OS, expect to invest additional time learning the UNIX way of doing things. This FAQ and the FreeBSD Handbook are excellent places to start. Why is it called FreeBSD? It may be used free of charge, even by commercial users. Full source for the operating system is freely available, and the minimum possible restrictions have been placed upon its use, distribution and incorporation into other work (commercial or non-commercial). Anyone who has an improvement or bug fix is free to submit their code and have it added to the source tree (subject to one or two obvious provisions). It is worth pointing out that the word free is being used in two ways here, one meaning at no cost, the other meaning you can do whatever you like. Apart from one or two things you cannot do with the FreeBSD code, for example pretending you wrote it, you really can do whatever you like with it. What is the latest version of FreeBSD? Version &rel.current; is the latest RELEASE version; it was released in &rel.current.date;. This is also the latest STABLE version. Briefly, -STABLE is aimed at the ISP, corporate user, or any user who wants stability and a low change count over the wizzy new features of the latest -CURRENT snapshot. Releases can come from either branch, but -CURRENT should only be used if you are prepared for its increased volatility (relative to -STABLE, that is). Releases are made every few months. While many people stay more up-to-date with the FreeBSD sources (see the questions on FreeBSD-CURRENT and FreeBSD-STABLE) than that, doing so is more of a commitment, as the sources are a moving target. What is FreeBSD-CURRENT? FreeBSD-CURRENT is the development version of the operating system, which will in due course become 5.0-RELEASE. As such, it is really only of interest to developers working on the system and die-hard hobbyists. See the relevant section in the handbook for details on running -CURRENT. If you are not familiar with the operating system or are not capable of identifying the difference between a real problem and a temporary problem, you should not use FreeBSD-CURRENT. This branch sometimes evolves quite quickly and can be un-buildable for a number of days at a time. People that use FreeBSD-CURRENT are expected to be able to analyze any problems and only report them if they are deemed to be mistakes rather than glitches. Questions such as make world produces some error about groups on the -CURRENT mailing list may be treated with contempt. Every day, snapshot releases are made based on the current state of the -CURRENT and -STABLE branches. Nowadays, distributions of the occasional snapshot are now being made available. The goals behind each snapshot release are: To test the latest version of the installation software. To give people who would like to run -CURRENT or -STABLE but who do not have the time or bandwidth to follow it on a day-to-day basis an easy way of bootstrapping it onto their systems. To preserve a fixed reference point for the code in question, just in case we break something really badly later. (Although CVS normally prevents anything horrible like this happening :) To ensure that any new features in need of testing have the greatest possible number of potential testers. No claims are made that any -CURRENT snapshot can be considered production quality for any purpose. If you want to run a stable and fully tested system, you will have to stick to full releases, or use the -STABLE snapshots. Snapshot releases are directly available from ftp://current.FreeBSD.org/pub/FreeBSD/ for 5.0-CURRENT and releng4.FreeBSD.org for 4-STABLE snapshots. 3-STABLE snapshots are not being produced at the time of this writing (May 2000). Snapshots are generated, on the average, once a day for all actively developed branches. What is the FreeBSD-STABLE concept? Back when FreeBSD 2.0.5 was released, we decided to branch FreeBSD development into two parts. One branch was named -STABLE, with the intention that only well-tested bug fixes and small incremental enhancements would be made to it (for Internet Service Providers and other commercial enterprises for whom sudden shifts or experimental features are quite undesirable). The other branch was -CURRENT, which essentially has been one unbroken line leading towards 5.0-RELEASE (and beyond) since 2.0 was released. If a little ASCII art would help, this is how it looks: 2.0 | | | [2.1-STABLE] *BRANCH* 2.0.5 -> 2.1 -> 2.1.5 -> 2.1.6 -> 2.1.7.1 [2.1-STABLE ends] | (Mar 1997) | | | [2.2-STABLE] *BRANCH* 2.2.1 -> 2.2.2-RELEASE -> 2.2.5 -> 2.2.6 -> 2.2.7 -> 2.2.8 [end] | (Mar 1997) (Oct 97) (Apr 98) (Jul 98) (Dec 98) | | 3.0-SNAPs (started Q1 1997) | | 3.0-RELEASE (Oct 1998) | | [3.0-STABLE] *BRANCH* 3.1-RELEASE (Feb 1999) -> 3.2 -> 3.3 -> 3.4 -> 3.5 -> 3.5.1 | (May 1999) (Sep 1999) (Dec 1999) (June 2000) (July 2000) | | [4.0-STABLE] *BRANCH* 4.0 (Mar 2000) -> 4.1 -> 4.1.1 -> 4.2 -> 4.3 -> 4.4 -> ... future 4.x releases ... | | (July 2000) (Sep 2000) (Nov 2000) \|/ + [5.0-CURRENT continues] The 2.2-STABLE branch was retired with the release of 2.2.8. The 3-STABLE branch has ended with the release of 3.5.1, the final 3.X release. The only changes made to either of these branches will be, for the most part, security-related bug fixes. 4-STABLE is the actively developed -STABLE branch. The latest release on the 4-STABLE is &rel.current;-RELEASE, which was released in &rel.current.date;. The 5-CURRENT branch is slowly progressing toward 5.0-RELEASE and beyond. See What is FreeBSD-CURRENT? for more information on this branch. When are FreeBSD releases made? As a general principle, the FreeBSD core team only release a new version of FreeBSD when they believe that there are sufficient new features and/or bug fixes to justify one, and are satisfied that these new developments have been tested sufficiently to avoid compromising the stability of the release. Release dates are generally announced well in advance, so that the people working on the system know when their projects need to be finished and tested. Many users regard this caution as one of the best things about FreeBSD, although waiting for all the latest goodies to reach -STABLE can be a little frustrating. Releases are made about every 4 months on average. For people who need or want a little more excitement, binary snapshots are made every day as discussed above. Who is responsible for FreeBSD? The key decisions concerning the FreeBSD project, such as the overall direction of the project and who is allowed to add code to the source tree, are made by a core team of 9 people. There is a much larger team of more than 200 committers who are authorized to make changes directly to the FreeBSD source tree. However, most non-trivial changes are discussed in advance in the mailing lists, and there are no restrictions on who may take part in the discussion. Where can I get FreeBSD? Every significant release of FreeBSD is available via anonymous FTP from the FreeBSD FTP site: For the current 3.X-STABLE release, 3.5.1-RELEASE, see the 3.5.1-RELEASE directory. The current 4-STABLE release, &rel.current;-RELEASE can be found in the &rel.current;-RELEASE directory. 4.X snapshots are usually made once a day. 5.0 Snapshot releases are made once a day for the -CURRENT branch, these being of service purely to bleeding-edge testers and developers. Information about obtaining FreeBSD on CD, DVD, and other media can be found in the Handbook. How do I access the Problem Report database? The Problem Report database of all user change requests may be queried (or submitted to) by using our web-based PR submission and query interfaces. The &man.send-pr.1; command can also be used to submit problem reports and change requests via electronic mail. Before submitting a problem report, please read Writing FreeBSD Problem Reports, an article on how to write good problem reports. How do I become a FreeBSD Web mirror? There are multiple ways to mirror the Web pages. You can retrieve the formatted files from a FreeBSD CVSup server using the application net/cvsup. The file /usr/share/examples/cvsup/www-supfile contains an example CVSup configuration file for web mirrors. You can download the web site source code from any FreeBSD FTP server using your favorite ftp mirror tool. Keep in mind that you have to build these sources before publishing them. Start mirroring at ftp://ftp.FreeBSD.org/pub/FreeBSD/FreeBSD-current/www. What other sources of information are there? Please check the Documentation list on the main FreeBSD web site. Documentation and Support What good books are there about FreeBSD? The project produces a wide range of documentation, available from this link: http://www.FreeBSD.org/docs.html. In addition, the Bibliography at the end of this FAQ, and the one in the Handbook reference other recommended books. Is the documentation available in other formats, such as plain text (ASCII), or Postscript? Yes. The documentation is available in a number of different formats and compression schemes on the FreeBSD FTP site, in the /pub/FreeBSD/doc/ directory. The documentation is categorized in a number of different ways. These include: The document's name, such as faq, or handbook. The document's language and encoding. These are based on the locale names you will find under /usr/share/locale on your FreeBSD system. The current languages and encodings that we have for documentation are as follows: Name Meaning en_US.ISO8859-1 US English de_DE.ISO8859-1 German es_ES.ISO8859-1 Spanish fr_FR.ISO8859-1 French ja_JP.eucJP Japanese (EUC encoding) ru_RU.KOI8-R Russian (KOI8-R encoding) zh_TW.Big5 Chinese (Big5 encoding) Some documents may not be available in all languages. The document's format. We produce the documentation in a number of different output formats. Each format has its own advantages and disadvantages. Some formats are better suited for online reading, while others are meant to be aesthetically pleasing when printed on paper. Having the documentation available in any of these formats ensures that our readers will be able to read the parts they are interested in, either on their monitor, or on paper after printing the documents. The currently available formats are: Format Meaning html-split A collection of small, linked, HTML files. html One large HTML file containing the entire document pdb Palm Pilot database format, for use with the iSilo reader. pdf Adobe's Portable Document Format ps Postscript rtf Microsoft's Rich Text Format Page numbers are not automatically updated when loading this format in to Word. Press CTRLA, CTRLEND, F9 after loading the document, to update the page numbers. txt Plain text The compression and packaging scheme. There are three of these currently in use. Where the format is html-split, the files are bundled up using &man.tar.1;. The resulting .tar file is then compressed using the compression schemes detailed in the next point. All the other formats generate one file, called book.format (i.e., book.pdb, book.html, and so on). These files are then compressed using three compression schemes. Scheme Description zip The Zip format. If you want to uncompress this on FreeBSD you will need to install the archivers/unzip port first. gz The GNU Zip format. Use &man.gunzip.1; to uncompress these files, which is part of FreeBSD. bz2 The BZip2 format. Less widespread than the others, but generally gives smaller files. Install the archivers/bzip2 port to uncompress these files. So the Postscript version of the Handbook, compressed using BZip2 will be stored in a file called book.ps.bz2 in the handbook/ directory. The formatted documentation is also available as a FreeBSD package, of which more later. After choosing the format and compression mechanism that you want to download, you must then decide whether or not you want to download the document as a FreeBSD package. The advantage of downloading and installing the package is that the documentation can then be managed using the normal FreeBSD package management comments, such as &man.pkg.add.1; and &man.pkg.delete.1;. If you decide to download and install the package then you must know the filename to download. The documentation-as-packages files are stored in a directory called packages. Each package file looks like document-name.lang.encoding.format.tgz. For example, the FAQ, in English, formatted as PDF, is in the package called faq.en_US.ISO8859-1.pdf.tgz. Knowing this, you can use the following command to install the English PDF FAQ package. &prompt.root; pkg_add ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/packages/faq.en_US.ISO8859-1.pdf.tgz Having done that, you can use &man.pkg.info.1; to determine where the file has been installed. &prompt.root; pkg_info -f faq.en_US.ISO8859-1.pdf Information for faq.en_US.ISO8859-1.pdf: Packing list: Package name: faq.en_US.ISO8859-1.pdf CWD to /usr/share/doc/en_US.ISO8859-1/books/faq File: book.pdf CWD to . File: +COMMENT (ignored) File: +DESC (ignored) As you can see, book.pdf will have been installed in to /usr/share/doc/en_US.ISO8859-1/books/faq. If you do not want to use the packages then you will have to download the compressed files yourself, uncompress them, and then copy the appropriate documents in to place. For example, the split HTML version of the FAQ, compressed using &man.gzip.1;, can be found in the doc/en_US.ISO8859-1/books/faq/book.html-split.tar.gz file. To download and uncompress that file you would have to do this. &prompt.root; fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/en_US.ISO8859-1/books/faq/book.html-split.tar.gz &prompt.root; gzip -d book.html-split.tar.gz &prompt.root; tar xvf book.html-split.tar You will be left with a collection of .html files. The main one is called index.html, which will contain the table of contents, introductory material, and links to the other parts of the document. You can then copy or move these to their final location as necessary. Where do I find info on the FreeBSD mailing lists? You can find full information in the Handbook entry on mailing-lists. Where do I find the FreeBSD Y2K info? You can find full information in the FreeBSD Y2K page. What FreeBSD news groups are available? You can find full information in the Handbook entry on newsgroups. Are there FreeBSD IRC (Internet Relay Chat) channels? Yes, most major IRC networks host a FreeBSD chat channel: Channel #FreeBSD on EFNet is a FreeBSD forum, but do not go there for tech support or try to get folks there to help you avoid the pain of reading man pages or doing your own research. It is a chat channel, first and foremost, and topics there are just as likely to involve sex, sports or nuclear weapons as they are FreeBSD. You Have Been Warned! Available at server irc.chat.org. Channel #FreeBSDhelp on EFNet is a channel dedicated to helping FreeBSD users. They are much more sympathetic to questions then #FreeBSD is. Channel #FreeBSD on DALNET is available at irc.dal.net in the US and irc.eu.dal.net in Europe. Channel #FreeBSD on UNDERNET is available at us.undernet.org in the US and eu.undernet.org in Europe. Since it is a help channel, be prepared to read the documents you are referred to. Channel #FreeBSD on HybNet. This channel is a help channel. A list of servers can be found on the HybNet web site. Each of these channels are distinct and are not connected to each other. Their chat styles also differ, so you may need to try each to find one suited to your chat style. As with all types of IRC traffic, if you are easily offended or cannot deal with lots of young people (and more than a few older ones) doing the verbal equivalent of jello wrestling, do not even bother with it. Where can I get commercial FreeBSD training and support? DaemonNews provides commercial training and support for FreeBSD. More information can be found at their BSD Mall site. FreeBSD Services Ltd provide commercial support for FreeBSD in the UK (as well as selling FreeBSD on DVD). See their web site for more information. The FreeBSD Mall provides commercial FreeBSD support. You can get more information at their web site. Any other organizations providing training and support should contact the project in order to be listed here. Nik Clayton
nik@FreeBSD.org
 Installation Which file do I download to get FreeBSD? Prior to release 3.1, you only needed one floppy image to install FreeBSD, namely floppies/boot.flp. However, since release 3.1 the Project has added out-of-the-box support for a wide variety of hardware, which takes up more space. For 3.x and later you need two floppy images: floppies/kernel.flp and floppies/mfsroot.flp. These images need to be copied onto floppies by tools like fdimage or &man.dd.1;. If you need to download the distributions yourself (for a DOS filesystem install, for instance), below are some recommendations for distributions to grab: bin/ manpages/ compat*/ doc/ src/ssys.* Full instructions on this procedure and a little bit more about installation issues in general can be found in the Handbook entry on installing FreeBSD. What do I do if the floppy images does not fit on a single floppy? A 3.5 inch (1.44MB) floppy can accommodate 1474560 bytes of data. The boot image is exactly 1474560 bytes in size. Common mistakes when preparing the boot floppy are: Not downloading the floppy image in binary mode when using FTP. Some FTP clients default their transfer mode to ascii and attempt to change any end-of-line characters received to match the conventions used by the client's system. This will almost invariably corrupt the boot image. Check the size of the downloaded boot image: if it is not exactly that on the server, then the download process is suspect. To workaround: type binary at the FTP command prompt after getting connected to the server and before starting the download of the image. Using the DOS copy command (or equivalent GUI tool) to transfer the boot image to floppy. Programs like copy will not work as the boot image has been created to be booted into directly. The image has the complete content of the floppy, track for track, and is not meant to be placed on the floppy as a regular file. You have to transfer it to the floppy raw, using the low-level tools (e.g. fdimage or rawrite) described in the installation guide to FreeBSD. Where are the instructions for installing FreeBSD? Installation instructions can be found in the Handbook entry on installing FreeBSD. What do I need in order to run FreeBSD? You will need a 386 or better PC, with 5 MB or more of RAM and at least 60 MB of hard disk space. It can run with a low end MDA graphics card but to run X11R6, a VGA or better video card is needed. See also I have only 4 MB of RAM. Can I install FreeBSD? FreeBSD 2.1.7 was the last version of FreeBSD that could be installed on a 4MB system. FreeBSD 2.2 and later needs at least 5MB to install on a new system. All versions of FreeBSD will run in 4MB of RAM, they just cannot run the installation program in 4MB. You can add extra memory for the install process, if you like, and then after the system is up and running, go back to 4MB. Or you could swap your disk into a system which has >4MB, install onto the disk and then swap it back. FreeBSD 2.1.7 will not install with 640 kB base + 3 MB extended memory. If your motherboard can remap some of the lost memory out of the 640kB to 1MB region, then you may still be able to get FreeBSD 2.1.7 up. Try to go into your BIOS setup and look for a remap option. Enable it. You may also have to disable ROM shadowing. It may be easier to get 4 more MB just for the install. Build a custom kernel with only the options you need and then remove the 4MB out. You can also install 2.0.5 and then upgrade your system to 2.1.7 with the upgrade option of the 2.1.7 installation program. After the installation, if you build a custom kernel, it will run in 4 MB. Someone has even successfully booted with 2 MB, although the system was almost unusable. How can I make my own custom install floppy? Currently there is no way to just make a custom install floppy. You have to cut a whole new release, which will include your install floppy. To make a custom release, follow the instructions in the Release Engineering article. Can I have more than one operating system on my PC? Have a look at the multi-OS page. Can Windows 95/98 co-exist with FreeBSD? Install Windows 95/98 first, after that FreeBSD. FreeBSD's boot manager will then manage to boot Win95/98 and FreeBSD. If you install Windows 95/98 second, it will boorishly overwrite your boot manager without even asking. If that happens, see the next section. Windows 95/98 killed my boot manager! How do I get it back? You can reinstall the boot manager FreeBSD comes with in one of three ways: Running DOS, go into the tools/ directory of your FreeBSD distribution and look for bootinst.exe. You run it like so: ...\TOOLS> bootinst.exe boot.bin and the boot manager will be reinstalled. Boot the FreeBSD boot floppy again and go to the Custom installation menu item. Choose Partition. Select the drive which used to contain your boot manager (likely the first one) and when you come to the partition editor for it, as the very first thing (e.g. do not make any changes) select (W)rite. This will ask for confirmation, say yes, and when you get the Boot Manager selection prompt, be sure to select Boot Manager. This will re-write the boot manager to disk. Now quit out of the installation menu and reboot off the hard disk as normal. Boot the FreeBSD boot floppy (or CDROM) and choose the Fixit menu item. Select either the Fixit - floppy or CDROM #2 (the live file system + floppy or CDROM #2 (the live filesystem option) as appropriate and enter the fixit shell. Then execute the following command: Fixit# fdisk -B -b /boot/boot0 bootdevice substituting bootdevice for your real boot device such as ad0 (first IDE disk), ad4 (first IDE disk on auxiliary controller), da0 (first SCSI disk), etc. My A, T, or X series IBM Thinkpad locks up when I first booted up my FreeBSD installation. How can I solve this? A bug in early revisions of IBM's BIOS on these machines mistakenly identifies the FreeBSD partition as a potential FAT suspend-to-disk partition. When the BIOS tries to parse the FreeBSD partition it hangs. According to IBMIn an e-mail from Keith Frechette kfrechet@us.ibm.com., the following model/BIOS release numbers incorporate the fix. Model BIOS revision T20 IYET49WW or later T21 KZET22WW or later A20p IVET62WW or later A20m IWET54WW or later A21p KYET27WW or later A21m KXET24WW or later A21e KUET30WW It has been reported that later IBM BIOS revisions may have reintroduced the bug. This message from Jacques Vidrine to the &a.mobile; describes a procedure which may work if your newer IBM laptop does not boot FreeBSD properly, and you can upgrade or downgrade the BIOS.. If you have an earlier BIOS, and upgrading is not an option a workaround is to install FreeBSD, change the partition ID FreeBSD uses, and install new boot blocks that can handle the different partition ID. First, you will need to restore the machine to a state where it can get through its self-test screen. Doing this requires powering up the machine without letting it find a FreeBSD partition on its primary disk. One way is to remove the hard disk and temporarily move it to an older ThinkPad (such as a ThinkPad 600) or a desktop PC with an appropriate conversion cable. Once it is there, you can delete the FreeBSD partition and move the hard disk back. The ThinkPad should now be in a bootable state again. With the machine functional again, you can use the workaround procedure described here to get a working FreeBSD installation. Download boot1 and boot2 from http://people.FreeBSD.org/~bmah/ThinkPad/. Put these files somewhere you will be able to retrieve them later. Install FreeBSD as normal on to the ThinkPad. Do not use Dangerously Dedicated mode. Do not reboot when the install has finished. Either switch to the Emergency Holographic Shell (ALT F4) or start a fixit shell. Use &man.fdisk.8; to change the FreeBSD partition ID from 165 to 166 (this is the type used by OpenBSD). Bring the boot1 and boot2 files to the local filesystem. Use &man.disklabel.8; to write boot1 and boot2 to your FreeBSD slice. &prompt.root; disklabel -B -b boot1 -s boot2 ad0sn n is the number of the slice where you installed FreeBSD. Reboot. At the boot prompt you will be given the option of booting OpenBSD. This will actually boot FreeBSD. Getting this to work in the case where you want to dual boot OpenBSD and FreeBSD on the same laptop is left as an exercise for the reader. Can I install on a disk with bad blocks? Prior to 3.0, FreeBSD included a utility known as bad144, which automatically remapped bad blocks. Because modern IDE drives perform this function themselves, bad144 has been removed from the FreeBSD source tree. If you wish to install FreeBSD 3.0 or later, we strongly suggest you purchase a newer disk drive. If you do not wish to do this, you must run FreeBSD 2.x. If you are seeing bad block errors with a modern IDE drive, chances are the drive is going to die very soon (the drive's internal remapping functions are no longer sufficient to fix the bad blocks, which means the disk is heavily corrupted); we suggest you buy a new hard drive. If you have a SCSI drive with bad blocks, see this answer. I have just upgraded from 3.X to 4.X, and my first boot failed with bad sector table not supported FreeBSD 3.X and earlier supported bad144, which automatically remapped bad blocks. FreeBSD 4.X and later do not support this, as modern IDE drives include this functionality. See this question for more information. To fix this after an upgrade, you need to physically place the drive in a working system and use &man.disklabel.8; as discussed in the following questions. How do I tell if a drive has bad144 information on it before I try to upgrade to FreeBSD 4.0 and it fails? Use &man.disklabel.8; for this. disklabel -r drive device will give you the contents of your disk label. Look for a flags field. If you see flags: badsect, this drive is using bad144. For example, the following drive has bad144 enabled.: &prompt.root; disklabel -r wd0 # /dev/rwd0c: type: ESDI disk: wd0s1 label: flags: badsect bytes/sector: 512 sectors/track: 63 How do I remove bad144 from my pre-4.X system so I can upgrade safely? Use disklabel -e -rwd0 to edit the disklabel in place. Just remove the word badsect from the flags field, save, and exit. The bad144 file will still take up some space on your drive, but the disk itself will be usable. We still recommend you purchase a new disk if you have a large number of bad blocks. Strange things happen when I boot the install floppy! What is happening? If you are seeing things like the machine grinding to a halt or spontaneously rebooting when you try to boot the install floppy, here are three questions to ask yourself:- Did you use a new, freshly-formatted, error-free floppy (preferably a brand-new one straight out of the box, as opposed to the magazine cover disk that has been lying under the bed for the last three years)? Did you download the floppy image in binary (or image) mode? (do not be embarrassed, even the best of us have accidentally downloaded a binary file in ASCII mode at least once!) If you are using Windows95 or Win98 did you run fdimage or rawrite in pure DOS mode? These operating systems can interfere with programs that write directly to hardware, which the disk creation program does; even running it inside a DOS shell in the GUI can cause this problem. There have also been reports of Netscape causing problems when downloading the boot floppy, so it is probably best to use a different FTP client if you can. I booted from my ATAPI CDROM, but the install program says no CDROM is found. Where did it go? The usual cause of this problem is a mis-configured CDROM drive. Many PCs now ship with the CDROM as the slave device on the secondary IDE controller, with no master device on that controller. This is illegal according to the ATAPI specification, but Windows plays fast and loose with the specification, and the BIOS ignores it when booting. This is why the BIOS was able to see the CDROM to boot from it, but why FreeBSD cannot see it to complete the install. Reconfigure your system so that the CDROM is either the master device on the IDE controller it is attached to, or make sure that it is the slave on an IDE controller that also has a master device. Can I install on my laptop over PLIP (Parallel Line IP)? Yes. Use a standard Laplink cable. If necessary, you can check out the PLIP section of the Handbook for details on parallel port networking. If you are running FreeBSD 3.X or earlier, also look at the Mobile Computing page. Which geometry should I use for a disk drive? By the geometry of a disk, we mean the number of cylinders, heads and sectors/track on a disk. We will refer to this as C/H/S for convenience. This is how the PC's BIOS works out which area on a disk to read/write from. This causes a lot of confusion among new system administrators. First of all, the physical geometry of a SCSI drive is totally irrelevant, as FreeBSD works in term of disk blocks. In fact, there is no such thing as the physical geometry, as the sector density varies across the disk. What manufacturers claim is the physical geometry is usually the geometry that they have determined wastes the least space. For IDE disks, FreeBSD does work in terms of C/H/S, but all modern drives internally convert this into block references. All that matters is the logical geometry. This is the answer that the BIOS gets when it asks the drive what is your geometry? It then uses this geometry to access the disk. As FreeBSD uses the BIOS when booting, it is very important to get this right. In particular, if you have more than one operating system on a disk, they must all agree on the geometry. Otherwise you will have serious problems booting! For SCSI disks, the geometry to use depends on whether extended translation support is turned on in your controller (this is often referred to as support for DOS disks >1GB or something similar). If it is turned off, then use N cylinders, 64 heads and 32 sectors/track, where N is the capacity of the disk in MB. For example, a 2GB disk should pretend to have 2048 cylinders, 64 heads and 32 sectors/track. If it is turned on (it is often supplied this way to get around certain limitations in MSDOS) and the disk capacity is more than 1GB, use M cylinders, 63 sectors per track (not 64), and 255 heads, where 'M' is the disk capacity in MB divided by 7.844238 (!). So our example 2GB drive would have 261 cylinders, 63 sectors per track and 255 heads. If you are not sure about this, or FreeBSD fails to detect the geometry correctly during installation, the simplest way around this is usually to create a small DOS partition on the disk. The BIOS should then detect the correct geometry, and you can always remove the DOS partition in the partition editor if you do not want to keep it. You might want to leave it around for programming network cards and the like, however. Alternatively, there is a freely available utility distributed with FreeBSD called pfdisk.exe. You can find it in the tools subdirectory on the FreeBSD CDROM or on the various FreeBSD FTP sites. This program can be used to work out what geometry the other operating systems on the disk are using. You can then enter this geometry in the partition editor. Are there any restrictions on how I divide the disk up? Yes. You must make sure that your root partition is below 1024 cylinders so the BIOS can boot the kernel from it. (Note that this is a limitation in the PC's BIOS, not FreeBSD). For a SCSI drive, this will normally imply that the root partition will be in the first 1024MB (or in the first 4096MB if extended translation is turned on - see previous question). For IDE, the corresponding figure is 504MB. Is FreeBSD compatible with any disk managers? FreeBSD recognizes the Ontrack Disk Manager and makes allowances for it. Other disk managers are not supported. If you just want to use the disk with FreeBSD you do not need a disk manager. Just configure the disk for as much space as the BIOS can deal with (usually 504 megabytes), and FreeBSD should figure out how much space you really have. If you are using an old disk with an MFM controller, you may need to explicitly tell FreeBSD how many cylinders to use. If you want to use the disk with FreeBSD and another operating system, you may be able to do without a disk manager: just make sure the FreeBSD boot partition and the slice for the other operating system are in the first 1024 cylinders. If you are reasonably careful, a 20 megabyte boot partition should be plenty. When I boot FreeBSD I get Missing Operating System. What is happening? This is classically a case of FreeBSD and DOS or some other OS conflicting over their ideas of disk geometry. You will have to reinstall FreeBSD, but obeying the instructions given above will almost always get you going. Why can I not get past the boot manager's F? prompt? This is another symptom of the problem described in the preceding question. Your BIOS geometry and FreeBSD geometry settings do not agree! If your controller or BIOS supports cylinder translation (often marked as >1GB drive support), try toggling its setting and reinstalling FreeBSD. Do I need to install the complete sources? In general, no. However, we would strongly recommend that you install, at a minimum, the base source kit, which includes several of the files mentioned here, and the sys (kernel) source kit, which includes sources for the kernel. There is nothing in the system which requires the presence of the sources to operate, however, except for the kernel-configuration program &man.config.8;. With the exception of the kernel sources, our build structure is set up so that you can read-only mount the sources from elsewhere via NFS and still be able to make new binaries. (Because of the kernel-source restriction, we recommend that you not mount this on /usr/src directly, but rather in some other location with appropriate symbolic links to duplicate the top-level structure of the source tree.) Having the sources on-line and knowing how to build a system with them will make it much easier for you to upgrade to future releases of FreeBSD. To actually select a subset of the sources, use the Custom menu item when you are in the Distributions menu of the system installation tool. Do I need to build a kernel? Building a new kernel was originally pretty much a required step in a FreeBSD installation, but more recent releases have benefited from the introduction of a much friendlier kernel configuration tool. When at the FreeBSD boot prompt (boot:), use the flag and you will be dropped into a visual configuration screen which allows you to configure the kernel's settings for most common ISA cards. It is still recommended that you eventually build a new kernel containing just the drivers that you need, just to save a bit of RAM, but it is no longer a strict requirement for most systems. Should I use DES, Blowfish, or MD5 passwords and how do I specify which form my users receive? The default password format on FreeBSD is to use MD5-based passwords. These are believed to be more secure than the traditional Unix password format, which used a scheme based on the DES algorithm. DES passwords are still available if you need to share your password file with legacy operating systems which still use the less secure password format (they are available if you choose to install the crypto distribution in sysinstall, or by installing the crypto sources if building from source). Installing the crypto libraries will also allow you to use the Blowfish password format, which is more secure. Which password format to use for new passwords is controlled by the passwd_format login capability in /etc/login.conf, which takes values of des, blf (if these are available) or md5. See the &man.login.conf.5; manual page for more information about login capabilities. Why does the boot floppy start, but hang at the Probing Devices... screen? If you have a IDE Zip or Jaz drive installed, remove it and try again. The boot floppy can get confused by the drives. After the system is installed you can reconnect the drive. Hopefully this will be fixed in a later release. Why do I get a panic: can't mount root error when rebooting the system after installation? This error comes from confusion between the boot block's and the kernel's understanding of the disk devices. The error usually manifests on two-disk IDE systems, with the hard disks arranged as the master or single device on separate IDE controllers, with FreeBSD installed on the secondary IDE controller. The boot blocks think the system is installed on wd1 (the second BIOS disk) while the kernel assigns the first disk on the secondary controller device wd2. After the device probing, the kernel tries to mount what the boot blocks think is the boot disk, wd1, while it is really wd2, and fails. To fix the problem, do one of the following: For FreeBSD 3.3 and later, reboot the system and hit Enter at the Booting kernel in 10 seconds; hit [Enter] to interrupt prompt. This will drop you into the boot loader. Then type set root_disk_unit="disk_number" . disk_number will be 0 if FreeBSD is installed on the master drive on the first IDE controller, 1 if it is installed on the slave on the first IDE controller, 2 if it is installed on the master of the second IDE controller, and 3 if it is installed on the slave of the second IDE controller. Then type boot, and your system should boot correctly. To make this change permanent (ie so you do not have to do this every time you reboot or turn on your FreeBSD machine), put the line root_disk_unit="disk_number" in /boot/loader.conf.local . If using FreeBSD 3.2 or earlier, at the Boot: prompt, enter 1:wd(2,a)kernel and press Enter. If the system starts, then run the command echo "1:wd(2,a)kernel" > /boot.config to make it the default boot string. Move the FreeBSD disk onto the primary IDE controller, so the hard disks are consecutive. Rebuild your kernel, modify the wd configuration lines to read: controller wdc0 at isa? port "IO_WD1" bio irq 14 vector wdintr disk wd0 at wdc0 drive 0 # disk wd1 at wdc0 drive 1 # comment out this line controller wdc1 at isa? port "IO_WD2" bio irq 15 vector wdintr disk wd1 at wdc1 drive 0 # change from wd2 to wd1 disk wd2 at wdc1 drive 1 # change from wd3 to wd2 Install the new kernel. If you moved your disks and wish to restore the previous configuration, replace the disks in the desired configuration and reboot. Your system should boot successfully. What are the limits for memory? For memory, the limit is 4 gigabytes. This configuration has been tested, see wcarchive's configuration for more details. If you plan to install this much memory into a machine, you need to be careful. You will probably want to use ECC memory and to reduce capacitive loading use 9 chip memory modules versus 18 chip memory modules. What are the limits for ffs filesystems? For ffs filesystems, the maximum theoretical limit is 8 terabytes (2G blocks), or 16TB for the default block size of 8K. In practice, there is a soft limit of 1 terabyte, but with modifications filesystems with 4 terabytes are possible (and exist). The maximum size of a single ffs file is approximately 1G blocks (4TB) if the block size is 4K. Maximum file sizes fs block size 2.2.7-stable 3.0-current works should work 4K 4T-1 4T-1 4T-1 >4T 8K >32G 8T-1 >32G 32T-1 16K >128G 16T-1 >128G 32T-1 32K >512G 32T-1 >512G 64T-1 64K >2048G 64T-1 >2048G 128T-1
When the fs block size is 4K, triple indirect blocks work and everything should be limited by the maximum fs block number that can be represented using triple indirect blocks (approx. 1K^3 + 1K^2 + 1K), but everything is limited by a (wrong) limit of 1G-1 on fs block numbers. The limit on fs block numbers should be 2G-1. There are some bugs for fs block numbers near 2G-1, but such block numbers are unreachable when the fs block size is 4K. For block sizes of 8K and larger, everything should be limited by the 2G-1 limit on fs block numbers, but is actually limited by the 1G-1 limit on fs block numbers, except under -STABLE triple indirect blocks are unreachable, so the limit is the maximum fs block number that can be represented using double indirect blocks (approx. (blocksize/4)^2 + (blocksize/4)), and under -CURRENT exceeding this limit may cause problems. Using the correct limit of 2G-1 blocks does cause problems. Why do I get an error message, archsw.readin.failed after compiling and booting a new kernel? You can boot by specifying the kernel directly at the second stage, pressing any key when the | shows up before loader is started. More specifically, you have upgraded the source for your kernel, and installed a new kernel builtin from them without making world. This is not supported. Make world. How do I upgrade from 3.X -> 4.X? We strongly recommend that you use binary snapshots to do this. 4-STABLE snapshots are available at ftp://releng4.FreeBSD.org/. Because of the many changes between 3.X and 4-STABLE, a direct upgrade from source will probably fail. A source upgrade can be done, but only in stages. First, upgrade to the latest 3-STABLE (RELENG_3). Then upgrade to 4.1.1-RELEASE (RELENG_4_1_1_RELEASE). Finally, upgrade to 4-STABLE (RELENG_4). If you wish to upgrade using source, please see the FreeBSD Handbook for more information. Upgrading via source is never recommended for new users, and upgrading from 3.X to 4.X is even less so; make sure you have read the instructions carefully before attempting to upgrade via source. What are these security profiles? A security profile is a set of configuration options that attempts to achieve the desired ratio of security to convenience by enabling and disabling certain programs and other settings. For full details, see the Security Profile section of the Handbook's post-install chapter. Hardware compatibility Does FreeBSD support architectures other than the x86? Yes. FreeBSD currently runs on both Intel x86 and DEC (now Compaq) Alpha architectures. Interest has also been expressed in a port of FreeBSD to the SPARC architecture, join the &a.sparc; if you are interested in joining that project. Most recent additions to the list of upcoming platforms are IA-64 and PowerPC, join the &a.ia64; and/or the &a.ppc; for more information. For general discussion on new architectures, join the &a.platforms;. If your machine has a different architecture and you need something right now, we suggest you look at NetBSD or OpenBSD. I want to get a piece of hardware for my FreeBSD system. Which model/brand/type is best? This is discussed continually on the FreeBSD mailing lists. Since hardware changes so quickly, however, we expect this. We still strongly recommend that you read through the Hardware Notes and search the mailing list archives before asking about the latest and greatest hardware. Chances are a discussion about the type of hardware you are looking for took place just last week. If you are looking for a laptop, check the FreeBSD-mobile mailing list archives. Otherwise, you probably want the archives for FreeBSD-questions, or possibly a specific mailing list for a particular hardware type. What kind of hard drives does FreeBSD support? FreeBSD supports EIDE and SCSI drives (with a compatible controller; see the next section), and all drives using the original Western Digital interface (MFM, RLL, ESDI, and of course IDE). A few ESDI controllers that use proprietary interfaces may not work: stick to WD1002/3/6/7 interfaces and clones. Which SCSI controllers are supported? See the complete list in the current Hardware Notes. Which CDROM drives are supported by FreeBSD? Any SCSI drive connected to a supported controller is supported. The following proprietary CDROM interfaces are also supported: Mitsumi LU002 (8bit), LU005 (16bit) and FX001D (16bit 2x Speed). Sony CDU 31/33A Sound Blaster Non-SCSI CDROM Matsushita/Panasonic CDROM ATAPI compatible IDE CDROMs All non-SCSI cards are known to be extremely slow compared to SCSI drives, and some ATAPI CDROMs may not work. As of 2.2 the FreeBSD CDROM from the FreeBSD Mall supports booting directly from the CD. Which CD-RW drives are supported by FreeBSD? FreeBSD supports any ATAPI-compatible IDE CD-R or CD-RW drive. For FreeBSD versions 4.0 and later, see the man page for &man.burncd.8;. For earlier FreeBSD versions, see the examples in /usr/share/examples/atapi. FreeBSD also supports any SCSI CD-R or CD-RW drives. Install and use the cdrecord command from the ports or packages system, and make sure that you have the pass device compiled in your kernel. Does FreeBSD support ZIP drives? FreeBSD supports the SCSI ZIP drive out of the box, of course. The ZIP drive can only be set to run at SCSI target IDs 5 or 6, but if your SCSI host adapter's BIOS supports it you can even boot from it. It is not clear which host adapters support booting from targets other than 0 or 1, so you will have to consult your adapter's documentation if you would like to use this feature. ATAPI (IDE) Zip drives are supported in FreeBSD 2.2.6 and later releases. FreeBSD has contained support for Parallel Port Zip Drives since version 3.0. If you are using a sufficiently up to date version, then you should check that your kernel contains the scbus0, da0, ppbus0, and vp0 drivers (the GENERIC kernel contains everything except vp0). With all these drivers present, the Parallel Port drive should be available as /dev/da0s4. Disks can be mounted using mount /dev/da0s4 /mnt OR (for dos disks) mount_msdos /dev/da0s4 /mnt as appropriate. Also check out the FAQ on removable drives later in this chapter, and the note on formattingin the Administration chapter. Does FreeBSD support JAZ, EZ and other removable drives? Apart from the IDE version of the EZ drive, these are all SCSI devices, so they should all look like SCSI disks to FreeBSD, and the IDE EZ should look like an IDE drive. I am not sure how well FreeBSD supports changing the media out while running. You will of course need to dismount the drive before swapping media, and make sure that any external units are powered on when you boot the system so FreeBSD can see them. See this note on formatting. Which multi-port serial cards are supported by FreeBSD? There is a list of these in the Miscellaneous devices section of the handbook. Some unnamed clone cards have also been known to work, especially those that claim to be AST compatible. Check the &man.sio.4; man page to get more information on configuring such cards. Does FreeBSD support my USB keyboard? USB device support was added to FreeBSD 3.1. However, it is still in preliminary state and may not always work as of version 3.2. If you want to experiment with the USB keyboard support, follow the procedure described below. Use FreeBSD 3.2 or later. Add the following lines to your kernel configuration file, and rebuild the kernel. device uhci device ohci device usb device ukbd options KBD_INSTALL_CDEV In versions of FreeBSD before 4.0, use this instead: controller uhci0 controller ohci0 controller usb0 controller ukbd0 options KBD_INSTALL_CDEV Go to the /dev directory and create device nodes as follows: &prompt.root; cd /dev &prompt.root; ./MAKEDEV kbd0 kbd1 Edit /etc/rc.conf and add the following lines: usbd_enable="YES" usbd_flags="" After the system is rebooted, the AT keyboard becomes /dev/kbd0 and the USB keyboard becomes /dev/kbd1, if both are connected to the system. If there is the USB keyboard only, it will be /dev/ukbd0. If you want to use the USB keyboard in the console, you have to explicitly tell the console driver to use the existing USB keyboard. This can be done by running the following command as a part of system initialization. &prompt.root; kbdcontrol -k /dev/kbd1 < /dev/ttyv0 > /dev/null Note that if the USB keyboard is the only keyboard, it is accessed as /dev/kbd0, thus, the command should look like: &prompt.root; kbdcontrol -k /dev/kbd0 < /dev/ttyv0 > /dev/null /etc/rc.i386 is a good place to add the above command. Once this is done, the USB keyboard should work in the X environment as well without any special settings. Hot-plugging and unplugging of the USB keyboard may not work quite right yet. It is a good idea to connect the keyboard before you start the system and leave it connected until the system is shutdown to avoid troubles. See the &man.ukbd.4; man page for more information. I have an unusual bus mouse. How do I set it up? FreeBSD supports the bus mouse and the InPort bus mouse from such manufactures as Microsoft, Logitech and ATI. The bus device driver is compiled in the GENERIC kernel by default in FreeBSD versions 2.X, but not included in version 3.0 or later. If you are building a custom kernel with the bus mouse driver, make sure to add the following line to the kernel config file In FreeBSD 3.0 or before, add: device mse0 at isa? port 0x23c tty irq5 vector mseintr In FreeBSD 3.X, the line should be: device mse0 at isa? port 0x23c tty irq5 And in FreeBSD 4.X and later, the line should read: device mse0 at isa? port 0x23c irq5 Bus mice usually comes with dedicated interface cards. These cards may allow you to set the port address and the IRQ number other than shown above. Refer to the manual of your mouse and the &man.mse.4; man page for more information. How do I use my PS/2 (mouse port or keyboard) mouse? If you are running a post-2.2.5 version of FreeBSD, the necessary driver, psm, is included and enabled in the kernel. The kernel should detect your PS/2 mouse at boot time. If you are running a previous but relatively recent version of FreeBSD (2.1.x or better) then you can simply enable it in the kernel configuration menu at installation time, otherwise later with at the boot: prompt. It is disabled by default, so you will need to enable it explicitly. If you are running an older version of FreeBSD then you will have to add the following lines to your kernel configuration file and compile a new kernel. In FreeBSD 3.0 or earlier, the line should be: device psm0 at isa? port "IO_KBD" conflicts tty irq 12 vector psmintr In FreeBSD 3.1 or later, the line should be: device psm0 at isa? tty irq 12 In FreeBSD 4.0 or later, the line should be: device psm0 at atkbdc? irq 12 See the Handbook entry on configuring the kernel if you have no experience with building kernels. Once you have a kernel detecting psm0 correctly at boot time, make sure that an entry for psm0 exists in /dev. You can do this by typing: &prompt.root; cd /dev; sh MAKEDEV psm0 when logged in as root. Is it possible to make use of a mouse in any way outside the X Window system? If you are using the default console driver, syscons, you can use a mouse pointer in text consoles to cut & paste text. Run the mouse daemon, moused, and turn on the mouse pointer in the virtual console: &prompt.root; moused -p /dev/xxxx -t yyyy &prompt.root; vidcontrol -m on Where xxxx is the mouse device name and yyyy is a protocol type for the mouse. See the &man.moused.8; man page for supported protocol types. You may wish to run the mouse daemon automatically when the system starts. In version 2.2.1, set the following variables in /etc/sysconfig. mousedtype="yyyy" mousedport="xxxx" mousedflags="" In versions 2.2.2 to 3.0, set the following variables in /etc/rc.conf. moused_type="yyyy" moused_port="xxxx" moused_flags="" In 3.1 and later, assuming you have a PS/2 mouse, all you need to is add moused_enable="YES" to /etc/rc.conf. In addition, if you would like to be able to use the mouse daemon on all virtual terminals instead of just console at boot-time, add the following to /etc/rc.conf. allscreens_flags="-m on" Staring from FreeBSD 2.2.6, the mouse daemon is capable of determining the correct protocol type automatically unless the mouse is a relatively old serial mouse model. Specify auto the protocol to invoke automatic detection. When the mouse daemon is running, access to the mouse needs to be coordinated between the mouse daemon and other programs such as the X Window. Refer to another section on this issue. How do I cut and paste text with mouse in the text console? Once you get the mouse daemon running (see previous section), hold down the button 1 (left button) and move the mouse to select a region of text. Then, press the button 2 (middle button) or the button 3 (right button) to paste it at the text cursor. In versions 2.2.6 and later, pressing the button 2 will paste the text. Pressing the button 3 will extend the selected region of text. If your mouse does not have the middle button, you may wish to emulate it or remap buttons using moused options. See the &man.moused.8; man page for details. Does FreeBSD support any USB mice? Preliminary USB device support was added to FreeBSD 3.1. It did not always work through early versions of 3.X. As of FreeBSD 4.0, USB devices should work out of the box. If you want to experiment with the USB mouse support under FreeBSD 3.X, follow the procedure described below. Use FreeBSD 3.2 or later. Add the following lines to your kernel configuration file, and rebuild the kernel. device uhci device ohci device usb device ums In versions of FreeBSD before 4.0, use this instead: controller uhci0 controller ohci0 controller usb0 device ums0 Go to the /dev directory and create a device node as follows: &prompt.root; cd /dev &prompt.root; ./MAKEDEV ums0 Edit /etc/rc.conf and add the following lines: moused_enable="YES" moused_type="auto" moused_port="/dev/ums0" moused_flags="" usbd_enable="YES" usbd_flags="" See the previous section for more detailed discussion on moused. In order to use the USB mouse in the X session, edit XF86Config. If you are using XFree86 3.3.2 or later, be sure to have the following lines in the Pointer section: Device "/dev/sysmouse" Protocol "Auto" If you are using earlier versions of XFree86, be sure to have the following lines in the Pointer section: Device "/dev/sysmouse" Protocol "SysMouse" Refer to another section on the mouse support in the X environment. Hot-plugging and unplugging of the USB mouse may not work quite right yet. It is a good idea connect the mouse before you start the system and leave it connected until the system is shutdown to avoid trouble. My mouse has a fancy wheel and buttons. Can I use them in FreeBSD? The answer is, unfortunately, It depends. These mice with additional features require specialized driver in most cases. Unless the mouse device driver or the user program has specific support for the mouse, it will act just like a standard two, or three button mouse. For the possible usage of wheels in the X Window environment, refer to that section. Why does my wheel-equipped PS/2 mouse cause my mouse cursor to jump around the screen? The PS/2 mouse driver psm in FreeBSD versions 3.2 or earlier has difficulty with some wheel mice, including Logitech model M-S48 and its OEM siblings. Apply the following patch to /sys/i386/isa/psm.c and rebuild the kernel. Index: psm.c =================================================================== RCS file: /src/CVS/src/sys/i386/isa/Attic/psm.c,v retrieving revision 1.60.2.1 retrieving revision 1.60.2.2 diff -u -r1.60.2.1 -r1.60.2.2 --- psm.c 1999/06/03 12:41:13 1.60.2.1 +++ psm.c 1999/07/12 13:40:52 1.60.2.2 @@ -959,14 +959,28 @@ sc->mode.packetsize = vendortype[i].packetsize; /* set mouse parameters */ +#if 0 + /* + * A version of Logitech FirstMouse+ won't report wheel movement, + * if SET_DEFAULTS is sent... Don't use this command. + * This fix was found by Takashi Nishida. + */ i = send_aux_command(sc->kbdc, PSMC_SET_DEFAULTS); if (verbose >= 2) printf("psm%d: SET_DEFAULTS return code:%04x\n", unit, i); +#endif if (sc->config & PSM_CONFIG_RESOLUTION) { sc->mode.resolution = set_mouse_resolution(sc->kbdc, - (sc->config & PSM_CONFIG_RESOLUTION) - 1); + (sc->config & PSM_CONFIG_RESOLUTION) - 1); + } else if (sc->mode.resolution >= 0) { + sc->mode.resolution + = set_mouse_resolution(sc->kbdc, sc->dflt_mode.resolution); + } + if (sc->mode.rate > 0) { + sc->mode.rate = set_mouse_sampling_rate(sc->kbdc, sc->dflt_mode.rate); } + set_mouse_scaling(sc->kbdc, 1); /* request a data packet and extract sync. bits */ if (get_mouse_status(sc->kbdc, stat, 1, 3) < 3) { Versions later than 3.2 should be all right. How do I use the mouse/trackball/touchpad on my laptop? Please refer to the answer to the previous question. Also check out the Mobile Computing page. What types of tape drives are supported? FreeBSD supports SCSI and QIC-36 (with a QIC-02 interface). This includes 8-mm (aka Exabyte) and DAT drives. Some of the early 8-mm drives are not quite compatible with SCSI-2, and may not work well with FreeBSD. Does FreeBSD support tape changers? FreeBSD 2.2 supports SCSI changers using the &man.ch.4; device and the &man.chio.1; command. The details of how you actually control the changer can be found in the &man.chio.1; man page. If you are not using AMANDA or some other product that already understands changers, remember that they only know how to move a tape from one point to another, so you need to keep track of which slot a tape is in, and which slot the tape currently in the drive needs to go back to. Which sound cards are supported by FreeBSD? FreeBSD supports the SoundBlaster, SoundBlaster Pro, SoundBlaster 16, Pro Audio Spectrum 16, AdLib and Gravis UltraSound sound cards. There is also limited support for MPU-401 and compatible MIDI cards. Cards conforming to the Microsoft Sound System specification are also supported through the pcm driver. This is only for sound! This driver does not support CDROMs, SCSI or joysticks on these cards, except for the SoundBlaster. The SoundBlaster SCSI interface and some non-SCSI CDROMs are supported, but you cannot boot off this device. Workarounds for no sound from es1370 with pcm driver? You can run the following command every time the machine booted up: &prompt.root; mixer pcm 100 vol 100 cd 100 Which network cards does FreeBSD support? See the Ethernet cards section of the handbook for a more complete list. I do not have a math co-processor - is that bad? This will only affect 386/486SX/486SLC owners - other machines will have one built into the CPU. In general this will not cause any problems, but there are circumstances where you will take a hit, either in performance or accuracy of the math emulation code (see the section on FP emulation). In particular, drawing arcs in X will be VERY slow. It is highly recommended that you buy a math co-processor; it is well worth it. Some math co-processors are better than others. It pains us to say it, but nobody ever got fired for buying Intel. Unless you are sure it works with FreeBSD, beware of clones. What other devices does FreeBSD support? See the Handbook for the list of other devices supported. Does FreeBSD support power management on my laptop? FreeBSD supports APM on certain machines. Please look in the LINT kernel config file, searching for the APM keyword. Further information can be found in &man.apm.4;. Why does my Micron system hang at boot time? Certain Micron motherboards have a non-conforming PCI BIOS implementation that causes grief when FreeBSD boots because PCI devices do not get configured at their reported addresses. Disable the Plug and Play Operating System flag in the BIOS to work around this problem. More information can be found at http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron Why does FreeBSD not recognize my Adaptec SCSI controller card? The newer AIC789x series Adaptec chips are supported under the CAM SCSI framework which made its debut in 3.0. Patches against 2.2-STABLE are in ftp://ftp.FreeBSD.org/pub/FreeBSD/development/cam/. A CAM-enhanced boot floppy is available at http://people.FreeBSD.org/~abial/cam-boot/. In both cases read the README before beginning. Why is FreeBSD not finding my internal Plug & Play modem? You will need to add the modem's PnP ID to the PnP ID list in the serial driver. To enable Plug & Play support, compile a new kernel with controller pnp0 in the configuration file, then reboot the system. The kernel will print the PnP IDs of all the devices it finds. Copy the PnP ID from the modem to the table in /sys/i386/isa/sio.c, at about line 2777. Look for the string SUP1310 in the structure siopnp_ids[] to find the table. Build the kernel again, install, reboot, and your modem should be found. You may have to manually configure the PnP devices using the pnp command in the boot-time configuration with a command like pnp 1 0 enable os irq0 3 drq0 0 port0 0x2f8 to make the modem show. Does FreeBSD support software modems, such as Winmodems? FreeBSD supports many software modems via add-on software. The comms/ltmdm port adds support for modems based on the very popular Lucent LT chipset. The comms/mwavem port supports the modem in IBM Thinkpad 600 and 700 laptops. You cannot install FreeBSD via a software modem; this software must be installed after the OS is installed. How do I get the boot: prompt to show on the serial console? Build a kernel with options COMCONSOLE. Create /boot.config and place as the only text in the file. Unplug the keyboard from the system. See /usr/src/sys/i386/boot/biosboot/README.serial for information. Why does my 3Com PCI network card not work with my Micron computer? Certain Micron motherboards have a non-conforming PCI BIOS implementation that does not configure PCI devices at the addresses reported. This causes grief when FreeBSD boots. To work around this problem, disable the Plug and Play Operating System flag in the BIOS. More information on this problem is available at URL: http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron Does FreeBSD support Symmetric Multiprocessing (SMP)? SMP is supported in 3.0-STABLE and later releases only. SMP is not enabled in the GENERIC kernel, so you will have to recompile your kernel to enable SMP. Take a look at /sys/i386/conf/LINT to figure out what options to put in your kernel config file. The boot floppy hangs on a system with an ASUS K7V motherboard. How do I fix this? Go in to the BIOS setup and disable the boot virus protection. Troubleshooting What do I do when I have bad blocks on my hard drive? With SCSI drives, the drive should be capable of re-mapping these automatically. However, many drives are shipped with this feature disabled, for some mysterious reason... To enable this, you will need to edit the first device page mode, which can be done on FreeBSD by giving the command (as root) &prompt.root; scsi -f /dev/rsd0c -m 1 -e -P 3 and changing the values of AWRE and ARRE from 0 to 1:- AWRE (Auto Write Reallocation Enbld): 1 ARRE (Auto Read Reallocation Enbld): 1 The following paragraphs were submitted by Ted Mittelstaedt tedm@toybox.placo.com: For IDE drives, any bad block is usually a sign of potential trouble. All modern IDE drives come with internal bad-block remapping turned on. All IDE hard drive manufacturers today offer extensive warranties and will replace drives with bad blocks on them. If you still want to attempt to rescue an IDE drive with bad blocks, you can attempt to download the IDE drive manufacturer's IDE diagnostic program, and run this against the drive. Sometimes these programs can be set to force the drive electronics to rescan the drive for bad blocks and lock them out. For ESDI, RLL and MFM drives, bad blocks are a normal part of the drive and are no sign of trouble, generally. With a PC, the disk drive controller card and BIOS handle the task of locking out bad sectors. This is fine for operating systems like DOS that use BIOS code to access the disk. However, FreeBSD's disk driver does not go through BIOS, therefore a mechanism, bad144, exists that replaces this functionality. bad144 only works with the wd driver (which means it is not supported in FreeBSD 4.0), it is NOT able to be used with SCSI. bad144 works by entering all bad sectors found into a special file. One caveat with bad144 - the bad block special file is placed on the last track of the disk. As this file may possibly contain a listing for a bad sector that would occur near the beginning of the disk, where the /kernel file might be located, it therefore must be accessible to the bootstrap program that uses BIOS calls to read the kernel file. This means that the disk with bad144 used on it must not exceed 1024 cylinders, 16 heads, and 63 sectors. This places an effective limit of 500MB on a disk that is mapped with bad144. To use bad144, simply set the Bad Block scanning to ON in the FreeBSD fdisk screen during the initial install. This works up through FreeBSD 2.2.7. The disk must have less than 1024 cylinders. It is generally recommended that the disk drive has been in operation for at least 4 hours prior to this to allow for thermal expansion and track wandering. If the disk has more than 1024 cylinders (such as a large ESDI drive) the ESDI controller uses a special translation mode to make it work under DOS. The wd driver understands about these translation modes, IF you enter the translated geometry with the set geometry command in fdisk. You must also NOT use the dangerously dedicated mode of creating the FreeBSD partition, as this ignores the geometry. Also, even though fdisk will use your overridden geometry, it still knows the true size of the disk, and will attempt to create a too large FreeBSD partition. If the disk geometry is changed to the translated geometry, the partition MUST be manually created with the number of blocks. A quick trick to use is to set up the large ESDI disk with the ESDI controller, boot it with a DOS disk and format it with a DOS partition. Then, boot the FreeBSD install and in the fdisk screen, read off and write down the blocksize and block numbers for the DOS partition. Then, reset the geometry to the same that DOS uses, delete the DOS partition, and create a cooperative FreeBSD partition using the blocksize you recorded earlier. Then, set the partition bootable and turn on bad block scanning. During the actual install, bad144 will run first, before any filesystems are created. (you can view this with an Alt-F2) If it has any trouble creating the badsector file, you have set too large a disk geometry - reboot the system and start all over again (including repartitioning and reformatting with DOS). If remapping is enabled and you are seeing bad blocks, consider replacing the drive. The bad blocks will only get worse as time goes on. Why does FreeBSD not recognize my Bustek 742a EISA SCSI controller? This info is specific to the 742a but may also cover other Buslogic cards. (Bustek = Buslogic) There are 2 general versions of the 742a card. They are hardware revisions A-G, and revisions H - onwards. The revision letter is located after the Assembly number on the edge of the card. The 742a has 2 ROM chips on it, one is the BIOS chip and the other is the Firmware chip. FreeBSD does not care what version of BIOS chip you have but it does care about what version of firmware chip. Buslogic will send upgrade ROMs out if you call their tech support dept. The BIOS and Firmware chips are shipped as a matched pair. You must have the most current Firmware ROM in your adapter card for your hardware revision. The REV A-G cards can only accept BIOS/Firmware sets up to 2.41/2.21. The REV H- up cards can accept the most current BIOS/Firmware sets of 4.70/3.37. The difference between the firmware sets is that the 3.37 firmware supports round robin The Buslogic cards also have a serial number on them. If you have a old hardware revision card you can call the Buslogic RMA department and give them the serial number and attempt to exchange the card for a newer hardware revision. If the card is young enough they will do so. FreeBSD 2.1 only supports Firmware revisions 2.21 onward. If you have a Firmware revision older than this your card will not be recognized as a Buslogic card. It may be recognized as an Adaptec 1540, however. The early Buslogic firmware contains an AHA1540 emulation mode. This is not a good thing for an EISA card, however. If you have an old hardware revision card and you obtain the 2.21 firmware for it, you will need to check the position of jumper W1 to B-C, the default is A-B. Why does FreeBSD not detect my HP Netserver's SCSI controller? This is basically a known problem. The EISA on-board SCSI controller in the HP Netserver machines occupies EISA slot number 11, so all the true EISA slots are in front of it. Alas, the address space for EISA slots >= 10 collides with the address space assigned to PCI, and FreeBSD's auto-configuration currently cannot handle this situation very well. So now, the best you can do is to pretend there is no address range clash :), by bumping the kernel option EISA_SLOTS to a value of 12. Configure and compile a kernel, as described in the Handbook entry on configuring the kernel. Of course, this does present you with a chicken-and-egg problem when installing on such a machine. In order to work around this problem, a special hack is available inside UserConfig. Do not use the visual interface, but the plain command-line interface there. Simply type eisa 12 quit at the prompt, and install your system as usual. While it is recommended you compile and install a custom kernel anyway. Hopefully, future versions will have a proper fix for this problem. You cannot use a dangerously dedicated disk with an HP Netserver. See this note for more info. What is going on with my CMD640 IDE controller? It is broken. It cannot handle commands on both channels simultaneously. There is a workaround available now and it is enabled automatically if your system uses this chip. For the details refer to the manual page of the disk driver (man 4 wd). If you are already running FreeBSD 2.2.1 or 2.2.2 with a CMD640 IDE controller and you want to use the second channel, build a new kernel with options "CMD640" enabled. This is the default for 2.2.5 and later. I keep seeing messages like ed1: timeout. What do these messages mean? This is usually caused by an interrupt conflict (e.g., two boards using the same IRQ). FreeBSD prior to 2.0.5R used to be tolerant of this, and the network driver would still function in the presence of IRQ conflicts. However, with 2.0.5R and later, IRQ conflicts are no longer tolerated. Boot with the -c option and change the ed0/de0/... entry to match your board. If you are using the BNC connector on your network card, you may also see device timeouts because of bad termination. To check this, attach a terminator directly to the NIC (with no cable) and see if the error messages go away. Some NE2000 compatible cards will give this error if there is no link on the UTP port or if the cable is disconnected. Why did my 3COM 3C509 card stop working for no apparent reason? This card has a bad habit of losing its configuration information. Refresh your card's settings with the DOS utility 3c5x9.exe. My parallel printer is ridiculously slow. What can I do? If the only problem is that the printer is terribly slow, try changing your printer port mode as discussed in the Printer Setup section of the Handbook. Why do my programs occasionally die with Signal 11 errors? Signal 11 errors are caused when your process has attempted to access memory which the operating system has not granted it access to. If something like this is happening at seemingly random intervals then you need to start investigating things very carefully. These problems can usually be attributed to either: If the problem is occurring only in a specific application that you are developing yourself it is probably a bug in your code. If it is a problem with part of the base FreeBSD system, it may also be buggy code, but more often than not these problems are found and fixed long before us general FAQ readers get to use these bits of code (that is what -current is for). In particular, a dead giveaway that this is not a FreeBSD bug is if you see the problem when you are compiling a program, but the activity that the compiler is carrying out changes each time. For example, suppose you are running make buildworld, and the compile fails while trying to compile ls.c in to ls.o. If you then run make buildworld again, and the compile fails in the same place then this is a broken build -- try updating your sources and try again. If the compile fails elsewhere then this is almost certainly hardware. What you should do: In the first case you can use a debugger e.g. gdb to find the point in the program which is attempting to access a bogus address and then fix it. In the second case you need to verify that it is not your hardware at fault. Common causes of this include: Your hard disks might be overheating: Check the fans in your case are still working, as your disk (and perhaps other hardware might be overheating). The processor running is overheating: This might be because the processor has been overclocked, or the fan on the processor might have died. In either case you need to ensure that you have hardware running at what it is specified to run at, at least while trying to solve this problem. i.e. Clock it back to the default settings. If you are overclocking then note that it is far cheaper to have a slow system than a fried system that needs replacing! Also the wider community is not often sympathetic to problems on overclocked systems, whether you believe it is safe or not. Dodgy memory: If you have multiple memory SIMMS/DIMMS installed then pull them all out and try running the machine with each SIMM or DIMM individually and narrow the problem down to either the problematic DIMM/SIMM or perhaps even a combination. Over-optimistic Motherboard settings: In your BIOS settings, and some motherboard jumpers you have options to set various timings, mostly the defaults will be sufficient, but sometimes, setting the wait states on RAM too low, or setting the RAM Speed: Turbo option, or similar in the BIOS will cause strange behaviour. A possible idea is to set to BIOS defaults, but it might be worth noting down your settings first! Unclean or insufficient power to the motherboard. If you have any unused I/O boards, hard disks, or CDROMs in your system, try temporarily removing them or disconnecting the power cable from them, to see if your power supply can manage a smaller load. Or try another power supply, preferably one with a little more power (for instance, if your current power supply is rated at 250 Watts try one rated at 300 Watts). You should also read the SIG11 FAQ (listed below) which has excellent explanations of all these problems, albeit from a Linux viewpoint. It also discusses how memory testing software or hardware can still pass faulty memory. Finally, if none of this has helped it is possible that you have just found a bug in FreeBSD, and you should follow the instructions to send a problem report. There is an extensive FAQ on this at the SIG11 problem FAQ My system crashes with either Fatal trap 12: page fault in kernel mode, or panic:, and spits out a bunch of information. What should I do? The FreeBSD developers are very interested in these errors, but need some more information than just the error you see. Copy your full crash message. Then consult the FAQ section on kernel panics, build a debugging kernel, and get a backtrace. This might sound difficult, but you do not need any programming skills; you just have to follow the instructions. Why does the screen go black and lose sync when I boot? This is a known problem with the ATI Mach 64 video card. The problem is that this card uses address 2e8, and the fourth serial port does too. Due to a bug (feature?) in the &man.sio.4; driver it will touch this port even if you do not have the fourth serial port, and even if you disable sio3 (the fourth port) which normally uses this address. Until the bug has been fixed, you can use this workaround: Enter at the boot prompt. (This will put the kernel into configuration mode). Disable sio0, sio1, sio2 and sio3 (all of them). This way the sio driver does not get activated -> no problems. Type exit to continue booting. If you want to be able to use your serial ports, you will have to build a new kernel with the following modification: in /usr/src/sys/i386/isa/sio.c find the one occurrence of the string 0x2e8 and remove that string and the preceding comma (keep the trailing comma). Now follow the normal procedure of building a new kernel. Even after applying these workarounds, you may still find that the X Window System does not work properly. If this is the case, make sure that the XFree86 version you are using is at least XFree86 3.3.3 or higher. This version and upwards has built-in support for the Mach64 cards and even a dedicated X server for those cards. Why does FreeBSD only use 64 MB of RAM when my system has 128 MB of RAM installed? Due to the manner in which FreeBSD gets the memory size from the BIOS, it can only detect 16 bits worth of Kbytes in size (65535 Kbytes = 64MB) (or less... some BIOSes peg the memory size to 16M). If you have more than 64MB, FreeBSD will attempt to detect it; however, the attempt may fail. To work around this problem, you need to use the kernel option specified below. There is a way to get complete memory information from the BIOS, but we do not have room in the bootblocks to do it. Someday when lack of room in the bootblocks is fixed, we will use the extended BIOS functions to get the full memory information...but for now we are stuck with the kernel option. options "MAXMEM=n" Where n is your memory in Kilobytes. For a 128 MB machine, you would want to use 131072. Why does FreeBSD 2.0 panic with kmem_map too small!? The message may also be mb_map too small! The panic indicates that the system ran out of virtual memory for network buffers (specifically, mbuf clusters). You can increase the amount of VM available for mbuf clusters by adding: options "NMBCLUSTERS=n" to your kernel config file, where n is a number in the range 512-4096, depending on the number of concurrent TCP connections you need to support. I would recommend trying 2048 - this should get rid of the panic completely. You can monitor the number of mbuf clusters allocated/in use on the system with netstat -m (see &man.netstat.1;). The default value for NMBCLUSTERS is 512 + MAXUSERS * 16. Why do I get the error /kernel: proc: table is full? The FreeBSD kernel will only allow a certain number of processes to exist at one time. The number is based on the MAXUSERS option in the kernel configuration. MAXUSERS also affects various other in-kernel limits, such as network buffers (see this earlier question). If your machine is heavily loaded, you probably want to increase MAXUSERS. This will increase these other system limits in addition to the maximum number of processes. After FreeBSD 4.4, MAXUSERS became a tunable value that could be set with kern.maxusers in /boot/loader.conf. In earlier versions of FreeBSD, you need to adjust MAXUSERS in your kernel configuration. If your machine is lightly loaded, and you are simply running a very large number of processes, you can adjust this with the kern.maxproc sysctl. If these processes are being run by a single user, you will also need to adjust kern.maxprocperuid to be one less than your new kern.maxproc value. (It must be at least one less because one system program, &man.init.8;, must always be running.) To make a sysctl permanent across reboots, set this in /etc/sysctl.conf in recent versions of FreeBSD, or /etc/rc.local in older versions. Why do I get an error reading CMAP busy when rebooting with a new kernel? The logic that attempts to detect an out of date /var/db/kvm_*.db files sometimes fails and using a mismatched file can sometimes lead to panics. If this happens, reboot single-user and do: &prompt.root; rm /var/db/kvm_*.db What does the message ahc0: brkadrint, Illegal Host Access at seqaddr 0x0 mean? This is a conflict with an Ultrastor SCSI Host Adapter. During the boot process enter the kernel configuration menu and disable uha0, which is causing the problem. When I boot my system, I get the error ahc0: illegal cable configuration. My cabling is correct. What is going on? Your motherboard lacks the external logic to support automatic termination. Switch your SCSI BIOS to specify the correct termination for your configuration rather than automatic termination. The AIC7XXX driver cannot determine if the external logic for cable detection (and thus auto-termination) is available. The driver simply assumes that this support must exist if the configuration contained in the serial EEPROM is set to "automatic termination". Without the external cable detection logic the driver will often configure termination incorrectly, which can compromise the reliability of the SCSI bus. Why does Sendmail give me an error reading mail loops back to myself? This is answered in the sendmail FAQ as follows:- * I'm getting "Local configuration error" messages, such as: 553 relay.domain.net config error: mail loops back to myself 554 <user@domain.net>... Local configuration error How can I solve this problem? You have asked mail to the domain (e.g., domain.net) to be forwarded to a specific host (in this case, relay.domain.net) by using an MX record, but the relay machine does not recognize itself as domain.net. Add domain.net to /etc/mail/local-host-names (if you are using FEATURE(use_cw_file)) or add "Cw domain.net" to /etc/mail/sendmail.cf. The current version of the sendmail FAQ is no longer maintained with the sendmail release. It is however regularly posted to comp.mail.sendmail, comp.mail.misc, comp.mail.smail, comp.answers, and news.answers. You can also receive a copy via email by sending a message to mail-server@rtfm.mit.edu with the command send usenet/news.answers/mail/sendmail-faq as the body of the message. Why do full screen applications on remote machines misbehave? The remote machine may be setting your terminal type to something other than the cons25 terminal type required by the FreeBSD console. There are a number of possible work-arounds for this problem: After logging on to the remote machine, set your TERM shell variable to ansi or sco if the remote machine knows about these terminal types. Use a VT100 emulator like screen at the FreeBSD console. screen offers you the ability to run multiple concurrent sessions from one terminal, and is a neat program in its own right. Each screen window behaves like a VT100 terminal, so the TERM variable at the remote end should be set to vt100. Install the cons25 terminal database entry on the remote machine. The way to do this depends on the operating system on the remote machine. The system administration manuals for the remote system should be able to help you here. Fire up an X server at the FreeBSD end and login to the remote machine using an X based terminal emulator such as xterm or rxvt. The TERM variable at the remote host should be set to xterm or vt100. Why does my machine print calcru: negative time...? This can be caused by various hardware and/or software ailments relating to interrupts. It may be due to bugs but can also happen by nature of certain devices. Running TCP/IP over the parallel port using a large MTU is one good way to provoke this problem. Graphics accelerators can also get you here, in which case you should check the interrupt setting of the card first. A side effect of this problem are dying processes with the message SIGXCPU exceeded cpu time limit. For FreeBSD 3.0 and later from Nov 29, 1998 forward: If the problem cannot be fixed otherwise the solution is to set this sysctl variable: &prompt.root; sysctl -w kern.timecounter.method=1 This means a performance impact, but considering the cause of this problem, you probably will not notice. If the problem persists, keep the sysctl set to one and set the NTIMECOUNTER option in your kernel to increasingly large values. If by the time you have reached NTIMECOUNTER=20 the problem is not solved, interrupts are too hosed on your machine for reliable time keeping. I see pcm0 not found or my sound card is found as pcm1 but I have device pcm0 in my kernel config file. What is going on? This occurs in FreeBSD 3.x with PCI sound cards. The pcm0 device is reserved exclusively for ISA-based cards so, if you have a PCI card, then you will see this error, and your card will appear as pcm1. You cannot remove the warning by simply changing the line in the kernel config file to device pcm1 as this will result in pcm1 being reserved for ISA cards and your PCI card being found as pcm2 (along with the warning pcm1 not found). If you have a PCI sound card you will also have to make the snd1 device rather than snd0: &prompt.root; cd /dev &prompt.root; ./MAKEDEV snd1 This situation does not arise in FreeBSD 4.x as a lot of work has been done to make it more PnP-centric and the pcm0 device is no longer reserved exclusively for ISA cards Why is my PnP card no longer found (or found as unknown) since upgrading to FreeBSD 4.x? FreeBSD 4.x is now much more PnP-centric and this has had the side effect of some PnP devices (e.g. sound cards and internal modems) not working even though they worked under FreeBSD 3.x. The reasons for this behaviour are explained by the following e-mail, posted to the freebsd-questions mailing list by Peter Wemm, in answer to a question about an internal modem that was no longer found after an upgrade to FreeBSD 4.x (the comments in [] have been added to clarify the context.
The PNP bios preconfigured it [the modem] and left it laying around in port space, so [in 3.x] the old-style ISA probes found it there. Under 4.0, the ISA code is much more PnP-centric. It was possible [in 3.x] for an ISA probe to find a stray device and then for the PNP device id to match and then fail due to resource conflicts. So, it disables the programmable cards first so this double probing cannot happen. It also means that it needs to know the PnP id's for supported PnP hardware. Making this more user tweakable is on the TODO list.
To get the device working again requires finding its PnP id and adding it to the list that the ISA probes use to identify PnP devices. This is obtained using &man.pnpinfo.8; to probe the device, for example this is the output from &man.pnpinfo.8; for an internal modem: &prompt.root; pnpinfo Checking for Plug-n-Play devices... Card assigned CSN #1 Vendor ID PMC2430 (0x3024a341), Serial Number 0xffffffff PnP Version 1.0, Vendor Version 0 Device Description: Pace 56 Voice Internal Plug & Play Modem Logical Device ID: PMC2430 0x3024a341 #0 Device supports I/O Range Check TAG Start DF I/O Range 0x3f8 .. 0x3f8, alignment 0x8, len 0x8 [16-bit addr] IRQ: 4 - only one type (true/edge) [more TAG lines elided] TAG End DF End Tag Successfully got 31 resources, 1 logical fdevs -- card select # 0x0001 CSN PMC2430 (0x3024a341), Serial Number 0xffffffff Logical device #0 IO: 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 IRQ 5 0 DMA 4 0 IO range check 0x00 activate 0x01 The information you require is in the Vendor ID line at the start of the output. The hexadecimal number in parentheses (0x3024a341 in this example) is the PnP id and the string immediately before this (PMC2430) is a unique ASCII id. This information needs adding to the file /usr/src/sys/isa/sio.c. You should first make a backup of sio.c just in case things go wrong. You will also need it to make the patch to submit with your PR (you are going to submit a PR, are you not?) then edit sio.c and search for the line static struct isa_pnp_id sio_ids[] = { then scroll down to find the correct place to add the entry for your device. The entries look like this, and are sorted on the ASCII Vendor ID string which should be included in the comment to the right of the line of code along with all (if it will fit) or part of the Device Description from the output of &man.pnpinfo.8;: {0x0f804f3f, NULL}, /* OZO800f - Zoom 2812 (56k Modem) */ {0x39804f3f, NULL}, /* OZO8039 - Zoom 56k flex */ {0x3024a341, NULL}, /* PMC2430 - Pace 56 Voice Internal Modem */ {0x1000eb49, NULL}, /* ROK0010 - Rockwell ? */ {0x5002734a, NULL}, /* RSS0250 - 5614Jx3(G) Internal Modem */ Add the hexadecimal Vendor ID for your device in the correct place, save the file, rebuild your kernel, and reboot. Your device should now be found as an sio device as it was under FreeBSD 3.x Why do I get the error nlist failed when running, for example, top or systat? The problem is that the application you are trying to run is looking for a specific kernel symbol, but, for whatever reason, cannot find it; this error stems from one of two problems: Your kernel and userland are not synchronized (i.e., you built a new kernel but did not do an installworld, or vice versa), and thus the symbol table is different from what the user application thinks it is. If this is the case, simply complete the upgrade process (see /usr/src/UPDATING for the correct sequence). You are not using /boot/loader to load your kernel, but doing it directly from boot2 (see &man.boot.8;). While there is nothing wrong with bypassing /boot/loader, it generally does a better job of making the kernel symbols available to user applications. Why does it take so long to connect to my computer via ssh or telnet? The symptom: there is a long delay between the time the TCP connection is established and the time when the client software asks for a password (or, in &man.telnet.1;'s case, when a login prompt appears). The problem: more likely than not, the delay is caused by the server software trying to resolve the client's IP address into a hostname. Many servers, including the Telnet and SSH servers that come with FreeBSD, do this in order to, among other things, store the hostname in a log file for future reference by the administrator. The remedy: if the problem occurs whenever you connect from your computer (the client) to any server, the problem is with the client; likewise, if the problem only occurs when someone connects to your computer (the server) the problem is with the server. If the problem is with the client, the only remedy is to fix the DNS so the server can resolve it. If this is on a local network, consider it a server problem and keep reading; conversely, if this is on the global Internet, you will most likely need to contact your ISP and ask them to fix it for you. If the problem is with the server, and this is on a local network, you need to configure the server to be able to resolve address-to-hostname queries for your local address range. See the &man.hosts.5; and &man.named.8; manual pages for more information. If this is on the global Internet, the problem may be that your server's resolver is not functioning correctly. To check, try to look up another host--say, www.yahoo.com. If it does not work, that is your problem. What does stray IRQ mean? Stray IRQs are indications of hardware IRQ glitches, mostly from hardware that removes its interrupt request in the middle of the interrupt request acknowledge cycle. One has three options for dealing with this: Live with the warnings. All except the first 5 per irq are suppressed anyway. Break the warnings by changing 5 to 0 in isa_strayintr() so that all the warnings are suppressed. Break the warnings by installing parallel port hardware that uses irq 7 and the PPP driver for it (this happens on most systems), and install an ide drive or other hardware that uses irq 15 and a suitable driver for it. Why does file: table is full show up repeatedly in dmesg? This error message indicates you have exhausted the number of available file descriptors on your system. Please see the kern.maxfiles section of the Tuning Kernel Limits section of the Handbook for a discussion and solution. Why does the clock on my laptop keep incorrect time? Your laptop has two or more clocks, and FreeBSD has chosen to use the wrong one. Run &man.dmesg.8;, and check for lines that contain Timecounter. The last line printed is the one that FreeBSD chose, and will almost certainly be TSC. &prompt.root; dmesg | grep Timecounter Timecounter "i8254" frequency 1193182 Hz Timecounter "TSC" frequency 595573479 Hz You can confirm this by checking the kern.timecounter.hardware &man.sysctl.3;. &prompt.root; sysctl kern.timecounter.hardware kern.timecounter.hardware: TSC The BIOS may modify the TSC clock—perhaps to change the speed of the processor when running from batteries, or going in to a power saving mode, but FreeBSD is unaware of these adjustments, and appears to gain or lose time. In this example, the i8254 clock is also available, and can be selected by writing its name to the kern.timecounter.hardware &man.sysctl.3;. &prompt.root; sysctl -w kern.timecounter.hardware=i8254 kern.timecounter.hardware: TSC -> i8254 Your laptop should now start keeping more accurate time. To have this change automatically run at boot time, add the following line to /etc/sysctl.conf. kern.timecounter.hardware=i8254 Why did my laptop fail to correctly probe PC cards? This problem is common on laptops that boot more than one operating system. Some non-BSD operating systems leave PC card hardware in an inconsistent state. pccardd will detect the card as "(null)""(null)" instead of its actual model. You must remove all power from the PC card slot to fully reset the hardware. Completely power off the laptop. (Don't suspend it, don't let it go into standby; the power needs to be completely off.) Wait a few moments, and reboot. Your PC card should work now. Some laptop hardware lies when it claims to be off. If the above does not work shut down, remove the battery, wait a moment, replace the battery, and reboot. Why does FreeBSD's boot loader display Read error and stop after the BIOS screen? FreeBSD's boot loader is incorrectly recognizing the hard drive's geometry. This must be manually set within fdisk when creating or modifying FreeBSD's slice. The correct drive geometry values can be found within the machine's BIOS. Look for the number of cylinders, heads and sectors for the particular drive. Within &man.sysinstall.8;'s fdisk, hit G to set the drive geometry. A dialog will pop up requesting the number of cylinders, heads and sectors. Type the numbers found from the BIOS separates by forward slashes. 5000 cylinders, 250 sectors and 60 sectors would be entered as 5000/250/60 Press enter to set the values, and hit W to write the new partition table to the drive. Another operating system destroyed my Boot Manager. How do I get it back? Enter &man.sysinstall.8; and choose Configure, then Fdisk. Select the disk the Boot Manager resided on with the space key. Press W to write changes to the drive. A prompt will appear asking which boot loader to install. Select this, and it will be restored. What does the error swap_pager: indefinite wait buffer: mean? This means that a process is trying to page memory to disk, and the page attempt has hung trying to access the disk for more than 20 seconds. It might be caused by bad blocks on the disk drive, disk wiring, cables, or any other disk I/O-related hardware. If the drive itself is actually bad, you will also see disk errors in /var/log/messages and in the output of dmesg. Otherwise, check your cables and connections. Commercial Applications This section is still very sparse, though we are hoping, of course, that companies will add to it! :) The FreeBSD group has no financial interest in any of the companies listed here but simply lists them as a public service (and feels that commercial interest in FreeBSD can have very positive effects on FreeBSD's long-term viability). We encourage commercial software vendors to send their entries here for inclusion. See the Vendors page for a longer list. Where can I get an Office Suite for FreeBSD? The FreeBSD Mall offers a FreeBSD native version of VistaSource ApplixWare 5. ApplixWare is a rich full-featured, commercial Office Suite for FreeBSD containing a word processor, spreadsheet, presentation program, vector drawing package, and other applications. ApplixWare is offered as part of the FreeBSD Mall's BSD Desktop Edition. The Linux version of StarOffice works flawlessly on FreeBSD. The easiest way to install the Linux version of StarOffice is through the FreeBSD Ports collection. Future versions of the open-source OpenOffice suite should work as well. Where can I get Motif for FreeBSD? The Open Group has released the source code to Motif 2.1.30. You can install the open-motif package, or compile it from ports. Refer to the ports section of the Handbook for more information on how to do this. The Open Motif distribution only allows redistribution if it is running on an open source operating system. In addition, there are commercial distributions of the Motif software available. These, however, are not for free, but their license allows them to be used in closed-source software. Contact Apps2go for the least expensive ELF Motif 2.1.20 distribution for FreeBSD (either i386 or Alpha). There are two distributions, the development edition and the runtime edition (for much less). These distributions includes: OSF/Motif manager, xmbind, panner, wsm. Development kit with uil, mrm, xm, xmcxx, include and Imake files. Static and dynamic ELF libraries (for use with FreeBSD 3.0 and above). Demonstration applets. Be sure to specify that you want the FreeBSD version of Motif when ordering (do not forget to mention the architecture you want too)! Versions for NetBSD and OpenBSD are also sold by Apps2go. This is currently a FTP only download. More info Apps2go WWW page or sales@apps2go.com or support@apps2go.com or phone (817) 431 8775 or +1 817 431-8775 Contact Metro Link for an either ELF or a.out Motif 2.1 distribution for FreeBSD. This distribution includes: OSF/Motif manager, xmbind, panner, wsm. Development kit with uil, mrm, xm, xmcxx, include and Imake files. Static and dynamic libraries (specify ELF for use with FreeBSD 3.0 and later; or a.out for use with FreeBSD 2.2.8 and earlier). Demonstration applets. Preformatted man pages. Be sure to specify that you want the FreeBSD version of Motif when ordering! Versions for Linux are also sold by Metro Link. This is available on either a CDROM or for FTP download. Contact Xi Graphics for an a.out Motif 2.0 distribution for FreeBSD. This distribution includes: OSF/Motif manager, xmbind, panner, wsm. Development kit with uil, mrm, xm, xmcxx, include and Imake files. Static and dynamic libraries (for use with FreeBSD 2.2.8 and earlier). Demonstration applets. Preformatted man pages. Be sure to specify that you want the FreeBSD version of Motif when ordering! Versions for BSDI and Linux are also sold by Xi Graphics. This is currently a 4 diskette set... in the future this will change to a unified CD distribution like their CDE. Where can I get CDE for FreeBSD? Xi Graphics used to sell CDE for FreeBSD, but no longer do. KDE is an open source X11 desktop which is similar to CDE in many respects. You might also like the look and feel of xfce. KDE and xfce are both in the ports system. Are there any commercial high-performance X servers? Yes, Xi Graphics and Metro Link sell Accelerated-X product for FreeBSD and other Intel based systems. The Metro Link offering is a high performance X Server that offers easy configuration using the FreeBSD Package suite of tools, support for multiple concurrent video boards and is distributed in binary form only, in a convenient FTP download. Not to mention the Metro Link offering is available at the very reasonable price of $39. Metro Link also sells both ELF and a.out Motif for FreeBSD (see above). More info Metro Link WWW page or sales@metrolink.com or tech@metrolink.com or phone (954) 938-0283 or +1 954 938-0283 The Xi Graphics offering is a high performance X Server that offers easy configuration, support for multiple concurrent video boards and is distributed in binary form only, in a unified diskette distribution for FreeBSD and Linux. Xi Graphics also offers a high performance X Server tailored for laptop support. There is a free compatibility demo of version 5.0 available. Xi Graphics also sells Motif and CDE for FreeBSD (see above). More info Xi Graphics WWW page or sales@xig.com or support@xig.com or phone (800) 946 7433 or +1 303 298-7478. Are there any Database systems for FreeBSD? Yes! See the Commercial Vendors section of FreeBSD's Web site. Also see the Databases section of the Ports collection. Can I run Oracle on FreeBSD? Yes. The following pages tell you exactly how to setup Linux-Oracle on FreeBSD: http://www.scc.nl/~marcel/howto-oracle.html http://www.lf.net/lf/pi/oracle/install-linux-oracle-on-freebsd User Applications So, where are all the user applications? Please take a look at the ports page for info on software packages ported to FreeBSD. The list currently tops &os.numports; and is growing daily, so come back to check often or subscribe to the freebsd-announce mailing list for periodic updates on new entries. Most ports should be available for the 2.2, 3.x and 4.x branches, and many of them should work on 2.1.x systems as well. Each time a FreeBSD release is made, a snapshot of the ports tree at the time of release in also included in the ports/ directory. We also support the concept of a package, essentially no more than a gzipped binary distribution with a little extra intelligence embedded in it for doing whatever custom installation work is required. A package can be installed and uninstalled again easily without having to know the gory details of which files it includes. Use the package installation menu in /stand/sysinstall (under the post-configuration menu item) or invoke the &man.pkg.add.1; command on the specific package files you are interested in installing. Package files can usually be identified by their .tgz suffix and CDROM distribution people will have a packages/All directory on their CD which contains such files. They can also be downloaded over the net for various versions of FreeBSD at the following locations: for 2.2.8-RELEASE/2.2.8-STABLE ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-2.2.8/ for 3.X-RELEASE/3.X-STABLE ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-3-stable/ for 4.X-RELEASE/4-STABLE ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/ for 5.X-CURRENT ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current or your nearest local mirror site. Note that all ports may not be available as packages since new ones are constantly being added. It is always a good idea to check back periodically to see which packages are available at the ftp.FreeBSD.org master site. Where do I find libc.so.3.0? You are trying to run a package built on 2.2 and later on a 2.1.x system. Please take a look at the previous section and get the correct port/package for your system. Why do I get a message reading Error: can't find libc.so.4.0? You accidently downloaded packages meant for 4.X and 5.X systems and attempted to install them on your 2.X or 3.X FreeBSD system. Please download the correct version of the packages. Why does ghostscript give lots of errors with my 386/486SX? You do not have a math co-processor, right? You will need to add the alternative math emulator to your kernel; you do this by adding the following to your kernel config file and it will be compiled in. options GPL_MATH_EMULATE You will need to remove the MATH_EMULATE option when you do this. Why do SCO/iBCS2 applications bomb on socksys? (FreeBSD 3.0 and older only). You first need to edit the /etc/sysconfig (or /etc/rc.conf, see &man.rc.conf.5;) file in the last section to change the following variable to YES: # Set to YES if you want ibcs2 (SCO) emulation loaded at startup ibcs2=NO It will load the ibcs2 kernel module at startup. You will then need to set up /compat/ibcs2/dev to look like: lrwxr-xr-x 1 root wheel 9 Oct 15 22:20 X0R@ -> /dev/null lrwxr-xr-x 1 root wheel 7 Oct 15 22:20 nfsd@ -> socksys -rw-rw-r-- 1 root wheel 0 Oct 28 12:02 null lrwxr-xr-x 1 root wheel 9 Oct 15 22:20 socksys@ -> /dev/null crw-rw-rw- 1 root wheel 41, 1 Oct 15 22:14 spx You just need socksys to go to /dev/null (see &man.null.4;) to fake the open & close. The code in -CURRENT will handle the rest. This is much cleaner than the way it was done before. If you want the spx driver for a local socket X connection, define SPX_HACK when you compile the system. How do I configure INN (Internet News) for my machine? After installing the news/inn package or port, an excellent place to start is Dave Barr's INN Page where you will find the INN FAQ. What version of Microsoft FrontPage should I get? Use the Port, Luke! A pre-patched version of Apache, apache13-fp, is available in the ports tree. Does FreeBSD support Java? Yes. Please see http://www.FreeBSD.org/java/. Why can I not build this port on my 3.X-STABLE machine? If you are running a FreeBSD version that lags significantly behind -CURRENT or -STABLE, you may need a ports upgrade kit from http://www.FreeBSD.org/ports/. If you are up to date, then someone might have committed a change to the port which works for -CURRENT but which broke the port for -STABLE. Please submit a bug report on this with the &man.send-pr.1; command, since the ports collection is supposed to work for both the -CURRENT and -STABLE branches. Where do I find ld.so? a.out applications like Netscape Navigator require a.out libraries. A version of FreeBSD built with ELF libraries does not install them by default. You will get complaints about not having /usr/libexec/ld.so if this is the case on your system. These libraries are available as an add-on in the compat22 distribution. Use &man.sysinstall.8; to install them. You can also install them from the FreeBSD source code: &prompt.root; cd /usr/src/lib/compat/compat22 &prompt.root; make install clean If you want to install the latest compat22 libraries whenever you run make world, edit /etc/make.conf to include COMPAT22=YES. Old compatibility libraries change rarely, if ever, so this is not generally needed. Also see the ERRATAs for 3.1-RELEASE and 3.2-RELEASE. I updated the sources, now how do I update my installed ports? FreeBSD does not include a port upgrading tool, but it does have some tools to make the upgrade process somewhat easier. You can also install additional tools to simplify port handling. The &man.pkg.version.1; command can generate a script that will update installed ports to the latest version in the ports tree. &prompt.root; pkg_version > /tmp/myscript The output script must be edited by hand before you use it. Current versions of &man.pkg.version.1; force this by inserting an &man.exit.1; at the beginning of the script. You should save the output of the script, as it will note packages that depend on the one that has been updated. These may or may not need to be updated as well. The usual case where they need to be updated is that a shared library has changed version numbers, so the ports that used that library need to be rebuilt to use the new version. If you have the disk space, you can use the portupgrade tool to automate all of this. portupgrade includes various tools to simplify package handling. It is available under sysutils/portupgrade. Since it is written in Ruby, portupgrade is an unlikely candidate for integration with the main FreeBSD tree. That should not stop anyone from using it, however. If your system is up full time, the &man.periodic.8; system can be used to generate a weekly list of ports that might need updating by setting weekly_status_pkg_enable="YES" in /etc/periodic.conf. Why is /bin/sh so minimal? Why does FreeBSD not use bash or another shell? Because POSIX says that there shall be such a shell. The more complicated answer: many people need to write shell scripts which will be portable across many systems. That is why POSIX specifies the shell and utility commands in great detail. Most scripts are written in Bourne shell, and because several important programming interfaces (&man.make.1;, &man.system.3;, &man.popen.3;, and analogues in higher-level scripting languages like Perl and Tcl) are specified to use the Bourne shell to interpret commands. Because the Bourne shell is so often and widely used, it is important for it to be quick to start, be deterministic in its behavior, and have a small memory footprint. The existing implementation is our best effort at meeting as many of these requirements simultaneously as we can. In order to keep /bin/sh small, we have not provided many of the convenience features that other shells have. That is why the Ports Collection includes more featureful shells like bash, scsh, tcsh, and zsh. (You can compare for yourself the memory utilization of all these shells by looking at the VSZ and RSS columns in a ps -u listing.) Why do Netscape and Opera take so long to start? The usual answer is that DNS on your system is misconfigured. Both Netscape and Opera perform DNS checks when starting up. The browser will not appear on your desktop until the program either gets a response or determines that the system has no network connection. Kernel Configuration I would like to customize my kernel. Is it difficult? Not at all! Check out the kernel config section of the Handbook. We recommend that you make a dated snapshot of your new /kernel called /kernel.YYMMDD after you get it working properly. Also back up your new /modules directory to /modules.YYMMDD. That way, if you make a mistake the next time you play with your configuration you can boot the backup kernel instead of having to fall back to kernel.GENERIC. This is particularly important if you are now booting from a controller that GENERIC does not support. My kernel compiles fail because _hw_float is missing. How do I solve this problem? Let me guess. You removed npx0 (see &man.npx.4;) from your kernel configuration file because you do not have a math co-processor, right? Wrong! :-) The npx0 is MANDATORY. Even if you do not have a mathematic co-processor, you must include the npx0 device. Why is my kernel so big (over 10MB)? Chances are, you compiled your kernel in debug mode. Kernels built in debug mode contain many symbols that are used for debugging, thus greatly increasing the size of the kernel. Note that if you running a FreeBSD 3.0 or later system, there will be little or no performance decrease from running a debug kernel, and it is useful to keep one around in case of a system panic. However, if you are running low on disk space, or you simply do not want to run a debug kernel, make sure that both of the following are true: You do not have a line in your kernel configuration file that reads: makeoptions DEBUG=-g You are not running &man.config.8; with the option. Both of the above situations will cause your kernel to be built in debug mode. As long as you make sure you follow the steps above, you can build your kernel normally, and you should notice a fairly large size decrease; most kernels tend to be around 1.5MB to 2MB. Why do I get interrupt conflicts with multi-port serial code? When I compile a kernel with multi-port serial code, it tells me that only the first port is probed and the rest skipped due to interrupt conflicts. How do I fix this? The problem here is that FreeBSD has code built-in to keep the kernel from getting trashed due to hardware or software conflicts. The way to fix this is to leave out the IRQ settings on all but one port. Here is a example: # # Multiport high-speed serial line - 16550 UARTS # device sio2 at isa? port 0x2a0 tty irq 5 flags 0x501 vector siointr device sio3 at isa? port 0x2a8 tty flags 0x501 vector siointr device sio4 at isa? port 0x2b0 tty flags 0x501 vector siointr device sio5 at isa? port 0x2b8 tty flags 0x501 vector siointr Why does every kernel I try to build fail to compile, even GENERIC? There are a number of possible causes for this problem. They are, in no particular order: You are not using the new make buildkernel and make installkernel targets, and your source tree is different from the one used to build the currently running system (e.g., you are compiling 4.3-RELEASE on a 4.0-RELEASE system). If you are attempting an upgrade, please read the /usr/src/UPDATING file, paying particular attention to the COMMON ITEMS section at the end. You are using the new make buildkernel and make installkernel targets, but you failed to assert the completion of the make buildworld target. The make buildkernel target relies on files generated by the make buildworld target to complete its job correctly. Even if you are trying to build FreeBSD-STABLE, it is possible that you fetched the source tree at a time when it was either being modified, or broken for other reasons; only releases are absolutely guaranteed to be buildable, although FreeBSD-STABLE builds fine the majority of the time. If you have not already done so, try re-fetching the source tree and see if the problem goes away. Try using a different server in case the one you are using is having problems. Disks, Filesystems, and Boot Loaders How can I add my new hard disk to my FreeBSD system? See the Disk Formatting Tutorial at www.FreeBSD.org. How do I move my system over to my huge new disk? The best way is to reinstall the OS on the new disk, then move the user data over. This is highly recommended if you have been tracking -stable for more than one release, or have updated a release instead of installing a new one. You can install booteasy on both disks with &man.boot0cfg.8;, and dual boot them until you are happy with the new configuration. Skip the next paragraph to find out how to move the data after doing this. Should you decide not to do a fresh install, you need to partition and label the new disk with either /stand/sysinstall, or &man.fdisk.8; and &man.disklabel.8;. You should also install booteasy on both disks with &man.boot0cfg.8;, so that you can dual boot to the old or new system after the copying is done. See the formatting-media article for details on this process. Now you have the new disk set up, and are ready to move the data. Unfortunately, you cannot just blindly copy the data. Things like device files (in /dev), flags, and links tend to screw that up. You need to use tools that understand these things, which means &man.dump.8;. Although it is suggested that you move the data in single user mode, it is not required. You should never use anything but &man.dump.8; and - &man.restore.8; to move the root file system. The + &man.restore.8; to move the root filesystem. The &man.tar.1; command may work - then again, it may not. You should also use &man.dump.8; and &man.restore.8; if you are moving a single partition to another empty partition. The sequence of steps to use dump to move a partitions data to a new partition is: newfs the new partition. mount it on a temporary mount point. cd to that directory. dump the old partition, piping output to the new one. For example, if you are going to move root to /dev/ad1s1a, with /mnt as the temporary mount point, it is: &prompt.root; newfs /dev/ad1s1a &prompt.root; mount /dev/ad1s1a /mnt &prompt.root; cd /mnt &prompt.root; dump 0af - / | restore xf - Rearranging your partitions with dump takes a bit more work. To merge a partition like /var into its parent, create the new partition large enough for both, move the parent partition as described above, then move the child partition into the empty directory that the first move created: &prompt.root; newfs /dev/ad1s1a &prompt.root; mount /dev/ad1s1a /mnt &prompt.root; cd /mnt &prompt.root; dump 0af - / | restore xf - &prompt.root; cd var &prompt.root; dump 0af - /var | restore xf - To split a directory from its parent, say putting /var on its own partition when it was not before, create both partitions, then mount the child partition on the appropriate directory in the temporary mount point, then move the old single partition: &prompt.root; newfs /dev/ad1s1a &prompt.root; newfs /dev/ad1s1d &prompt.root; mount /dev/ad1s1a /mnt &prompt.root; mkdir /mnt/var &prompt.root; mount /dev/ad1s1d /mnt/var &prompt.root; cd /mnt &prompt.root; dump 0af - / | restore xf - You might prefer &man.cpio.1;, &man.pax.1;, &man.tar.1; to &man.dump.8; for user data. At the time of this writing, these are known to lose file flag information, so use them with caution. Will a dangerously dedicated disk endanger my health? The installation procedure allows you to chose two different methods in partitioning your hard disk(s). The default way makes it compatible with other operating systems on the same machine, by using fdisk table entries (called slices in FreeBSD), with a FreeBSD slice that employs partitions of its own. Optionally, one can chose to install a boot-selector to switch between the possible operating systems on the disk(s). The alternative uses the entire disk for FreeBSD, and makes no attempt to be compatible with other operating systems. So why it is called dangerous? A disk in this mode does not contain what normal PC utilities would consider a valid fdisk table. Depending on how well they have been designed, they might complain at you once they are getting in contact with such a disk, or even worse, they might damage the BSD bootstrap without even asking or notifying you. In addition, the dangerously dedicated disk's layout is known to confuse many BIOSes, including those from AWARD (e.g. as found in HP Netserver and Micronics systems as well as many others) and Symbios/NCR (for the popular 53C8xx range of SCSI controllers). This is not a complete list, there are more. Symptoms of this confusion include the read error message printed by the FreeBSD bootstrap when it cannot find itself, as well as system lockups when booting. Why have this mode at all then? It only saves a few kbytes of disk space, and it can cause real problems for a new installation. Dangerously dedicated mode's origins lie in a desire to avoid one of the most common problems plaguing new FreeBSD installers - matching the BIOS geometry numbers for a disk to the disk itself. Geometry is an outdated concept, but one still at the heart of the PC's BIOS and its interaction with disks. When the FreeBSD installer creates slices, it has to record the location of these slices on the disk in a fashion that corresponds with the way the BIOS expects to find them. If it gets it wrong, you will not be able to boot. Dangerously dedicated mode tries to work around this by making the problem simpler. In some cases, it gets it right. But it is meant to be used as a last-ditch alternative - there are better ways to solve the problem 99 times out of 100. So, how do you avoid the need for DD mode when you are installing? Start by making a note of the geometry that your BIOS claims to be using for your disks. You can arrange to have the kernel print this as it boots by specifying at the boot: prompt, or using boot -v in the loader. Just before the installer starts, the kernel will print a list of BIOS geometries. Do not panic - wait for the installer to start and then use scrollback to read the numbers. Typically the BIOS disk units will be in the same order that FreeBSD lists your disks, first IDE, then SCSI. When you are slicing up your disk, check that the disk geometry displayed in the FDISK screen is correct (ie. it matches the BIOS numbers); if it is wrong, use the g key to fix it. You may have to do this if there is absolutely nothing on the disk, or if the disk has been moved from another system. Note that this is only an issue with the disk that you are going to boot from; FreeBSD will sort itself out just fine with any other disks you may have. Once you have got the BIOS and FreeBSD agreeing about the geometry of the disk, your problems are almost guaranteed to be over, and with no need for DD mode at all. If, however, you are still greeted with the dreaded read error message when you try to boot, it is time to cross your fingers and go for it - there is nothing left to lose. To return a dangerously dedicated disk for normal PC use, there are basically two options. The first is, you write enough NULL bytes over the MBR to make any subsequent installation believe this to be a blank disk. You can do this for example with &prompt.root; dd if=/dev/zero of=/dev/rda0 count=15 Alternatively, the undocumented DOS feature C:\> fdisk /mbr will to install a new master boot record as well, thus clobbering the BSD bootstrap. Which partitions can safely use softupdates? I have heard that softupdates on / can cause problems. Short answer: you can usually use softupdates safely on all partitions. Long answer: There used to be some concern over using softupdates on the root partition. Softupdates has two characteristics that caused this. First, a softupdates partition has a small chance of losing data during a system crash. (The partition will not be corrupted; the data will simply be lost.) Also, softupdates can cause temporary space shortages. When using softupdates, the kernel can take up to thirty seconds to actually write changes to the physical disk. If you delete a large file, the file still resides on disk until the kernel actually performs the deletion. This can cause a very simple race condition. Suppose you delete one large file and immediately create another large file. The first large file is not yet actually removed from the physical disk, so the disk might not have enough room for the second large file. You get an error that the partition does not have enough space, although you know perfectly well that you just released a large chunk of space! When you try again mere seconds later, the file creation works as you expect. This has left more than one user scratching his head and doubting his sanity, the FreeBSD filesystem, or both. If a system should crash after the kernel accepts a chunk of data for writing to disk, but before that data is actually written out, data could be lost or corrupted. This risk is extremely small, but generally manageable. Use of IDE write caching greatly increases this risk; it is strongly recommended that you disable IDE write caching when using softupdates. These issues affect all partitions using softupdates. So, what does this mean for the root partition? Vital information on the root partition changes very rarely. Files such as /kernel and the contents of /etc only change during system maintenance, or when users change their passwords. If the system crashed during the thirty-second window after such a change is made, it is possible that data could be lost. This risk is negligible for most applications, but you should be aware that it exists. If your system cannot tolerate this much risk, do not use softupdates on the root filesystem! / is traditionally one of the smallest partitions. By default, FreeBSD puts the /tmp directory on /. If you have a busy /tmp, you might see intermittent space problems. Symlinking /tmp to /var/tmp will solve this problem. What is inappropriate about my ccd? The symptom of this is: &prompt.root; ccdconfig -C ccdconfig: ioctl (CCDIOCSET): /dev/ccd0c: Inappropriate file type or format This usually happens when you are trying to concatenate the c partitions, which default to type unused. The ccd driver requires the underlying partition type to be FS_BSDFFS. Edit the disklabel of the disks you are trying to concatenate and change the types of partitions to 4.2BSD. Why can I not edit the disklabel on my ccd? The symptom of this is: &prompt.root; disklabel ccd0 (it prints something sensible here, so let us try to edit it) &prompt.root; disklabel -e ccd0 (edit, save, quit) disklabel: ioctl DIOCWDINFO: No disk label on disk; use "disklabel -r" to install initial label This is because the disklabel returned by ccd is actually a fake one that is not really on the disk. You can solve this problem by writing it back explicitly, as in: &prompt.root; disklabel ccd0 > /tmp/disklabel.tmp &prompt.root; disklabel -Rr ccd0 /tmp/disklabel.tmp &prompt.root; disklabel -e ccd0 (this will work now) Can I mount other foreign filesystems under FreeBSD? Digital UNIX UFS CDROMs can be mounted directly on FreeBSD. Mounting disk partitions from Digital UNIX and other systems that support UFS may be more complex, depending on the details of the disk partitioning for the operating system in question. Linux As of 2.2, FreeBSD supports ext2fs partitions. See &man.mount.ext2fs.8; for more information. NT A read-only NTFS driver exists for FreeBSD. For more information, see this tutorial by Mark Ovens at http://ukug.uk.FreeBSD.org/~mark/ntfs_install.html. Any other information on this subject would be appreciated. How do I mount a secondary DOS partition? The secondary DOS partitions are found after ALL the primary partitions. For example, if you have an E partition as the second DOS partition on the second SCSI drive, you need to create the special files for slice 5 in /dev, then mount /dev/da1s5: &prompt.root; cd /dev &prompt.root; sh MAKEDEV da1s5 &prompt.root; mount -t msdos /dev/da1s5 /dos/e Is there a cryptographic filesystem for &os;? Yes; see the security/cfs port. How can I use the NT loader to boot FreeBSD? This procedure is slightly different for 2.2.x and 3.x (with the 3-stage boot) systems. The general idea is that you copy the first sector of your native root FreeBSD partition into a file in the DOS/NT partition. Assuming you name that file something like c:\bootsect.bsd (inspired by c:\bootsect.dos), you can then edit the c:\boot.ini file to come up with something like this: [boot loader] timeout=30 default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS [operating systems] multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows NT" C:\BOOTSECT.BSD="FreeBSD" C:\="DOS" For 2.2.x systems this procedure assumes that DOS, NT, FreeBSD, or whatever have been installed into their respective fdisk partitions on the same disk. This example was tested on a system where DOS & NT were on the first fdisk partition, and FreeBSD on the second. FreeBSD was also set up to boot from its native partition, not the disk's MBR. Mount a DOS-formatted floppy (if you have converted to NTFS) or the FAT partition, under, say, /mnt. &prompt.root; dd if=/dev/rda0a of=/mnt/bootsect.bsd bs=512 count=1 Reboot into DOS or NT. NTFS users copy the bootsect.bsd and/or the bootsect.lnx file from the floppy to C:\. Modify the attributes (permissions) on boot.ini with: C:\> attrib -s -r c:\boot.ini Edit to add the appropriate entries from the example boot.ini above, and restore the attributes: C:\> attrib +s +r c:\boot.ini If FreeBSD is booting from the MBR, restore it with the DOS fdisk command after you reconfigure them to boot from their native partitions. For FreeBSD 3.x systems the procedure is somewhat simpler. If FreeBSD is installed on the same disk as the NT boot partition simply copy /boot/boot1 to C:\BOOTSECT.BSD However, if FreeBSD is installed on a different disk /boot/boot1 will not work, /boot/boot0 is needed. DO NOT SIMPLY COPY /boot/boot0 INSTEAD OF /boot/boot1, YOU WILL OVERWRITE YOUR PARTITION TABLE AND RENDER YOUR COMPUTER UN-BOOTABLE! /boot/boot0 needs to be installed using sysinstall by selecting the FreeBSD boot manager on the screen which asks if you wish to use a boot manager. This is because /boot/boot0 has the partition table area filled with NULL characters but sysinstall copies the partition table before copying /boot/boot0 to the MBR. When the FreeBSD boot manager runs it records the last OS booted by setting the active flag on the partition table entry for that OS and then writes the whole 512-bytes of itself back to the MBR so if you just copy /boot/boot0 to C:\BOOTSECT.BSD then it writes an empty partition table, with the active flag set on one entry, to the MBR. How do I boot FreeBSD and Linux from LILO? If you have FreeBSD and Linux on the same disk, just follow LILO's installation instructions for booting a non-Linux operating system. Very briefly, these are: Boot Linux, and add the following lines to /etc/lilo.conf: other=/dev/hda2 table=/dev/hda label=FreeBSD (the above assumes that your FreeBSD slice is known to Linux as /dev/hda2; tailor to suit your setup). Then, run lilo as root and you should be done. If FreeBSD resides on another disk, you need to add loader=/boot/chain.b to the LILO entry. For example: other=/dev/dab4 table=/dev/dab loader=/boot/chain.b label=FreeBSD In some cases you may need to specify the BIOS drive number to the FreeBSD boot loader to successfully boot off the second disk. For example, if your FreeBSD SCSI disk is probed by BIOS as BIOS disk 1, at the FreeBSD boot loader prompt you need to specify: Boot: 1:da(0,a)/kernel On FreeBSD 2.2.5 and later, you can configure &man.boot.8; to automatically do this for you at boot time. The Linux+FreeBSD mini-HOWTO is a good reference for FreeBSD and Linux interoperability issues. How do I boot FreeBSD and Linux using BootEasy? Install LILO at the start of your Linux boot partition instead of in the Master Boot Record. You can then boot LILO from BootEasy. If you are running Windows-95 and Linux this is recommended anyway, to make it simpler to get Linux booting again if you should need to reinstall Windows95 (which is a Jealous Operating System, and will bear no other Operating Systems in the Master Boot Record). How do I change the boot prompt from ??? to something more meaningful? You can not do that with the standard boot manager without rewriting it. There are a number of other boot managers in the sysutils ports category that provide this functionality. I have a new removable drive, how do I use it? Whether it is a removable drive like a ZIP or an EZ drive (or even a floppy, if you want to use it that way), or a new hard disk, once it is installed and recognized by the system, and you have your cartridge/floppy/whatever slotted in, things are pretty much the same for all devices. (this section is based on Mark Mayo's ZIP FAQ) If it is a ZIP drive or a floppy, you have already got a DOS filesystem on it, you can use a command like this: &prompt.root; mount -t msdos /dev/fd0c /floppy if it is a floppy, or this: &prompt.root; mount -t msdos /dev/da2s4 /zip for a ZIP disk with the factory configuration. For other disks, see how they are laid out using &man.fdisk.8; or &man.sysinstall.8;. The rest of the examples will be for a ZIP drive on da2, the third SCSI disk. Unless it is a floppy, or a removable you plan on sharing with other people, it is probably a better idea to stick a BSD - file system on it. You will get long filename support, at least a + filesystem on it. You will get long filename support, at least a 2X improvement in performance, and a lot more stability. First, you need to redo the DOS-level partitions/filesystems. You can either use &man.fdisk.8; or /stand/sysinstall, or for a small drive that you do not want to bother with multiple operating system support on, just blow away the whole FAT partition table (slices) and just use the BSD partitioning: &prompt.root; dd if=/dev/zero of=/dev/rda2 count=2 &prompt.root; disklabel -Brw da2 auto You can use disklabel or /stand/sysinstall to create multiple BSD partitions. You will certainly want to do this if you are adding swap space on a fixed disk, but it is probably irrelevant on a removable drive like a ZIP. - Finally, create a new file system, this one is on our ZIP + Finally, create a new filesystem, this one is on our ZIP drive using the whole disk: &prompt.root; newfs /dev/rda2c and mount it: &prompt.root; mount /dev/da2c /zip and it is probably a good idea to add a line like this to /etc/fstab (see &man.fstab.5;) so you can just type mount /zip in the future: /dev/da2c /zip ffs rw,noauto 0 0 Why do I get Incorrect super block when mounting a CDROM? You have to tell &man.mount.8; the type of the device that you want to mount. This is described in the Handbook section on optical media, specifically the section Using Data CDs. Why do I get Device not configured when mounting a CDROM? This generally means that there is no CDROM in the CDROM drive, or the drive is not visible on the bus. Please see the Using Data CDs section of the Handbook for a detailed discussion of this issue. Why do all non-English characters in filenames show up as ? on my CDs when mounted in FreeBSD? Your CDROM probably uses the Joliet extension for storing information about files and directories. This is discussed in the Handbook chapter on creating and using CDROMs, specifically the section on Using Data CDROMs. I burned a CD under FreeBSD and now I can not read it under any other operating system. Why? You most likely burned a raw file to your CD, rather than creating an ISO 9660 filesystem. Take a look at the Handbook chapter on creating CDROMs, particularly the section on burning raw data CDs. How can I create an image of a data CD? This is discussed in the Handbook section on duplicating data CDs. For more on working with CDROMs, see the Creating CDs Section in the Storage chapter in the Handbook. Why can I not mount an audio CD? If you try to mount an audio CD, you will get an error like cd9660: /dev/acd0c: Invalid argument. This is because mount only works on filesystems. Audio CDs do not have filesystems; they just have data. You need a program that reads audio CDs, such as the audio/xmcd port. How do I mount a multi-session CD? By default, &man.mount.8; will attempt to mount the last data track (session) of a CD. If you would like to load an earlier session, you must use the command line argument. Please see &man.mount.cd9660.8; for specific examples. How do I let ordinary users mount floppies, CDROMs and other removable media? Ordinary users can be permitted to mount devices. Here is how: As root set the sysctl variable vfs.usermount to 1. &prompt.root; sysctl -w vfs.usermount=1 As root assign the appropriate permissions to the block device associated with the removable media. For example, to allow users to mount the first floppy drive, use: &prompt.root; chmod 666 /dev/fd0 To allow users in the group operator to mount the CDROM drive, use: &prompt.root; chgrp operator /dev/cd0c &prompt.root; chmod 640 /dev/cd0c Finally, add the line vfs.usermount=1 to the file /etc/sysctl.conf so that it is reset at system boot time. All users can now mount the floppy /dev/fd0 onto a directory that they own: &prompt.user; mkdir ~/my-mount-point &prompt.user; mount -t msdos /dev/fd0 ~/my-mount-point Users in group operator can now mount the CDROM /dev/cd0c onto a directory that they own: &prompt.user; mkdir ~/my-mount-point &prompt.user; mount -t msdos /dev/cd0c ~/my-mount-point Unmounting the device is simple: &prompt.user; umount ~/my-mount-point Enabling vfs.usermount, however, has negative security implications. A better way to access MSDOS formatted media is to use the mtools package in the ports collection. The du and df commands show different amounts of disk space available. What is going on? You need to understand what du and df really do. du goes through the directory tree, measures how large each file is, and presents the totals. df just asks the filesystem how much space it has left. They seem to be the same thing, but a file without a directory entry will affect df but not du. When a program is using a file, and you delete the file, the file is not really removed from the filesystem until the program stops using it. The file is immediately deleted from the directory listing, however. You can see this easily enough with a program such as more. Assume you have a file large enough that its presence affects the output of du and df. (Since disks can be so large today, this might be a very large file!) If you delete this file while using more on it, more does not immediately choke and complain that it cannot view the file. The entry is simply removed from the directory so no other program or user can access it. du shows that it is gone — it has walked the directory tree and the file is not listed. df shows that it is still there, as the filesystem knows that more is still using that space. Once you end the more session, du and df will agree. Note that softupdates can delay the freeing of disk space; you might need to wait up to 30 seconds for the change to be visible! This situation is common on web servers. Many people set up a FreeBSD web server and forget to rotate the log files. The access log fills up /var. The new administrator deletes the file, but the system still complains that the partition is full. Stopping and restarting the web server program would free the file, allowing the system to release the disk space. To prevent this from happening, set up &man.newsyslog.8;. How can I add more swap space? In the Configuration and Tuning section of the Handbook, you will find a section describing how to do this. System Administration Where are the system start-up configuration files? From 2.0.5R to 2.2.1R, the primary configuration file is /etc/sysconfig. All the options are to be specified in this file and other files such as /etc/rc (see &man.rc.8;) and /etc/netstart just include it. Look in the /etc/sysconfig file and change the value to match your system. This file is filled with comments to show what to put in there. In post-2.2.1 and 3.0, /etc/sysconfig was renamed to a more self-describing &man.rc.conf.5; file and the syntax cleaned up a bit in the process. /etc/netstart was also renamed to /etc/rc.network so that all files could be copied with a cp /usr/src/etc/rc* /etc command. And, in 3.1 and later, /etc/rc.conf has been moved to /etc/defaults/rc.conf. Do not edit this file! Instead, if there is any entry in /etc/defaults/rc.conf that you want to change, you should copy the line into /etc/rc.conf and change it there. For example, if you wish to start named, the DNS server included with FreeBSD in FreeBSD 3.1 or later, all you need to do is: &prompt.root; echo named_enable="YES" >> /etc/rc.conf To start up local services in FreeBSD 3.1 or later, place shell scripts in the /usr/local/etc/rc.d directory. These shell scripts should be set executable, and end with a .sh. In FreeBSD 3.0 and earlier releases, you should edit the /etc/rc.local file. The /etc/rc.serial is for serial port initialization (e.g. locking the port characteristics, and so on.). The /etc/rc.i386 is for Intel-specifics settings, such as iBCS2 emulation or the PC system console configuration. How do I add a user easily? Use the &man.adduser.8; command. For more complicated usage, the &man.pw.8; command. To remove the user again, use the &man.rmuser.8; command. Once again, &man.pw.8; will work as well. Why do I keep getting messages like root: not found after editing my crontab file? This is normally caused by editing the system crontab (/etc/crontab) and then using &man.crontab.1; to install it: &prompt.root; crontab /etc/crontab This is not the correct way to do things. The system crontab has a different format to the per-user crontabs which &man.crontab.1; updates (the &man.crontab.5; manual page explains the differences in more detail). If this is what you did, the extra crontab is simply a copy of /etc/crontab in the wrong format it. Delete it with the command: &prompt.root; crontab -r Next time, when you edit /etc/crontab, you should not do anything to inform &man.cron.8; of the changes, since it will notice them automatically. If you want something to be run once per day, week, or month, it is probably better to add shell scripts /usr/local/etc/periodic, and let the &man.periodic.8; command run from the system cron schedule it with the other periodic system tasks. The actual reason for the error is that the system crontab has an extra field, specifying which user to run the command as. In the default system crontab provided with FreeBSD, this is root for all entries. When this crontab is used as the root user's crontab (which is not the same as the system crontab), &man.cron.8; assumes the string root is the first word of the command to execute, but no such command exists. Why do I get the error, you are not in the correct group to su root when I try to su to root? This is a security feature. In order to su to root (or any other account with superuser privileges), you must be in the wheel group. If this feature were not there, anybody with an account on a system who also found out root's password would be able to gain superuser level access to the system. With this feature, this is not strictly true; &man.su.1; will prevent them from even trying to enter the password if they are not in wheel. To allow someone to su to root, simply put them in the wheel group. I made a mistake in rc.conf, or another startup file, and now I cannot edit it because the filesystem is read-only. What should I do? When you get the prompt to enter the shell pathname, simply press ENTER, and run mount / to re-mount the root filesystem in read/write mode. You may also need to run mount -a -t ufs to mount the filesystem where your favourite editor is defined. If your favourite editor is on a network filesystem, you will need to either configure the network manually before you can mount network filesystems, or use an editor which resides on a local filesystem, such as &man.ed.1;. If you intend to use a full screen editor such as &man.vi.1; or &man.emacs.1;, you may also need to run export TERM=cons25 so that these editors can load the correct data from the &man.termcap.5; database. Once you have performed these steps, you can edit /etc/rc.conf as you usually would to fix the syntax error. The error message displayed immediately after the kernel boot messages should tell you the number of the line in the file which is at fault. Why am I having trouble setting up my printer? Please have a look at the Handbook entry on printing. It should cover most of your problem. See the Handbook entry on printing. Some printers require a host-based driver to do any kind of printing. These so-called WinPrinters are not natively supported by FreeBSD. If your printer does not work in DOS or Windows NT 4.0, it is probably a WinPrinter. Your only hope of getting one of these to work is to check if the print/pnm2ppa port supports it. How can I correct the keyboard mappings for my system? Please see the Handbook section on using localization, specifically the section on console setup. Why do I get messages like: unknown: <PNP0303> can't assign resources on boot? The following is an excerpt from a post to the freebsd-current mailing list.
&a.wollman;, 24 April 2001 The can't assign resources messages indicate that the devices are legacy ISA devices for which a non-PnP-aware driver is compiled into the kernel. These include devices such as keyboard controllers, the programmable interrupt controller chip, and several other bits of standard infrastructure. The resources cannot be assigned because there is already a driver using those addresses.
Why can I not get user quotas to work properly? Do not turn on quotas on /, - Put the quota file on the file system that the quotas + Put the quota file on the filesystem that the quotas are to be enforced on. ie: Filesystem Quota file /usr /usr/admin/quotas /home /home/admin/quotas … … Does FreeBSD support System V IPC primitives? Yes, FreeBSD supports System V-style IPC. This includes shared memory, messages and semaphores. You need to add the following lines to your kernel config to enable them. options SYSVSHM # enable shared memory options SYSVSEM # enable for semaphores options SYSVMSG # enable for messaging In FreeBSD 3.2 and later, these options are already part of the GENERIC kernel, which means they should already be compiled into your system. Recompile and install your kernel. How do I use sendmail for mail delivery with UUCP? The sendmail configuration that ships with FreeBSD is suited for sites that connect directly to the Internet. Sites that wish to exchange their mail via UUCP must install another sendmail configuration file. Tweaking /etc/mail/sendmail.cf manually is considered something for purists. Sendmail version 8 comes with a new approach of generating config files via some &man.m4.1; preprocessing, where the actual hand-crafted configuration is on a higher abstraction level. You should use the configuration files under /usr/src/usr.sbin/sendmail/cf. If you did not install your system with full sources, the sendmail config stuff has been broken out into a separate source distribution tarball just for you. Assuming you have got your CDROM mounted, do: &prompt.root; cd /cdrom/src &prompt.root; cat scontrib.?? | tar xzf - -C /usr/src contrib/sendmail Do not panic, this is only a few hundred kilobytes in size. The file README in the cf directory can serve as a basic introduction to m4 configuration. For UUCP delivery, you are best advised to use the mailertable feature. This constitutes a database that sendmail can use to base its routing decision upon. First, you have to create your .mc file. The directory /usr/src/usr.sbin/sendmail/cf/cf is the home of these files. Look around, there are already a few examples. Assuming you have named your file foo.mc, all you need to do in order to convert it into a valid sendmail.cf is: &prompt.root; cd /usr/src/usr.sbin/sendmail/cf/cf &prompt.root; make foo.cf &prompt.root; cp foo.cf /etc/mail/sendmail.cf A typical .mc file might look like: VERSIONID(`Your version number') OSTYPE(bsd4.4) FEATURE(accept_unresolvable_domains) FEATURE(nocanonify) FEATURE(mailertable, `hash -o /etc/mail/mailertable') define(`UUCP_RELAY', your.uucp.relay) define(`UUCP_MAX_SIZE', 200000) define(`confDONT_PROBE_INTERFACES') MAILER(local) MAILER(smtp) MAILER(uucp) Cw your.alias.host.name Cw youruucpnodename.UUCP The lines containing accept_unresolvable_domains, nocanonify, and confDONT_PROBE_INTERFACES features will prevent any usage of the DNS during mail delivery. The UUCP_RELAY clause is needed for bizarre reasons, do not ask. Simply put an Internet hostname there that is able to handle .UUCP pseudo-domain addresses; most likely, you will enter the mail relay of your ISP there. Once you have got this, you need this file called /etc/mail/mailertable. If you have only one link to the outside that is used for all your mails, the following file will be enough: # # makemap hash /etc/mail/mailertable.db < /etc/mail/mailertable . uucp-dom:your.uucp.relay A more complex example might look like this: # # makemap hash /etc/mail/mailertable.db < /etc/mail/mailertable # horus.interface-business.de uucp-dom:horus .interface-business.de uucp-dom:if-bus interface-business.de uucp-dom:if-bus .heep.sax.de smtp8:%1 horus.UUCP uucp-dom:horus if-bus.UUCP uucp-dom:if-bus . uucp-dom: As you can see, this is part of a real-life file. The first three lines handle special cases where domain-addressed mail should not be sent out to the default route, but instead to some UUCP neighbor in order to shortcut the delivery path. The next line handles mail to the local Ethernet domain that can be delivered using SMTP. Finally, the UUCP neighbors are mentioned in the .UUCP pseudo-domain notation, to allow for a uucp-neighbor !recipient override of the default rules. The last line is always a single dot, matching everything else, with UUCP delivery to a UUCP neighbor that serves as your universal mail gateway to the world. All of the node names behind the uucp-dom: keyword must be valid UUCP neighbors, as you can verify using the command uuname. As a reminder that this file needs to be converted into a DBM database file before being usable, the command line to accomplish this is best placed as a comment at the top of the mailertable. You always have to execute this command each time you change your mailertable. Final hint: if you are uncertain whether some particular mail routing would work, remember the option to sendmail. It starts sendmail in address test mode; simply enter 3,0, followed by the address you wish to test for the mail routing. The last line tells you the used internal mail agent, the destination host this agent will be called with, and the (possibly translated) address. Leave this mode by typing Control-D. &prompt.user; sendmail -bt ADDRESS TEST MODE (ruleset 3 NOT automatically invoked) Enter <ruleset> <address> > 3,0 foo@example.com canonify input: foo @ example . com ... parse returns: $# uucp-dom $@ your.uucp.relay $: foo < @ example . com . > > ^D How do I set up mail with a dialup connection to the 'net? If you have got a statically assigned IP number, you should not need to adjust anything from the default. Set your host name up as your assigned Internet name and sendmail will do the rest. If you have got a dynamically assigned IP number and use a dialup PPP connection to the Internet, you will probably be given a mailbox on your ISPs mail server. Lets assume your ISPs domain is example.net, and that your user name is user. Lets also assume you have called your machine bsd.home and that your ISP has told you that you may use relay.example.net as a mail relay. In order to retrieve mail from your mailbox, you will need to install a retrieval agent. Fetchmail is a good choice as it supports many different protocols. Usually, POP3 will be provided by your ISP. If you have chosen to use user-PPP, you can automatically fetch your mail when a connection to the 'net is established with the following entry in /etc/ppp/ppp.linkup: MYADDR: !bg su user -c fetchmail If you are using sendmail (as shown below) to deliver mail to non-local accounts, put the command !bg su user -c "sendmail -q" after the above shown entry. This forces sendmail to process your mailqueue as soon as the connection to the 'net is established. I am assuming that you have an account for user on bsd.home. In the home directory of user on bsd.home, create a .fetchmailrc file: poll example.net protocol pop3 fetchall pass MySecret This file should not be readable by anyone except user as it contains the password MySecret. In order to send mail with the correct from: header, you must tell sendmail to use user@example.net rather than user@bsd.home. You may also wish to tell sendmail to send all mail via relay.example.net, allowing quicker mail transmission. The following .mc file should suffice: VERSIONID(`bsd.home.mc version 1.0') OSTYPE(bsd4.4)dnl FEATURE(nouucp)dnl MAILER(local)dnl MAILER(smtp)dnl Cwlocalhost Cwbsd.home MASQUERADE_AS(`example.net')dnl FEATURE(allmasquerade)dnl FEATURE(masquerade_envelope)dnl FEATURE(nocanonify)dnl FEATURE(nodns)dnl define(`SMART_HOST', `relay.example.net') Dmbsd.home define(`confDOMAIN_NAME',`bsd.home')dnl define(`confDELIVERY_MODE',`deferred')dnl Refer to the previous section for details of how to turn this .mc file into a sendmail.cf file. Also, do not forget to restart sendmail after updating sendmail.cf. What other mail-server software can I use, instead of Sendmail? Sendmail is the default mail-server software for FreeBSD, but you can easily replace it with one of the other MTA (for instance, an MTA installed from the ports). There are various alternative MTA's in the ports tree already, with mail/exim, mail/postfix, mail/qmail, mail/zmailer, being some of the most popular choices. Diversity is nice, and the fact that you have many different mail-servers to chose from is considered a good thing; therefore try to avoid asking questions like Is Sendmail better than Qmail? in the mailing lists. If you do feel like asking, first check the mailing list archives. The advantages and disadvantages of each and every one of the available MTA's have already been discussed a few times. I have forgotten the root password! What do I do? Do not Panic! Simply restart the system, type boot -s at the Boot: prompt (just -s for FreeBSD releases before 3.2) to enter Single User mode. At the question about the shell to use, hit ENTER. You will be dropped to a &prompt.root; prompt. Enter mount -u / to remount your root filesystem read/write, then run mount -a to remount all the filesystems. Run passwd root to change the root password then run &man.exit.1; to continue booting. How do I keep Control-Alt-Delete from rebooting the system? If you are using syscons (the default console driver) in FreeBSD 2.2.7-RELEASE or later, build and install a new kernel with the line options SC_DISABLE_REBOOT in the configuration file. If you use the PCVT console driver in FreeBSD 2.2.5-RELEASE or later, use the following kernel configuration line instead: options PCVT_CTRL_ALT_DEL For older versions of FreeBSD, edit the keymap you are using for the console and replace the boot keywords with nop. The default keymap is /usr/share/syscons/keymaps/us.iso.kbd. You may have to instruct /etc/rc.conf to load this keymap explicitly for the change to take effect. Of course if you are using an alternate keymap for your country, you should edit that one instead. How do I reformat DOS text files to Unix ones? Simply use this perl command: &prompt.user; perl -i.bak -npe 's/\r\n/\n/g' file ... file is the file(s) to process. The modification is done in-place, with the original file stored with a .bak extension. Alternatively you can use the &man.tr.1; command: &prompt.user; tr -d '\r' < dos-text-file > unix-file dos-text-file is the file containing DOS text while unix-file will contain the converted output. This can be quite a bit faster than using perl. How do I kill processes by name? Use &man.killall.1;. Why is su bugging me about not being in root's ACL? The error comes from the Kerberos distributed authentication system. The problem is not fatal but annoying. You can either run su with the -K option, or uninstall Kerberos as described in the next question. How do I uninstall Kerberos? To remove Kerberos from the system, reinstall the bin distribution for the release you are running. If you have the CDROM, you can mount the cd (we will assume on /cdrom) and run &prompt.root; cd /cdrom/bin &prompt.root; ./install.sh Alternately, you can remove all "MAKE_KERBEROS" options from /etc/make.conf and rebuild world. How do I add pseudoterminals to the system? If you have lots of telnet, ssh, X, or screen users, you will probably run out of pseudoterminals. Here is how to add more: Build and install a new kernel with the line pseudo-device pty 256 in the configuration file. Run the commands &prompt.root; cd /dev &prompt.root; sh MAKEDEV pty{1,2,3,4,5,6,7} to make 256 device nodes for the new terminals. Edit /etc/ttys and add lines for each of the 256 terminals. They should match the form of the existing entries, i.e. they look like ttyqc none network The order of the letter designations is tty[pqrsPQRS][0-9a-v], using a regular expression. Reboot the system with the new kernel and you are ready to go. Why can I not create the snd0 device? There is no snd device. The name is used as a shorthand for the various devices that make up the FreeBSD sound driver, such as mixer, sequencer, and dsp. To create these devices you should &prompt.root; cd /dev &prompt.root; sh MAKEDEV snd0 How do I re-read /etc/rc.conf and re-start /etc/rc without a reboot? Go into single user mode and then back to multi user mode. On the console do: &prompt.root; shutdown now (Note: without -r or -h) &prompt.root; return &prompt.root; exit What is a sandbox? Sandbox is a security term. It can mean two things: A process which is placed inside a set of virtual walls that are designed to prevent someone who breaks into the process from being able to break into the wider system. The process is said to be able to play inside the walls. That is, nothing the process does in regards to executing code is supposed to be able to breech the walls so you do not have to do a detailed audit of its code to be able to say certain things about its security. The walls might be a userid, for example. This is the definition used in the security and named man pages. Take the ntalk service, for example (see /etc/inetd.conf). This service used to run as userid root. Now it runs as userid tty. The tty user is a sandbox designed to make it more difficult for someone who has successfully hacked into the system via ntalk from being able to hack beyond that user id. A process which is placed inside a simulation of the machine. This is more hard-core. Basically it means that someone who is able to break into the process may believe that he can break into the wider machine but is, in fact, only breaking into a simulation of that machine and not modifying any real data. The most common way to accomplish this is to build a simulated environment in a subdirectory and then run the processes in that directory chroot'd (i.e. / for that process is this directory, not the real / of the system). Another common use is to mount an underlying filesystem read-only and then create a filesystem layer on top of it that gives a process a seemingly writeable view into that filesystem. The process may believe it is able to write to those files, but only the process sees the effects - other processes in the system do not, necessarily. An attempt is made to make this sort of sandbox so transparent that the user (or hacker) does not realize that he is sitting in it. Unix implements two core sandboxes. One is at the process level, and one is at the userid level. Every Unix process is completely firewalled off from every other Unix process. One process cannot modify the address space of another. This is unlike Windows where a process can easily overwrite the address space of any other, leading to a crash. A Unix process is owned by a particular userid. If the userid is not the root user, it serves to firewall the process off from processes owned by other users. The userid is also used to firewall off on-disk data. What is securelevel? The securelevel is a security mechanism implemented in the kernel. Basically, when the securelevel is positive, the kernel restricts certain tasks; not even the superuser (i.e., root) is allowed to do them. At the time of this writing, the securelevel mechanism is capable of, among other things, limiting the ability to, unset certain file flags, such as schg (the system immutable flag), write to kernel memory via /dev/mem and /dev/kmem, load kernel modules, and alter &man.ipfirewall.4; rules. To check the status of the securelevel on a running system, simply execute the following command: &prompt.root; sysctl kern.securelevel The output will contain the name of the &man.sysctl.8; variable (in this case, kern.securelevel) and a number. The latter is the current value of the securelevel. If it is positive (i.e., greater than 0), at least some of the securelevel's protections are enabled. You cannot lower the securelevel of a running system; being able to do that would defeat its purpose. If you need to do a task that requires that the securelevel be non-positive (e.g., an installworld or changing the date), you will have to change the securelevel setting in /etc/rc.conf (you want to look for the kern_securelevel and kern_securelevel_enable variables) and reboot. For more information on securelevel and the specific things all the levels do, please consult the &man.init.8; manual page. Securelevel is not a silver bullet; it has many known deficiencies. More often than not, it provides a false sense of security. One of its biggest problems is that in order for it to be at all effective, all files used in the boot process up until the securelevel is set must be protected. If an attacker can get the system to execute their code prior to the securelevel being set (which happens quite late in the boot process since some things the system must do at start-up cannot be done at an elevated securelevel), its protections are invalidated. While this task of protecting all files used in the boot process is not technically impossible, if it is achieved, system maintenance will become a nightmare since one would have to take the system down, at least to single-user mode, to modify a configuration file. This point and others are often discussed on the mailing lists, particularly freebsd-security. Please search the archives here for an extensive discussion. Some people are hopeful that securelevel will soon go away in favor of a more fine-grained mechanism, but things are still hazy in this respect. Consider yourself warned. I tried to update my system to the latest -STABLE, but got -RC or -PRERELEASE! What is going on? Short answer: it is just a name. RC stands for Release Candidate. It signifies that a release is imminent. In FreeBSD, -PRERELEASE is typically synonymous with the code freeze before a release. (For some releases, the -BETA label was used in the same way as -PRERELEASE.) Long answer: FreeBSD derives its releases from one of two places. Major, dot-zero, releases, such as 3.0-RELEASE and 4.0-RELEASE, are branched from the head of the development stream, commonly referred to as -CURRENT. Minor releases, such as 3.1-RELEASE or 4.2-RELEASE, have been snapshots of the active -STABLE branch. Starting with 4.3-RELEASE, each release also now has its own branch which can be tracked by people requiring an extremely conservative rate of development (typically only security advisories). When a release is about to be made, the branch from which it will be derived from has to undergo a certain process. Part of this process is a code freeze. When a code freeze is initiated, the name of the branch is changed to reflect that it is about to become a release. For example, if the branch used to be called 4.5-STABLE, its name will be changed to 4.6-PRERELEASE to signify the code freeze and signify that extra pre-release testing should be happening. Bug fixes can still be committed to be part of the release. When the source code is in shape for the release the name will be changed to 4.6-RC to signify that a release is about to be made from it. Once in the RC stage, only the most critical bugs found can be fixed. Once the release (4.6-RELEASE in this example) and release branch have been made, the branch will be renamed to 4.6-STABLE. For more information on version numbers and the various CVS branches, refer to the Release Engineering article. I tried to install a new kernel, and the chflags failed. How do I get around this? Short answer: You are probably at security level greater than 0. Reboot directly to single user mode to install the kernel. Long answer: FreeBSD disallows changing system flags at security levels greater than 0. You can check your security level with the command: &prompt.root; sysctl kern.securelevel You cannot lower the security level; you have to boot to single mode to install the kernel, or change the security level in /etc/rc.conf then reboot. See the &man.init.8; man page for details on securelevel, and see /etc/defaults/rc.conf and the &man.rc.conf.5; man page for more information on rc.conf. I cannot change the time on my system by more than one second! How do I get around this? Short answer: You are probably at security level greater than 1. Reboot directly to single user mode to change the date. Long answer: FreeBSD disallows changing the time by more that one second at security levels greater than 1. You can check your security level with the command: &prompt.root; sysctl kern.securelevel You cannot lower the security level; you have to boot to single mode to change the date, or change the security level in /etc/rc.conf then reboot. See the &man.init.8; man page for details on securelevel, and see /etc/defaults/rc.conf and the &man.rc.conf.5; man page for more information on rc.conf. Why is rpc.statd using 256 megabytes of memory? No, there is no memory leak, and it is not using 256 Mbytes of memory. It simply likes to (i.e., always does) map an obscene amount of memory into its address space for convenience. There is nothing terribly wrong with this from a technical standpoint; it just throws off things like &man.top.1; and &man.ps.1;. &man.rpc.statd.8; maps its status file (resident on /var) into its address space; to save worrying about remapping it later when it needs to grow, it maps it with a generous size. This is very evident from the source code, where one can see that the length argument to &man.mmap.2; is 0x10000000, or one sixteenth of the address space on an IA32, or exactly 256MB. Why can I not unset the schg file flag? You are running at an elevated (i.e., greater than 0) securelevel. Lower the securelevel and try again. For more information, see the FAQ entry on securelevel and the &man.init.8; manual page. Why does SSH authentication through .shosts not work by default in recent versions of FreeBSD? The reason why .shosts authentication does not work by default in more recent versions of FreeBSD is because &man.ssh.1; is not installed suid root by default. To fix this, you can do one of the following: As a permanent fix, set ENABLE_SUID_SSH to true in /etc/make.conf and rebuild ssh (or run make world). As a temporary fix, change the mode on /usr/bin/ssh to 4555 by running chmod 4755 /usr/bin/ssh as root. Then add ENABLE_SUID_SSH= true to /etc/make.conf so the change takes effect the next time make world is run. What is vnlru? vnlru flushes and frees vnodes when the system hits the kern.maxvnodes limit. This kernel thread sits mostly idle, and only activates if you have a huge amount of RAM and are accessing tens of thousands of tiny files. The X Window System and Virtual Consoles I want to run X, how do I go about it? The easiest way is to simply specify that you want to run X during the installation process. Then read and follow the documentation on the xf86config tool, which assists you in configuring XFree86 for your particular graphics card/mouse/etc. You may also wish to investigate the Xaccel server. See the section on Xi Graphics or Metro Link for more details. I tried to run X, but I get an KDENABIO failed (Operation not permitted) error when I type startx. What do I do now? Your system is running at a raised securelevel, is not it? It is, indeed, impossible to start X at a raised securelevel. To see why, look at the &man.init.8; man page. So the question is what else you should do instead, and you basically have two choices: set your securelevel back down to zero (usually from /etc/rc.conf), or run &man.xdm.1; at boot time (before the securelevel is raised). See for more information about running &man.xdm.1; at boot time. Why does my mouse not work with X? If you are using syscons (the default console driver), you can configure FreeBSD to support a mouse pointer on each virtual screen. In order to avoid conflicting with X, syscons supports a virtual device called /dev/sysmouse. All mouse events received from the real mouse device are written to the sysmouse device via moused. If you wish to use your mouse on one or more virtual consoles, and use X, see and set up moused. Then edit /etc/XF86Config and make sure you have the following lines. Section Pointer Protocol "SysMouse" Device "/dev/sysmouse" ..... The above example is for XFree86 3.3.2 or later. For earlier versions, the Protocol should be MouseSystems. Some people prefer to use /dev/mouse under X. To make this work, /dev/mouse should be linked to /dev/sysmouse (see &man.sysmouse.4;): &prompt.root; cd /dev &prompt.root; rm -f mouse &prompt.root; ln -s sysmouse mouse My mouse has a fancy wheel. Can I use it in X? Yes. But you need to customize X client programs. See Colas Nahaboo's web page (http://www.inria.fr/koala/colas/mouse-wheel-scroll/) . If you want to use the imwheel program, just follow these simple steps. Translate the Wheel Events The imwheel program works by translating mouse button 4 and mouse button 5 events into key events. Thus, you have to get the mouse driver to translate mouse wheel events to button 4 and 5 events. There are two ways of doing this, the first way is to have &man.moused.8; do the translation. The second way is for the X server itself to do the event translation. Using &man.moused.8; to Translate Wheel Events To have &man.moused.8; perform the event translations, simply add to the command line used to start &man.moused.8;. For example, if you normally start &man.moused.8; via moused -p /dev/psm0 you would start it by entering moused -p /dev/psm0 -z 4 instead. If you start &man.moused.8; automatically during bootup via /etc/rc.conf, you can simply add to the moused_flags variable in /etc/rc.conf. You now need to tell X that you have a 5 button mouse. To do this, simply add the line Buttons 5 to the Pointer section of /etc/XF86Config. For example, you might have the following Pointer section in /etc/XF86Config. <quote>Pointer</quote> Section for Wheeled Mouse in XFree86 3.3.x series XF86Config with moused Translation Section "Pointer" Protocol "SysMouse" Device "/dev/sysmouse" Buttons 5 EndSection <quote>InputDevice</quote> Section for Wheeled Mouse in XFree86 4.x series XF86Config with X Server Translation Section "InputDevice" Identifier "Mouse1" Driver "mouse" Option "Protocol" "auto" Option "Device" "/dev/sysmouse" Option "Buttons" "5" EndSection <quote>.emacs</quote> example for naive page scrolling with Wheeled Mouse ;; wheel mouse (global-set-key [mouse-4] 'scroll-down) (global-set-key [mouse-5] 'scroll-up) Using Your X Server to Translate the Wheel Events If you are not running &man.moused.8;, or if you do not want &man.moused.8; to translate your wheel events, you can have the X server do the event translation instead. This requires a couple of modifications to your /etc/XF86Config file. First, you need to choose the proper protocol for your mouse. Most wheeled mice use the IntelliMouse protocol. However, XFree86 does support other protocols, such as MouseManPlusPS/2 for the Logitech MouseMan+ mice. Once you have chosen the protocol you will use, you need to add a Protocol line to the Pointer section. Secondly, you need to tell the X server to remap wheel scroll events to mouse buttons 4 and 5. This is done with the ZAxisMapping option. For example, if you are not using &man.moused.8;, and you have an IntelliMouse attached to the PS/2 mouse port you would use the following in /etc/XF86Config. <quote>Pointer</quote> Section for Wheeled Mouse in <filename>XF86Config</filename> with X Server Translation Section "Pointer" Protocol "IntelliMouse" Device "/dev/psm0" ZAxisMapping 4 5 EndSection <quote>InputDevice</quote> Section for Wheeled Mouse in XFree86 4.x series XF86Config with X Server Translation Section "InputDevice" Identifier "Mouse1" Driver "mouse" Option "Protocol" "auto" Option "Device" "/dev/psm0" Option "ZAxisMapping" "4 5" EndSection <quote>.emacs</quote> example for naive page scrolling with Wheeled Mouse ;; wheel mouse (global-set-key [mouse-4] 'scroll-down) (global-set-key [mouse-5] 'scroll-up) Install imwheel Next, install imwheel from the Ports collection. It can be found in the x11 category. This program will map the wheel events from your mouse into keyboard events. For example, it might send Page Up to a program when you scroll the wheel forwards. Imwheel uses a configuration file to map the wheel events to key presses so that it can send different keys to different applications. The default imwheel configuration file is installed in /usr/X11R6/etc/imwheelrc. You can copy it to ~/.imwheelrc and then edit it if you wish to customize imwheel's configuration. The format of the configuration file is documented in &man.imwheel.1;. Configure Emacs to Work with Imwheel (optional) If you use emacs or Xemacs, then you need to add a small section to your ~/.emacs file. For emacs, add the following: <application>Emacs</application> Configuration for <application>Imwheel</application> ;;; For imwheel (setq imwheel-scroll-interval 3) (defun imwheel-scroll-down-some-lines () (interactive) (scroll-down imwheel-scroll-interval)) (defun imwheel-scroll-up-some-lines () (interactive) (scroll-up imwheel-scroll-interval)) (global-set-key [?\M-\C-\)] 'imwheel-scroll-up-some-lines) (global-set-key [?\M-\C-\(] 'imwheel-scroll-down-some-lines) ;;; end imwheel section For Xemacs, add the following to your ~/.emacs file instead: <application>Xemacs</application> Configuration for <application>Imwheel</application> ;;; For imwheel (setq imwheel-scroll-interval 3) (defun imwheel-scroll-down-some-lines () (interactive) (scroll-down imwheel-scroll-interval)) (defun imwheel-scroll-up-some-lines () (interactive) (scroll-up imwheel-scroll-interval)) (define-key global-map [(control meta \))] 'imwheel-scroll-up-some-lines) (define-key global-map [(control meta \()] 'imwheel-scroll-down-some-lines) ;;; end imwheel section Run Imwheel You can just type imwheel in an xterm to start it up once it is installed. It will background itself and take effect immediately. If you want to always use imwheel, simply add it to your .xinitrc or .xsession file. You can safely ignore any warnings imwheel displays about PID files. Those warnings only apply to the Linux version of imwheel. Why do X Window menus and dialog boxes not work right? Try turning off the Num Lock key. If your Num Lock key is on by default at boot-time, you may add the following line in the Keyboard section of the XF86Config file. # Let the server do the NumLock processing. This should only be # required when using pre-R6 clients ServerNumLock What is a virtual console and how do I make more? Virtual consoles, put simply, enable you to have several simultaneous sessions on the same machine without doing anything complicated like setting up a network or running X. When the system starts, it will display a login prompt on the monitor after displaying all the boot messages. You can then type in your login name and password and start working (or playing!) on the first virtual console. At some point, you will probably wish to start another session, perhaps to look at documentation for a program you are running or to read your mail while waiting for an FTP transfer to finish. Just do Alt-F2 (hold down the Alt key and press the F2 key), and you will find a login prompt waiting for you on the second virtual console! When you want to go back to the original session, do Alt-F1. The default FreeBSD installation has three virtual consoles enabled (8 starting with 3.3-RELEASE), and Alt-F1, Alt-F2, and Alt-F3 will switch between these virtual consoles. To enable more of them, edit /etc/ttys (see &man.ttys.5;) and add entries for ttyv4 to ttyvc after the comment on Virtual terminals: # Edit the existing entry for ttyv3 in /etc/ttys and change # "off" to "on". ttyv3 "/usr/libexec/getty Pc" cons25 on secure ttyv4 "/usr/libexec/getty Pc" cons25 on secure ttyv5 "/usr/libexec/getty Pc" cons25 on secure ttyv6 "/usr/libexec/getty Pc" cons25 on secure ttyv7 "/usr/libexec/getty Pc" cons25 on secure ttyv8 "/usr/libexec/getty Pc" cons25 on secure ttyv9 "/usr/libexec/getty Pc" cons25 on secure ttyva "/usr/libexec/getty Pc" cons25 on secure ttyvb "/usr/libexec/getty Pc" cons25 on secure Use as many or as few as you want. The more virtual terminals you have, the more resources that are used; this can be important if you have 8MB RAM or less. You may also want to change the secure to insecure. If you want to run an X server you must leave at least one virtual terminal unused (or turned off) for it to use. That is to say that if you want to have a login prompt pop up for all twelve of your Alt-function keys, you are out of luck - you can only do this for eleven of them if you also want to run an X server on the same machine. The easiest way to disable a console is by turning it off. For example, if you had the full 12 terminal allocation mentioned above and you wanted to run X, you would change settings for virtual terminal 12 from: ttyvb "/usr/libexec/getty Pc" cons25 on secure to: ttyvb "/usr/libexec/getty Pc" cons25 off secure If your keyboard has only ten function keys, you would end up with: ttyv9 "/usr/libexec/getty Pc" cons25 off secure ttyva "/usr/libexec/getty Pc" cons25 off secure ttyvb "/usr/libexec/getty Pc" cons25 off secure (You could also just delete these lines.) Once you have edited /etc/ttys, the next step is to make sure that you have enough virtual terminal devices. The easiest way to do this is: &prompt.root; cd /dev &prompt.root; sh MAKEDEV vty12 Next, the easiest (and cleanest) way to activate the virtual consoles is to reboot. However, if you really do not want to reboot, you can just shut down the X Window system and execute (as root): &prompt.root; kill -HUP 1 It is imperative that you completely shut down X Window if it is running, before running this command. If you do not, your system will probably appear to hang/lock up after executing the kill command. How do I access the virtual consoles from X? Use Ctrl Alt Fn to switch back to a virtual console. Ctrl Alt F1 would return you to the first virtual console. Once you are back to a text console, you can then use Alt Fn as normal to move between them. To return to the X session, you must switch to the virtual console running X. If you invoked X from the command line, (e.g., using startx) then the X session will attach to the next unused virtual console, not the text console from which it was invoked. If you have eight active virtual terminals then X will be running on the ninth, and you would use Alt F9 to return. How do I start XDM on boot? There are two schools of thought on how to start xdm. One school starts xdm from /etc/ttys (see &man.ttys.5;) using the supplied example, while the other simply runs xdm from rc.local (see &man.rc.8;) or from a X.sh script in /usr/local/etc/rc.d. Both are equally valid, and one may work in situations where the other does not. In both cases the result is the same: X will pop up a graphical login: prompt. The ttys method has the advantage of documenting which vty X will start on and passing the responsibility of restarting the X server on logout to init. The rc.local method makes it easy to kill xdm if there is a problem starting the X server. If loaded from rc.local, xdm should be started without any arguments (i.e., as a daemon). xdm must start AFTER getty runs, or else getty and xdm will conflict, locking out the console. The best way around this is to have the script sleep 10 seconds or so then launch xdm. If you are to start xdm from /etc/ttys, there still is a chance of conflict between xdm and &man.getty.8;. One way to avoid this is to add the vt number in the /usr/X11R6/lib/X11/xdm/Xservers file. :0 local /usr/X11R6/bin/X vt4 The above example will direct the X server to run in /dev/ttyv3. Note the number is offset by one. The X server counts the vty from one, whereas the FreeBSD kernel numbers the vty from zero. Why do I get Couldn't open console when I run xconsole? If you start X with startx, the permissions on /dev/console will not get changed, resulting in things like xterm -C and xconsole not working. This is because of the way console permissions are set by default. On a multi-user system, one does not necessarily want just any user to be able to write on the system console. For users who are logging directly onto a machine with a VTY, the &man.fbtab.5; file exists to solve such problems. In a nutshell, make sure an uncommented line of the form /dev/ttyv0 0600 /dev/console is in /etc/fbtab (see &man.fbtab.5;) and it will ensure that whomever logs in on /dev/ttyv0 will own the console. Before, I was able to run XFree86 as a regular user. Why does it now say that I must be root? All X servers need to be run as root in order to get direct access to your video hardware. Older versions of XFree86 (<= 3.3.6) installed all bundled servers to be automatically run as root (setuid to root). This is obviously a security hazard because X servers are large, complicated programs. Newer versions of XFree86 do not install the servers setuid to root for just this reason. Obviously, running an X server as the root user is not acceptable, nor a good idea security-wise. There are two ways to be able to use X as a regular user. The first is to use xdm or another display manager (e.g., kdm); the second is to use the Xwrapper. xdm is a daemon that handles graphical logins. It is usually started at boot time, and is responsible for authenticating users and starting their sessions; it is essentially the graphical counterpart of &man.getty.8; and &man.login.1;. For more information on xdm see the XFree86 documentation, and the the FAQ entry on it. Xwrapper is the X server wrapper; it is a small utility to enable one to manually run an X server while maintaining reasonable safety. It performs some sanity checks on the command line arguments given, and if they pass, runs the appropriate X server. If you do not want to run a display manger for whatever reason, this is for you. If you have installed the complete ports collection, you can find the port in /usr/ports/x11/wrapper. Why does my PS/2 mouse misbehave under X? Your mouse and the mouse driver may have somewhat become out of synchronization. In versions 2.2.5 and earlier, switching away from X to a virtual terminal and getting back to X again may make them re-synchronized. If the problem occurs often, you may add the following option in your kernel configuration file and recompile it. options PSM_CHECKSYNC See the section on building a kernel if you have no experience with building kernels. With this option, there should be less chance of synchronization problem between the mouse and the driver. If, however, you still see the problem, click any mouse button while holding the mouse still to re-synchronize the mouse and the driver. Note that unfortunately this option may not work with all the systems and voids the tap feature of the ALPS GlidePoint device attached to the PS/2 mouse port. In versions 2.2.6 and later, synchronization check is done in a slightly better way and is standard in the PS/2 mouse driver. It should even work with GlidePoint. (As the check code has become a standard feature, PSM_CHECKSYNC option is not available in these versions.) However, in rare case the driver may erroneously report synchronization problem and you may see the kernel message: psmintr: out of sync (xxxx != yyyy) and find your mouse does not seem to work properly. If this happens, disable the synchronization check code by setting the driver flags for the PS/2 mouse driver to 0x100. Enter UserConfig by giving the option at the boot prompt: boot: -c Then, in the UserConfig command line, type: UserConfig> flags psm0 0x100 UserConfig> quit Why does my PS/2 mouse from MouseSystems not work? There have been some reports that certain model of PS/2 mouse from MouseSystems works only if it is put into the high resolution mode. Otherwise, the mouse cursor may jump to the upper-left corner of the screen every so often. Unfortunately there is no workaround for versions 2.0.X and 2.1.X. In versions 2.2 through 2.2.5, apply the following patch to /sys/i386/isa/psm.c and rebuild the kernel. See the section on building a kernel if you have no experience with building kernels. @@ -766,6 +766,8 @@ if (verbose >= 2) log(LOG_DEBUG, "psm%d: SET_DEFAULTS return code:%04x\n", unit, i); + set_mouse_resolution(sc->kbdc, PSMD_RES_HIGH); + #if 0 set_mouse_scaling(sc->kbdc); /* 1:1 scaling */ set_mouse_mode(sc->kbdc); /* stream mode */ In versions 2.2.6 or later, specify the flags 0x04 to the PS/2 mouse driver to put the mouse into the high resolution mode. Enter UserConfig by giving the option at the boot prompt: boot: -c Then, in the UserConfig command line, type: UserConfig> flags psm0 0x04 UserConfig> quit See the previous section for another possible cause of mouse problems. When building an X app, imake cannot find Imake.tmpl. Where is it? Imake.tmpl is part of the Imake package, a standard X application building tool. Imake.tmpl, as well as several header files that are required to build X apps, is contained in the X prog distribution. You can install this from sysinstall or manually from the X distribution files. An X app I am building depends on XFree86 3.3.x, but I have XFree86 4.x installed. What should I do? To tell the port build to link to the XFree86 4.x libraries, add the following to /etc/make.conf, (if you do not have this file, create it): XFREE86_VERSION= 4 How do I reverse the mouse buttons? Run the command xmodmap -e "pointer = 3 2 1" from your .xinitrc or .xsession. How do I install a splash screen and where do I find them? Just prior to the release of FreeBSD 3.1, a new feature was added to allow the display of splash screens during the boot messages. The splash screens currently must be a 256 color bitmap (*.BMP) or ZSoft PCX (*.PCX) file. In addition, they must have a resolution of 320x200 or less to work on standard VGA adapters. If you compile VESA support into your kernel, then you can use larger bitmaps up to 1024x768. Note that VESA support requires the VM86 kernel option to be compiled into the kernel. The actual VESA support can either be compiled directly into the kernel with the VESA kernel config option or by loading the VESA kld module during bootup. To use a splash screen, you need to modify the startup files that control the boot process for FreeBSD. The files for this changed prior to the release of FreeBSD 3.2, so there are now two ways of loading a splash screen: FreeBSD 3.1 The first step is to find a bitmap version of your splash screen. Release 3.1 only supports Windows bitmap splash screens. Once you have found your splash screen of choice copy it to /boot/splash.bmp. Next, you need to have a /boot/loader.rc file that contains the following lines: load kernel load -t splash_image_data /boot/splash.bmp load splash_bmp autoboot FreeBSD 3.2+ In addition to adding support for PCX splash screens, FreeBSD 3.2 includes a nicer way of configuring the boot process. If you wish, you can use the method listed above for FreeBSD 3.1. If you do and you want to use PCX, replace splash_bmp with splash_pcx. If, on the other hand, you want to use the newer boot configuration, you need to create a /boot/loader.rc file that contains the following lines: include /boot/loader.4th start and a /boot/loader.conf that contains the following: splash_bmp_load="YES" bitmap_load="YES" This assumes you are using /boot/splash.bmp for your splash screen. If you would rather use a PCX file, copy it to /boot/splash.pcx, create a /boot/loader.rc as instructed above, and create a /boot/loader.conf that contains: splash_pcx_load="YES" bitmap_load="YES" bitmap_name="/boot/splash.pcx" Now all you need is a splash screen. For that you can surf on over to the gallery at http://www.baldwin.cx/splash/. Can I use the Windows keys on my keyboard in X? Yes. All you need to do is use &man.xmodmap.1; to define what function you wish them to perform. Assuming all Windows keyboards are standard then the keycodes for the 3 keys are 115 - Windows key, between the left-hand Ctrl and Alt keys 116 - Windows key, to the right of the Alt-Gr key 117 - Menu key, to the left of the right-hand Ctrl key To have the left Windows key print a comma, try this. &prompt.root; xmodmap -e "keycode 115 = comma" You will probably have to re-start your window manager to see the result. To have the Windows key-mappings enabled automatically every time you start X either put the xmodmap commands in your ~/.xinitrc file or, preferably, create a file ~/.xmodmaprc and include the xmodmap options, one per line, then add the line xmodmap $HOME/.xmodmaprc to your ~/.xinitrc. For example, you could map the 3 keys top be F13, F14, and F15, respectively. This would make it easy to map them to useful functions within applications or your window manager, as demonstrated further down. To do this put the following in ~/.xmodmaprc. keycode 115 = F13 keycode 116 = F14 keycode 117 = F15 If you use fvwm2, for example, you could map the keys so that F13 iconifies (or de-iconifies) the window the cursor is in, F14 brings the window the cursor is in to the front or, if it is already at the front, pushes it to the back, and F15 pops up the main Workplace (application) menu even if the cursor is not on the desktop, which is useful if you do not have any part of the desktop visible (and the logo on the key matches its functionality). The following entries in ~/.fvwmrc implement the aforementioned setup: Key F13 FTIWS A Iconify Key F14 FTIWS A RaiseLower Key F15 A A Menu Workplace Nop How can I get 3D hardware acceleration for OpenGL? The availability of 3D acceleration depends on the version of XFree86 you are using and the type of video chip you have. If you have an NVIDIA chip, check out the FreeBSD NVIDIA Driver Initiative page, which discusses 3D acceleration for NVIDIA chips using XFree86-4. For other cards with XFree86-4, including the Matrox G200/G400, ATI Rage 128/Radeon, and 3dfx Voodoo 3, 4, 5, and Banshee, information on hardware acceleration is available on the XFree86-4 Direct Rendering on FreeBSD page. Users of XFree86 version 3.3 can use the Utah-GLX port found in graphics/utah-glx to get limited accelerated OpenGL on the Matrox Gx00, ATI Rage Pro, SiS 6326, i810, Savage, and older NVIDIA chips. Networking Where can I get information on diskless booting? Diskless booting means that the FreeBSD box is booted over a network, and reads the necessary files from a server instead of its hard disk. For full details, please read the Handbook entry on diskless booting Can a FreeBSD box be used as a dedicated network router? Yes. Please see the Handbook entry on advanced networking, specifically the section on routing and gateways. Can I connect my Win95 box to the Internet via FreeBSD? Typically, people who ask this question have two PC's at home, one with FreeBSD and one with Win95; the idea is to use the FreeBSD box to connect to the Internet and then be able to access the Internet from the Windows95 box through the FreeBSD box. This is really just a special case of the previous question. ... and the answer is yes! In FreeBSD 3.x, user-mode &man.ppp.8; contains a option. If you run &man.ppp.8; with the , set gateway_enable to YES in /etc/rc.conf, and configure your Windows machine correctly, this should work fine. More detailed information about setting this up can be found in the Pedantic PPP Primer by Steve Sims. If you are using kernel-mode PPP, or have an Ethernet connection to the Internet, you will have to use &man.natd.8;. Please look at the natd section of this FAQ. Does FreeBSD support SLIP and PPP? Yes. See the manual pages for &man.slattach.8;, &man.sliplogin.8;, &man.ppp.8;, and &man.pppd.8;. &man.ppp.8; and &man.pppd.8; provide support for both incoming and outgoing connections, while &man.sliplogin.8; deals exclusively with incoming connections, and &man.slattach.8; deals exclusively with outgoing connections. For more information on how to use these, please see the Handbook chapter on PPP and SLIP. If you only have access to the Internet through a shell account, you may want to have a look at the net/slirp package. It can provide you with (limited) access to services such as ftp and http direct from your local machine. Does FreeBSD support NAT or Masquerading? If you have a local subnet (one or more local machines), but have been allocated only a single IP number from your Internet provider (or even if you receive a dynamic IP number), you may want to look at the &man.natd.8; program. &man.natd.8; allows you to connect an entire subnet to the Internet using only a single IP number. The &man.ppp.8; program has similar functionality built in via the switch. The alias library (&man.libalias.3;) is used in both cases. How do I connect two FreeBSD systems over a parallel line using PLIP? Please see the PLIP section of the Handbook. Why can I not create a /dev/ed0 device? Because they aren't necessary. In the Berkeley networking framework, network interfaces are only directly accessible by kernel code. Please see the /etc/rc.network file and the manual pages for the various network programs mentioned there for more information. If this leaves you totally confused, then you should pick up a book describing network administration on another BSD-related operating system; with few significant exceptions, administering networking on FreeBSD is basically the same as on SunOS 4.0 or Ultrix. How can I set up Ethernet aliases? If the alias is on the same subnet as an address already configured on the interface, then add netmask 0xffffffff to your &man.ifconfig.8; command-line, as in the following: &prompt.root; ifconfig ed0 alias 192.0.2.2 netmask 0xffffffff Otherwise, just specify the network address and netmask as usual: &prompt.root; ifconfig ed0 alias 172.16.141.5 netmask 0xffffff00 How do I get my 3C503 to use the other network port? If you want to use the other ports, you will have to specify an additional parameter on the &man.ifconfig.8; command line. The default port is link0. To use the AUI port instead of the BNC one, use link2. These flags should be specified using the ifconfig_* variables in /etc/rc.conf (see &man.rc.conf.5;). Why am I having trouble with NFS and FreeBSD? Certain PC network cards are better than others (to put it mildly) and can sometimes cause problems with network intensive applications like NFS. See the Handbook entry on NFS for more information on this topic. Why can I not NFS-mount from a Linux box? Some versions of the Linux NFS code only accept mount requests from a privileged port; try &prompt.root; mount -o -P linuxbox:/blah /mnt Why can I not NFS-mount from a Sun box? Sun workstations running SunOS 4.X only accept mount requests from a privileged port; try &prompt.root; mount -o -P sunbox:/blah /mnt Why does mountd keep telling me it can't change attributes and that I have a bad exports list on my FreeBSD NFS server? The most frequent problem is not understanding the correct format of /etc/exports. Please review &man.exports.5; and the NFS entry in the Handbook, especially the section on configuring NFS. Why am I having problems talking PPP to NeXTStep machines? Try disabling the TCP extensions in /etc/rc.conf (see &man.rc.conf.5;) by changing the following variable to NO: tcp_extensions=NO Xylogic's Annex boxes are also broken in this regard and you must use the above change to connect thru them. How do I enable IP multicast support? Multicast host operations are fully supported in FreeBSD 2.0 and later by default. If you want your box to run as a multicast router, you will need to recompile your kernel with the MROUTING option and run &man.mrouted.8;. FreeBSD 2.2 and later will start &man.mrouted.8; at boot time if the flag mrouted_enable is set to "YES" in /etc/rc.conf. MBONE tools are available in their own ports category, mbone. If you are looking for the conference tools vic and vat, look there! Which network cards are based on the DEC PCI chipset? Here is a list compiled by Glen Foster gfoster@driver.nsta.org, with some more modern additions: Network cards based on the DEC PCI chipset Vendor Model ASUS PCI-L101-TB Accton ENI1203 Cogent EM960PCI Compex ENET32-PCI D-Link DE-530 Dayna DP1203, DP2100 DEC DE435, DE450 Danpex EN-9400P3 JCIS Condor JC1260 Linksys EtherPCI Mylex LNP101 SMC EtherPower 10/100 (Model 9332) SMC EtherPower (Model 8432) TopWare TE-3500P Znyx (2.2.x) ZX312, ZX314, ZX342, ZX345, ZX346, ZX348 Znyx (3.x) ZX345Q, ZX346Q, ZX348Q, ZX412Q, ZX414, ZX442, ZX444, ZX474, ZX478, ZX212, ZX214 (10mbps/hd)
Why do I have to use the FQDN for hosts on my site? You will probably find that the host is actually in a different domain; for example, if you are in foo.example.org and you wish to reach a host called mumble in the example.org domain, you will have to refer to it by the fully-qualified domain name, mumble.example.org, instead of just mumble. Traditionally, this was allowed by BSD BIND resolvers. However the current version of bind (see &man.named.8;) that ships with FreeBSD no longer provides default abbreviations for non-fully qualified domain names other than the domain you are in. So an unqualified host mumble must either be found as mumble.foo.example.org, or it will be searched for in the root domain. This is different from the previous behavior, where the search continued across mumble.example.org, and mumble.edu. Have a look at RFC 1535 for why this was considered bad practice, or even a security hole. As a good workaround, you can place the line search foo.example.org example.org instead of the previous domain foo.example.org into your /etc/resolv.conf file (see &man.resolv.conf.5;). However, make sure that the search order does not go beyond the boundary between local and public administration, as RFC 1535 calls it. Why do I get an error, Permission denied, for all networking operations? If you have compiled your kernel with the IPFIREWALL option, you need to be aware that the default policy as of 2.1.7R (this actually changed during 2.1-STABLE development) is to deny all packets that are not explicitly allowed. If you had unintentionally misconfigured your system for firewalling, you can restore network operability by typing the following while logged in as root: &prompt.root; ipfw add 65534 allow all from any to any You can also set firewall_type="open" in /etc/rc.conf. For further information on configuring a FreeBSD firewall, see the Handbook section. How much overhead does IPFW incur? Please see the Handbook's Firewalls section, specifically the section on IPFW Overhead & Optimization. Why is my ipfw fwd rule to redirect a service to another machine not working? Possibly because you want to do network address translation (NAT) and not just forward packets. A fwd rule does exactly what it says; it forwards packets. It does not actually change the data inside the packet. Say we have a rule like: 01000 fwd 10.0.0.1 from any to foo 21 When a packet with a destination address of foo arrives at the machine with this rule, the packet is forwarded to 10.0.0.1, but it still has the destination address of foo! The destination address of the packet is not changed to 10.0.0.1. Most machines would probably drop a packet that they receive with a destination address that is not their own. Therefore, using a fwd rule does not often work the way the user expects. This behavior is a feature and not a bug. See the FAQ about redirecting services, the &man.natd.8; manual, or one of the several port redirecting utilities in the ports collection for a correct way to do this. How can I redirect service requests from one machine to another? You can redirect FTP (and other service) request with the socket package, available in the ports tree in category sysutils. Simply replace the service's command line to call socket instead, like so: ftp stream tcp nowait nobody /usr/local/bin/socket socket ftp.example.com ftp where ftp.example.com and ftp are the host and port to redirect to, respectively. Where can I get a bandwidth management tool? There are three bandwidth management tools available for FreeBSD. &man.dummynet.4; is integrated into FreeBSD (or more specifically, &man.ipfw.4;); ALTQ is available for free; Bandwidth Manager from Emerging Technologies is a commercial product. Why do I get /dev/bpf0: device not configured? You are running a program that requires the Berkeley Packet Filter (&man.bpf.4;), but it's not in your kernel. Add this to your kernel config file and build a new kernel: pseudo-device bpf # Berkeley Packet Filter After rebooting, create the device node. This can be accomplished by going to the /dev directory and running: &prompt.root; sh MAKEDEV bpf0 Please see the Handbook entry on device nodes for more information on creating devices. How do I mount a disk from a Windows machine that is on my network, like smbmount in Linux? Use the SMBFS toolset. It includes a set of kernel modifications and a set of userland programs. The programs and information are available as net/smbfs in the ports collection, or in the base system as of 4.5-RELEASE and later. What are these messages about icmp-response bandwidth limit 300/200 pps in my log files? This is the kernel telling you that some activity is provoking it to send more ICMP or TCP reset (RST) responses than it thinks it should. ICMP responses are often generated as a result of attempted connections to unused UDP ports. TCP resets are generated as a result of attempted connections to unopened TCP ports. Among others, these are the kinds of activities which may cause these messages: Brute-force denial of service (DoS) attacks (as opposed to single-packet attacks which exploit a specific vulnerability). Port scans which attempt to connect to a large number of ports (as opposed to only trying a few well-known ports). The first number in the message tells you how many packets the kernel would have sent if the limit was not in place, and the second number tells you the limit. You can control the limit using the net.inet.icmp.icmplim sysctl variable like this, where 300 is the limit in packets per second: &prompt.root; sysctl -w net.inet.icmp.icmplim=300 If you do not want to see messages about this in your log files, but you still want the kernel to do response limiting, you can use the net.inet.icmp.icmplim_output sysctl variable to disable the output like this: &prompt.root; sysctl -w net.inet.icmp.icmplim_output=0 Finally, if you want to disable response limiting, you can set the net.inet.icmp.icmplim sysctl variable (see above for an example) to 0. Disabling response limiting is discouraged for the reasons listed above. What are these arp: unknown hardware address format error messages? This means that some device on your local Ethernet is using a MAC address in a format that FreeBSD does not recognize. This is probably caused by someone experimenting with an Ethernet card somewhere else on the network. You will see this most commonly on cable modem networks. It is harmless, and should not affect the performance of your FreeBSD machine. I've just installed CVSup but trying to execute it produces errors. What is wrong? First, see if the error message you are receiving is like the one shown below. /usr/libexec/ld-elf.so.1: Shared object "libXaw.so.6" not found Errors like these are caused by installing the net/cvsup port on a machine which does not have the XFree86 suite. If you want to use the GUI included with CVSup you will need to install XFree86 now. Alternatively if you just wish to use CVSup from a command line you should delete the package previously installed. Then install the net/cvsup-without-gui port. This is covered in more detail in the CVSup section of the Handbook. Security BIND (named) is listening on port 53 and some other high-numbered port. What is going on? FreeBSD 3.0 and later use a version of BIND that uses a random high-numbered port for outgoing queries. If you want to use port 53 for outgoing queries, either to get past a firewall or to make yourself feel better, you can try the following in /etc/namedb/named.conf: options { query-source address * port 53; }; You can replace the * with a single IP address if you want to tighten things further. Congratulations, by the way. It is good practice to read your &man.sockstat.1; output and notice odd things! Sendmail is listening on port 587 as well as the standard port 25! What is going on? Recent versions of Sendmail support a mail submission feature that runs over port 587. This is not yet widely supported, but is growing in popularity. What is this UID 0 toor account? Have I been compromised? Do not worry. toor is an alternative superuser account (toor is root spelt backwards). Previously it was created when the &man.bash.1; shell was installed but now it is created by default. It is intended to be used with a non-standard shell so you do not have to change root's default shell. This is important as shells which are not part of the base distribution (for example a shell installed from ports or packages) are likely be to be installed in /usr/local/bin which, by default, resides on a different filesystem. If root's shell is located in /usr/local/bin and /usr (or whatever filesystem contains /usr/local/bin) is not mounted for some reason, root will not be able to log in to fix a problem (although if you reboot into single user mode you will be prompted for the path to a shell). Some people use toor for day-to-day root tasks with a non-standard shell, leaving root, with a standard shell, for single user mode or emergencies. By default you cannot log in using toor as it does not have a password, so log in as root and set a password for toor if you want to use it. Why is suidperl not working properly? For security reasons, suidperl is installed without the suid bit by default. The system administrator can enable suid behavior with the following command. &prompt.root; chmod u+s /usr/bin/suidperl If you want suidperl to be built suid during upgrades from source, edit /etc/make.conf and add ENABLE_SUIDPERL=true before you run make buildworld. PPP I cannot make &man.ppp.8; work. What am I doing wrong? You should first read the &man.ppp.8; man page and the PPP section of the handbook. Enable logging with the command set log Phase Chat Connect Carrier lcp ipcp ccp command This command may be typed at the &man.ppp.8; command prompt or it may be entered in the /etc/ppp/ppp.conf configuration file (the start of the default section is the best place to put it). Make sure that /etc/syslog.conf (see &man.syslog.conf.5;) contains the lines !ppp *.* /var/log/ppp.log and that the file /var/log/ppp.log exists. You can now find out a lot about what is going on from the log file. Do not worry if it does not all make sense. If you need to get help from someone, it may make sense to them. If your version of &man.ppp.8; does not understand the set log command, you should download the latest version. It will build on FreeBSD version 2.1.5 and higher. Why does &man.ppp.8; hang when I run it? This is usually because your hostname will not resolve. The best way to fix this is to make sure that /etc/hosts is consulted by your resolver first by editing /etc/host.conf and putting the hosts line first. Then, simply put an entry in /etc/hosts for your local machine. If you have no local network, change your localhost line: 127.0.0.1 foo.bar.com foo localhost Otherwise, simply add another entry for your host. Consult the relevant man pages for more details. You should be able to successfully ping -c1 `hostname` when you are done. Why will &man.ppp.8; not dial in -auto mode? First, check that you have got a default route. By running netstat -rn (see &man.netstat.1;), you should see two entries like this: Destination Gateway Flags Refs Use Netif Expire default 10.0.0.2 UGSc 0 0 tun0 10.0.0.2 10.0.0.1 UH 0 0 tun0 This is assuming that you have used the addresses from the handbook, the man page or from the ppp.conf.sample file. If you do not have a default route, it may be because you are running an old version of &man.ppp.8; that does not understand the word HISADDR in the ppp.conf file. If your version of &man.ppp.8; is from before FreeBSD 2.2.5, change the add 0 0 HISADDR line to one saying add 0 0 10.0.0.2 Another reason for the default route line being missing is that you have mistakenly set up a default router in your /etc/rc.conf (see &man.rc.conf.5;) file (this file was called /etc/sysconfig prior to release 2.2.2), and you have omitted the line saying delete ALL from ppp.conf. If this is the case, go back to the Final system configuration section of the handbook. What does No route to host mean? This error is usually due to a missing MYADDR: delete ALL add 0 0 HISADDR section in your /etc/ppp/ppp.linkup file. This is only necessary if you have a dynamic IP address or do not know the address of your gateway. If you are using interactive mode, you can type the following after entering packet mode (packet mode is indicated by the capitalized PPP in the prompt): delete ALL add 0 0 HISADDR Refer to the PPP and Dynamic IP addresses section of the handbook for further details. Why does my connection drop after about 3 minutes? The default PPP timeout is 3 minutes. This can be adjusted with the line set timeout NNN where NNN is the number of seconds of inactivity before the connection is closed. If NNN is zero, the connection is never closed due to a timeout. It is possible to put this command in the ppp.conf file, or to type it at the prompt in interactive mode. It is also possible to adjust it on the fly while the line is active by connecting to ppps server socket using &man.telnet.1; or &man.pppctl.8;. Refer to the &man.ppp.8; man page for further details. Why does my connection drop under heavy load? If you have Link Quality Reporting (LQR) configured, it is possible that too many LQR packets are lost between your machine and the peer. Ppp deduces that the line must therefore be bad, and disconnects. Prior to FreeBSD version 2.2.5, LQR was enabled by default. It is now disabled by default. LQR can be disabled with the line disable lqr Why does my connection drop after a random amount of time? Sometimes, on a noisy phone line or even on a line with call waiting enabled, your modem may hang up because it thinks (incorrectly) that it lost carrier. There is a setting on most modems for determining how tolerant it should be to temporary losses of carrier. On a USR Sportster for example, this is measured by the S10 register in tenths of a second. To make your modem more forgiving, you could add the following send-expect sequence to your dial string: set dial "...... ATS10=10 OK ......" Refer to your modem manual for details. Why does my connection hang after a random amount of time? Many people experience hung connections with no apparent explanation. The first thing to establish is which side of the link is hung. If you are using an external modem, you can simply try using &man.ping.8; to see if the TD light is flashing when you transmit data. If it flashes (and the RD light does not), the problem is with the remote end. If TD does not flash, the problem is local. With an internal modem, you will need to use the set server command in your ppp.conf file. When the hang occurs, connect to &man.ppp.8; using &man.pppctl.8;. If your network connection suddenly revives (PPP was revived due to the activity on the diagnostic socket) or if you cannot connect (assuming the set socket command succeeded at startup time), the problem is local. If you can connect and things are still hung, enable local async logging with set log local async and use &man.ping.8; from another window or terminal to make use of the link. The async logging will show you the data being transmitted and received on the link. If data is going out and not coming back, the problem is remote. Having established whether the problem is local or remote, you now have two possibilities: The remote end is not responding. What can I do? There is very little you can do about this. Most ISPs will refuse to help if you are not running a Microsoft OS. You can enable lqr in your ppp.conf file, allowing &man.ppp.8; to detect the remote failure and hang up, but this detection is relatively slow and therefore not that useful. You may want to avoid telling your ISP that you are running user-PPP... First, try disabling all local compression by adding the following to your configuration: disable pred1 deflate deflate24 protocomp acfcomp shortseq vj deny pred1 deflate deflate24 protocomp acfcomp shortseq vj Then reconnect to ensure that this makes no difference. If things improve or if the problem is solved completely, determine which setting makes the difference through trial and error. This will provide good ammunition when you contact your ISP (although it may make it apparent that you are not running a Microsoft product). Before contacting your ISP, enable async logging locally and wait until the connection hangs again. This may use up quite a bit of disk space. The last data read from the port may be of interest. It is usually ascii data, and may even describe the problem (Memory fault, core dumped?). If your ISP is helpful, they should be able to enable logging on their end, then when the next link drop occurs, they may be able to tell you why their side is having a problem. Feel free to send the details to &a.brian;, or even to ask your ISP to contact me directly. &man.ppp.8; has hung. What can I do? Your best bet here is to rebuild &man.ppp.8; by adding CFLAGS+=-g and STRIP= to the end of the Makefile, then doing a make clean && make && make install. When &man.ppp.8; hangs, find the &man.ppp.8; process id with ps ajxww | fgrep ppp and run gdb ppp PID. From the gdb prompt, you can then use bt to get a stack trace. Send the results to brian@Awfulhak.org. Why does nothing happen after the Login OK! message? Prior to FreeBSD version 2.2.5, once the link was established, &man.ppp.8; would wait for the peer to initiate the Line Control Protocol (LCP). Many ISPs will not initiate negotiations and expect the client to do so. To force &man.ppp.8; to initiate the LCP, use the following line: set openmode active It usually does no harm if both sides initiate negotiation, so openmode is now active by default. However, the next section explains when it does do some harm. I keep seeing errors about magic being the same. What does it mean? Occasionally, just after connecting, you may see messages in the log that say magic is the same. Sometimes, these messages are harmless, and sometimes one side or the other exits. Most PPP implementations cannot survive this problem, and even if the link seems to come up, you will see repeated configure requests and configure acknowledgments in the log file until &man.ppp.8; eventually gives up and closes the connection. This normally happens on server machines with slow disks that are spawning a getty on the port, and executing &man.ppp.8; from a login script or program after login. I have also heard reports of it happening consistently when using slirp. The reason is that in the time taken between &man.getty.8; exiting and &man.ppp.8; starting, the client-side &man.ppp.8; starts sending Line Control Protocol (LCP) packets. Because ECHO is still switched on for the port on the server, the client &man.ppp.8; sees these packets reflect back. One part of the LCP negotiation is to establish a magic number for each side of the link so that reflections can be detected. The protocol says that when the peer tries to negotiate the same magic number, a NAK should be sent and a new magic number should be chosen. During the period that the server port has ECHO turned on, the client &man.ppp.8; sends LCP packets, sees the same magic in the reflected packet and NAKs it. It also sees the NAK reflect (which also means &man.ppp.8; must change its magic). This produces a potentially enormous number of magic number changes, all of which are happily piling into the server's tty buffer. As soon as &man.ppp.8; starts on the server, it is flooded with magic number changes and almost immediately decides it has tried enough to negotiate LCP and gives up. Meanwhile, the client, who no longer sees the reflections, becomes happy just in time to see a hangup from the server. This can be avoided by allowing the peer to start negotiating with the following line in your ppp.conf file: set openmode passive This tells &man.ppp.8; to wait for the server to initiate LCP negotiations. Some servers however may never initiate negotiations. If this is the case, you can do something like: set openmode active 3 This tells &man.ppp.8; to be passive for 3 seconds, and then to start sending LCP requests. If the peer starts sending requests during this period, &man.ppp.8; will immediately respond rather than waiting for the full 3 second period. LCP negotiations continue until the connection is closed. What is wrong? There is currently an implementation mis-feature in &man.ppp.8; where it does not associate LCP, CCP & IPCP responses with their original requests. As a result, if one PPP implementation is more than 6 seconds slower than the other side, the other side will send two additional LCP configuration requests. This is fatal. Consider two implementations, A and B. A starts sending LCP requests immediately after connecting and B takes 7 seconds to start. When B starts, A has sent 3 LCP REQs. We are assuming the line has ECHO switched off, otherwise we would see magic number problems as described in the previous section. B sends a REQ, then an ACK to the first of A's REQs. This results in A entering the OPENED state and sending and ACK (the first) back to B. In the meantime, B sends back two more ACKs in response to the two additional REQs sent by A before B started up. B then receives the first ACK from A and enters the OPENED state. A receives the second ACK from B and goes back to the REQ-SENT state, sending another (forth) REQ as per the RFC. It then receives the third ACK and enters the OPENED state. In the meantime, B receives the forth REQ from A, resulting in it reverting to the ACK-SENT state and sending another (second) REQ and (forth) ACK as per the RFC. A gets the REQ, goes into REQ-SENT and sends another REQ. It immediately receives the following ACK and enters OPENED. This goes on until one side figures out that they are getting nowhere and gives up. The best way to avoid this is to configure one side to be passive - that is, make one side wait for the other to start negotiating. This can be done with the set openmode passive command. Care should be taken with this option. You should also use the set stopped N command to limit the amount of time that &man.ppp.8; waits for the peer to begin negotiations. Alternatively, the set openmode active N command (where N is the number of seconds to wait before starting negotiations) can be used. Check the manual page for details. Why does &man.ppp.8; lock up shortly after connection? Prior to version 2.2.5 of FreeBSD, it was possible that your link was disabled shortly after connection due to &man.ppp.8; mis-handling Predictor1 compression negotiation. This would only happen if both sides tried to negotiate different Compression Control Protocols (CCP). This problem is now corrected, but if you are still running an old version of &man.ppp.8; the problem can be circumvented with the line disable pred1 Why does &man.ppp.8; lock up when I shell out to test it? When you execute the shell or ! command, &man.ppp.8; executes a shell (or if you have passed any arguments, &man.ppp.8; will execute those arguments). Ppp will wait for the command to complete before continuing. If you attempt to use the PPP link while running the command, the link will appear to have frozen. This is because &man.ppp.8; is waiting for the command to complete. If you wish to execute commands like this, use the !bg command instead. This will execute the given command in the background, and &man.ppp.8; can continue to service the link. Why does &man.ppp.8; over a null-modem cable never exit? There is no way for &man.ppp.8; to automatically determine that a direct connection has been dropped. This is due to the lines that are used in a null-modem serial cable. When using this sort of connection, LQR should always be enabled with the line enable lqr LQR is accepted by default if negotiated by the peer. Why does &man.ppp.8; dial for no reason in -auto mode? If &man.ppp.8; is dialing unexpectedly, you must determine the cause, and set up Dial filters (dfilters) to prevent such dialing. To determine the cause, use the following line: set log +tcp/ip This will log all traffic through the connection. The next time the line comes up unexpectedly, you will see the reason logged with a convenient timestamp next to it. You can now disable dialing under these circumstances. Usually, this sort of problem arises due to DNS lookups. To prevent DNS lookups from establishing a connection (this will not prevent &man.ppp.8; from passing the packets through an established connection), use the following: set dfilter 1 deny udp src eq 53 set dfilter 2 deny udp dst eq 53 set dfilter 3 permit 0/0 0/0 This is not always suitable, as it will effectively break your demand-dial capabilities - most programs will need a DNS lookup before doing any other network related things. In the DNS case, you should try to determine what is actually trying to resolve a host name. A lot of the time, &man.sendmail.8; is the culprit. You should make sure that you tell sendmail not to do any DNS lookups in its configuration file. See the section on Mail Configuration for details on how to create your own configuration file and what should go into it. You may also want to add the following line to your .mc file: define(`confDELIVERY_MODE', `d')dnl This will make sendmail queue everything until the queue is run (usually, sendmail is invoked with , telling it to run the queue every 30 minutes) or until a sendmail -q is done (perhaps from your ppp.linkup file). What do these CCP errors mean? I keep seeing the following errors in my log file: CCP: CcpSendConfigReq CCP: Received Terminate Ack (1) state = Req-Sent (6) This is because &man.ppp.8; is trying to negotiate Predictor1 compression, and the peer does not want to negotiate any compression at all. The messages are harmless, but if you wish to remove them, you can disable Predictor1 compression locally too: disable pred1 Why does &man.ppp.8; lock up during file transfers with IO errors? Under FreeBSD 2.2.2 and before, there was a bug in the tun driver that prevents incoming packets of a size larger than the tun interface's MTU size. Receipt of a packet greater than the MTU size results in an IO error being logged via syslogd. The PPP specification says that an MRU of 1500 should always be accepted as a minimum, despite any LCP negotiations, therefore it is possible that should you decrease the MTU to less than 1500, your ISP will transmit packets of 1500 regardless, and you will tickle this non-feature - locking up your link. The problem can be circumvented by never setting an MTU of less than 1500 under FreeBSD 2.2.2 or before. Why does &man.ppp.8; not log my connection speed? In order to log all lines of your modem conversation, you must enable the following: set log +connect This will make &man.ppp.8; log everything up until the last requested expect string. If you wish to see your connect speed and are using PAP or CHAP (and therefore do not have anything to chat after the CONNECT in the dial script - no set login script), you must make sure that you instruct &man.ppp.8; to expect the whole CONNECT line, something like this: set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 4 \ \"\" ATZ OK-ATZ-OK ATDT\\T TIMEOUT 60 CONNECT \\c \\n" Here, we get our CONNECT, send nothing, then expect a line-feed, forcing &man.ppp.8; to read the whole CONNECT response. Why does &man.ppp.8; ignore the \ character in my chat script? Ppp parses each line in your config files so that it can interpret strings such as set phone "123 456 789" correctly (and realize that the number is actually only one argument. In order to specify a " character, you must escape it using a backslash (\). When the chat interpreter parses each argument, it re-interprets the argument in order to find any special escape sequences such as \P or \T (see the man page). As a result of this double-parsing, you must remember to use the correct number of escapes. If you wish to actually send a \ character to (say) your modem, you would need something like: set dial "\"\" ATZ OK-ATZ-OK AT\\\\X OK" resulting in the following sequence: ATZ OK AT\X OK or set phone 1234567 set dial "\"\" ATZ OK ATDT\\T" resulting in the following sequence: ATZ OK ATDT1234567 Why does &man.ppp.8; get a seg-fault, but I see no ppp.core file? Ppp (or any other program for that matter) should never dump core. Because &man.ppp.8; runs with an effective user id of 0, the operating system will not write &man.ppp.8;'s core image to disk before terminating it. If, however &man.ppp.8; is actually terminating due to a segmentation violation or some other signal that normally causes core to be dumped, and you are sure you are using the latest version (see the start of this section), then you should do the following: &prompt.user; tar xfz ppp-*.src.tar.gz &prompt.user; cd ppp*/ppp &prompt.user; echo STRIP= >>Makefile &prompt.user; echo CFLAGS+=-g >>Makefile &prompt.user; make clean all &prompt.user; su &prompt.root; make install &prompt.root; chmod 555 /usr/sbin/ppp You will now have a debuggable version of &man.ppp.8; installed. You will have to be root to run &man.ppp.8; as all of its privileges have been revoked. When you start &man.ppp.8;, take a careful note of what your current directory was at the time. Now, if and when &man.ppp.8; receives the segmentation violation, it will dump a core file called ppp.core. You should then do the following: &prompt.user; su &prompt.root; gdb /usr/sbin/ppp ppp.core (gdb) bt ..... (gdb) f 0 .... (gdb) i args .... (gdb) l ..... All of this information should be given alongside your question, making it possible to diagnose the problem. If you are familiar with gdb, you may wish to find out some other bits and pieces such as what actually caused the dump and the addresses & values of the relevant variables. Why does the process that forces a dial in auto mode never connect? This was a known problem with &man.ppp.8; set up to negotiate a dynamic local IP number with the peer in auto mode. It is fixed in the latest version - search the man page for iface. The problem was that when that initial program calls &man.connect.2;, the IP number of the tun interface is assigned to the socket endpoint. The kernel creates the first outgoing packet and writes it to the tun device. &man.ppp.8; then reads the packet and establishes a connection. If, as a result of &man.ppp.8;'s dynamic IP assignment, the interface address is changed, the original socket endpoint will be invalid. Any subsequent packets sent to the peer will usually be dropped. Even if they are not, any responses will not route back to the originating machine as the IP number is no longer owned by that machine. There are several theoretical ways to approach this problem. It would be nicest if the peer would re-assign the same IP number if possible :-) The current version of &man.ppp.8; does this, but most other implementations do not. The easiest method from our side would be to never change the tun interface IP number, but instead to change all outgoing packets so that the source IP number is changed from the interface IP to the negotiated IP on the fly. This is essentially what the iface-alias option in the latest version of &man.ppp.8; is doing (with the help of &man.libalias.3; and &man.ppp.8;'s switch) - it is maintaining all previous interface addresses and NATing them to the last negotiated address. Another alternative (and probably the most reliable) would be to implement a system call that changes all bound sockets from one IP to another. &man.ppp.8; would use this call to modify the sockets of all existing programs when a new IP number is negotiated. The same system call could be used by dhcp clients when they are forced to re-bind() their sockets. Yet another possibility is to allow an interface to be brought up without an IP number. Outgoing packets would be given an IP number of 255.255.255.255 up until the first SIOCAIFADDR ioctl is done. This would result in fully binding the socket. It would be up to &man.ppp.8; to change the source IP number, but only if it is set to 255.255.255.255, and only the IP number and IP checksum would need to change. This, however is a bit of a hack as the kernel would be sending bad packets to an improperly configured interface, on the assumption that some other mechanism is capable of fixing things retrospectively. Why do most games not work with the -nat switch? The reason games and the like do not work when libalias is in use is that the machine on the outside will try to open a connection or send (unsolicited) UDP packets to the machine on the inside. The NAT software does not know that it should send these packets to the interior machine. To make things work, make sure that the only thing running is the software that you are having problems with, then either run tcpdump on the tun interface of the gateway or enable &man.ppp.8; tcp/ip logging (set log +tcp/ip) on the gateway. When you start the offending software, you should see packets passing through the gateway machine. When something comes back from the outside, it will be dropped (that is the problem). Note the port number of these packets then shut down the offending software. Do this a few times to see if the port numbers are consistent. If they are, then the following line in the relevant section of /etc/ppp/ppp.conf will make the software functional: nat port proto internalmachine:port port where proto is either tcp or udp, internalmachine is the machine that you want the packets to be sent to and port is the destination port number of the packets. You will not be able to use the software on other machines without changing the above command, and running the software on two internal machines at the same time is out of the question - after all, the outside world is seeing your entire internal network as being just a single machine. If the port numbers are not consistent, there are three more options: Submit support in libalias. Examples of special cases can be found in /usr/src/lib/libalias/alias_*.c (alias_ftp.c is a good prototype). This usually involves reading certain recognised outgoing packets, identifying the instruction that tells the outside machine to initiate a connection back to the internal machine on a specific (random) port and setting up a route in the alias table so that the subsequent packets know where to go. This is the most difficult solution, but it is the best and will make the software work with multiple machines. Use a proxy. The application may support socks5 for example, or (as in the cvsup case) may have a passive option that avoids ever requesting that the peer open connections back to the local machine. Redirect everything to the internal machine using nat addr. This is the sledge-hammer approach. Has anybody made a list of useful port numbers? Not yet, but this is intended to grow into such a list (if any interest is shown). In each example, internal should be replaced with the IP number of the machine playing the game. Asheron's Call nat port udp internal :65000 65000 Manually change the port number within the game to 65000. If you have got a number of machines that you wish to play on assign a unique port number for each (i.e. 65001, 65002, etc) and add a nat port line for each one. Half Life nat port udp internal:27005 27015 PCAnywhere 8.0 nat port udp internal:5632 5632 nat port tcp internal:5631 5631 Quake nat port udp internal:6112 6112 Alternatively, you may want to take a look at www.battle.net for Quake proxy support. Quake 2 nat port udp internal:27901 27910 nat port udp internal:60021 60021 nat port udp internal:60040 60040 Red Alert nat port udp internal:8675 8675 nat port udp internal:5009 5009 What are FCS errors? FCS stands for Frame Check Sequence. Each PPP packet has a checksum attached to ensure that the data being received is the data being sent. If the FCS of an incoming packet is incorrect, the packet is dropped and the HDLC FCS count is increased. The HDLC error values can be displayed using the show hdlc command. If your link is bad (or if your serial driver is dropping packets), you will see the occasional FCS error. This is not usually worth worrying about although it does slow down the compression protocols substantially. If you have an external modem, make sure your cable is properly shielded from interference - this may eradicate the problem. If your link freezes as soon as you have connected and you see a large number of FCS errors, this may be because your link is not 8 bit clean. Make sure your modem is not using software flow control (XON/XOFF). If your datalink must use software flow control, use the command set accmap 0x000a0000 to tell &man.ppp.8; to escape the ^Q and ^S characters. Another reason for seeing too many FCS errors may be that the remote end has stopped talking PPP. You may want to enable async logging at this point to determine if the incoming data is actually a login or shell prompt. If you have a shell prompt at the remote end, it is possible to terminate &man.ppp.8; without dropping the line by using the close lcp command (a following term command will reconnect you to the shell on the remote machine. If nothing in your log file indicates why the link might have been terminated, you should ask the remote administrator (your ISP?) why the session was terminated. Why do MacOS and Windows 98 connections freeze when running PPPoE on the gateway? Thanks to Michael Wozniak mwozniak@netcom.ca for figuring this out and Dan Flemming danflemming@mac.com for the Mac solution: This is due to what is called a Black Hole router. MacOS and Windows 98 (and maybe other Microsoft OSs) send TCP packets with a requested segment size too big to fit into a PPPoE frame (MTU is 1500 by default for Ethernet) and have the do not fragment bit set (default of TCP) and the Telco router is not sending ICMP must fragment back to the www site you are trying to load. (Alternatively, the router is sending the ICMP packet correctly, but the firewall at the www site is dropping it.) When the www server is sending you frames that do not fit into the PPPoE pipe the Telco router drops them on the floor and your page does not load (some pages/graphics do as they are smaller than a MSS.) This seems to be the default of most Telco PPPoE configurations (if only they knew how to program a router... sigh...) One fix is to use regedit on your 95/98 boxes to add the following registry entry... HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\NetTrans\0000\MaxMTU It should be a string with a value 1436, as some ADSL routers are reported to be unable to deal with packets larger than this. This registry key has been changed to Tcpip\Parameters\Interfaces\ID for adapter\MTU in Windows 2000 and becomes a DWORD. Refer to the Microsoft Knowledge Base documents Q158474 - Windows TCPIP Registry Entries and Q120642 - TCPIP & NBT Configuration Parameters for Windows NT for more information on changing Windows MTU to work with a NAT router. Another regedit possibility under Windows 2000 is to set the Tcpip\Parameters\Interfaces\ID for adapter\EnablePMTUBHDetect DWORD to 1 as mentioned in the Microsoft document 120642 mentioned above. Unfortunately, MacOS does not provide an interface for changing TCP/IP settings. However, there is commercial software available, such as OTAdvancedTuner (OT for OpenTransport, the MacOS TCP/IP stack) by Sustainable Softworks, that will allow users to customize TCP/IP settings. MacOS NAT users should select ip_interface_MTU from the drop-down menu, enter 1450 instead of 1500 in the box, click the box next to Save as Auto Configure, and click Make Active. The latest version of &man.ppp.8; (2.3 or greater) has an enable tcpmssfixup command that will automatically adjust the MSS to an appropriate value. This facility is enabled by default. If you are stuck with an older version of &man.ppp.8;, you may want to look at the tcpmssd port. None of this helps - I am desperate! What can I do? If all else fails, send as much information as you can, including your config files, how you are starting &man.ppp.8;, the relevant parts of your log file and the output of the netstat -rn command (before and after connecting) to the &a.questions; or the comp.unix.bsd.freebsd.misc news group, and someone should point you in the right direction. Serial Communications This section answers common questions about serial communications with FreeBSD. PPP and SLIP are covered in the section. How do I tell if FreeBSD found my serial ports? As the FreeBSD kernel boots, it will probe for the serial ports in your system for which the kernel was configured. You can either watch your system closely for the messages it prints or run the command &prompt.user; dmesg | grep sio after your system is up and running. Here is some example output from the above command: sio0 at 0x3f8-0x3ff irq 4 on isa sio0: type 16550A sio1 at 0x2f8-0x2ff irq 3 on isa sio1: type 16550A This shows two serial ports. The first is on irq 4, is using port address 0x3f8, and has a 16550A-type UART chip. The second uses the same kind of chip but is on irq 3 and is at port address 0x2f8. Internal modem cards are treated just like serial ports---except that they always have a modem attached to the port. The GENERIC kernel includes support for two serial ports using the same irq and port address settings in the above example. If these settings are not right for your system, or if you have added modem cards or have more serial ports than your kernel is configured for, just reconfigure your kernel. See section about building a kernel for more details. How do I tell if FreeBSD found my modem cards? Refer to the answer to the previous question. I just upgraded to 2.0.5 and my tty0X are missing! How do I solve this problem? Do not worry, they have been merged with the ttydX devices. You will have to change any old configuration files you have, though. How do I access the serial ports on FreeBSD? The third serial port, sio2 (see &man.sio.4;, known as COM3 in DOS), is on /dev/cuaa2 for dial-out devices, and on /dev/ttyd2 for dial-in devices. What is the difference between these two classes of devices? You use ttydX for dial-ins. When opening /dev/ttydX in blocking mode, a process will wait for the corresponding cuaaX device to become inactive, and then wait for the carrier detect line to go active. When you open the cuaaX device, it makes sure the serial port is not already in use by the ttydX device. If the port is available, it steals it from the ttydX device. Also, the cuaaX device does not care about carrier detect. With this scheme and an auto-answer modem, you can have remote users log in and you can still dial out with the same modem and the system will take care of all the conflicts. How do I enable support for a multiport serial card? Again, the section on kernel configuration provides information about configuring your kernel. For a multiport serial card, place an &man.sio.4; line for each serial port on the card in the kernel configuration file. But place the irq and vector specifiers on only one of the entries. All of the ports on the card should share one irq. For consistency, use the last serial port to specify the irq. Also, specify the COM_MULTIPORT option. The following example is for an AST 4-port serial card on irq 7: options "COM_MULTIPORT" device sio4 at isa? port 0x2a0 tty flags 0x781 device sio5 at isa? port 0x2a8 tty flags 0x781 device sio6 at isa? port 0x2b0 tty flags 0x781 device sio7 at isa? port 0x2b8 tty flags 0x781 irq 7 vector siointr The flags indicate that the master port has minor number 7 (0x700), diagnostics enabled during probe (0x080), and all the ports share an irq (0x001). Can FreeBSD handle multiport serial cards sharing irqs? Not yet. You will have to use a different irq for each card. Can I set the default serial parameters for a port? The ttydX (or cuaaX) device is the regular device you will want to open for your applications. When a process opens the device, it will have a default set of terminal I/O settings. You can see these settings with the command &prompt.root; stty -a -f /dev/ttyd1 When you change the settings to this device, the settings are in effect until the device is closed. When it is reopened, it goes back to the default set. To make changes to the default set, you can open and adjust the settings of the initial state device. For example, to turn on CLOCAL mode, 8 bits, and XON/XOFF flow control by default for ttyd5, do: &prompt.root; stty -f /dev/ttyid5 clocal cs8 ixon ixoff A good place to do this is in /etc/rc.serial. Now, an application will have these settings by default when it opens ttyd5. It can still change these settings to its liking, though. You can also prevent certain settings from being changed by an application by making adjustments to the lock state device. For example, to lock the speed of ttyd5 to 57600 bps, do &prompt.root; stty -f /dev/ttyld5 57600 Now, an application that opens ttyd5 and tries to change the speed of the port will be stuck with 57600 bps. Naturally, you should make the initial state and lock state devices writable only by root. The &man.MAKEDEV.8; script does NOT do this when it creates the device entries. How can I enable dialup logins on my modem? So you want to become an Internet service provider, eh? First, you will need one or more modems that can auto-answer. Your modem will need to assert carrier-detect when it detects a carrier and not assert it all the time. It will need to hang up the phone and reset itself when the data terminal ready (DTR) line goes from on to off. It should probably use RTS/CTS flow control or no local flow control at all. Finally, it must use a constant speed between the computer and itself, but (to be nice to your callers) it should negotiate a speed between itself and the remote modem. For many Hayes command-set--compatible modems, this command will make these settings and store them in nonvolatile memory: AT &C1 &D3 &K3 &Q6 S0=1 &W See the section on sending AT commands below for information on how to make these settings without resorting to an MS-DOS terminal program. Next, make an entry in /etc/ttys (see &man.ttys.5;) for the modem. This file lists all the ports on which the operating system will await logins. Add a line that looks something like this: ttyd1 "/usr/libexec/getty std.57600" dialup on insecure This line indicates that the second serial port (/dev/ttyd1) has a modem connected running at 57600 bps and no parity (std.57600, which comes from the file /etc/gettytab, see &man.gettytab.5;). The terminal type for this port is dialup. The port is on and is insecure---meaning root logins on the port are not allowed. For dialin ports like this one, use the ttydX entry. It is common practice to use dialup as the terminal type. Many users set up in their .profile or .login files a prompt for the actual terminal type if the starting type is dialup. The example shows the port as insecure. To become root on this port, you have to login as a regular user, then &man.su.1; to become root. If you use secure then root can login in directly. After making modifications to /etc/ttys, you need to send a hangup or HUP signal to the &man.init.8; process: &prompt.root; kill -HUP 1 This forces the &man.init.8; process to reread /etc/ttys. The init process will then start getty processes on all on ports. You can find out if logins are available for your port by typing &prompt.user; ps -ax | grep '[t]tyd1' You should see something like: 747 ?? I 0:00.04 /usr/libexec/getty std.57600 ttyd1 How can I connect a dumb terminal to my FreeBSD box? If you are using another computer as a terminal into your FreeBSD system, get a null modem cable to go between the two serial ports. If you are using an actual terminal, see its accompanying instructions. Then, modify /etc/ttys (see &man.ttys.5;), like above. For example, if you are hooking up a WYSE-50 terminal to the fifth serial port, use an entry like this: ttyd4 "/usr/libexec/getty std.38400" wyse50 on secure This example shows that the port on /dev/ttyd4 has a wyse50 terminal connected at 38400 bps with no parity (std.38400 from /etc/gettytab, see &man.gettytab.5;) and root logins are allowed (secure). Why can I not run tip or cu? On your system, the programs &man.tip.1; and &man.cu.1; are probably executable only by uucp and group dialer. You can use the group dialer to control who has access to your modem or remote systems. Just add yourself to group dialer. Alternatively, you can let everyone on your system run &man.tip.1; and &man.cu.1; by typing: &prompt.root; chmod 4511 /usr/bin/cu &prompt.root; chmod 4511 /usr/bin/tip My stock Hayes modem is not supported---what can I do? Actually, the man page for &man.tip.1; is out of date. There is a generic Hayes dialer already built in. Just use at=hayes in your /etc/remote (see &man.remote.5;) file. The Hayes driver is not smart enough to recognize some of the advanced features of newer modems---messages like BUSY, NO DIALTONE, or CONNECT 115200 will just confuse it. You should turn those messages off when you use &man.tip.1; (using ATX0&W). Also, the dial timeout for &man.tip.1; is 60 seconds. Your modem should use something less, or else tip will think there is a communication problem. Try ATS7=45&W. Actually, as shipped &man.tip.1; does not yet support it fully. The solution is to edit the file tipconf.h in the directory /usr/src/usr.bin/tip/tip. Obviously you need the source distribution to do this. Edit the line #define HAYES 0 to #define HAYES 1. Then make and make install. Everything works nicely after that. How am I expected to enter these AT commands? Make what is called a direct entry in your /etc/remote file (see &man.remote.5;). For example, if your modem is hooked up to the first serial port, /dev/cuaa0, then put in the following line: cuaa0:dv=/dev/cuaa0:br#19200:pa=none Use the highest bps rate your modem supports in the br capability. Then, type tip cuaa0 (see &man.tip.1;) and you will be connected to your modem. If there is no /dev/cuaa0 on your system, do this: &prompt.root; cd /dev &prompt.root; sh MAKEDEV cuaa0 Or use cu as root with the following command: &prompt.root; cu -lline -sspeed with line being the serial port (e.g. /dev/cuaa0) and speed being the speed (e.g.57600). When you are done entering the AT commands hit ~. to exit. Why does the <@> sign for the pn capability not work? The <@> sign in the phone number capability tells tip to look in /etc/phones for a phone number. But the <@> sign is also a special character in capability files like /etc/remote. Escape it with a backslash: pn=\@ How can I dial a phone number on the command line? Put what is called a generic entry in your /etc/remote file (see &man.remote.5;). For example: tip115200|Dial any phone number at 115200 bps:\ :dv=/dev/cuaa0:br#115200:at=hayes:pa=none:du: tip57600|Dial any phone number at 57600 bps:\ :dv=/dev/cuaa0:br#57600:at=hayes:pa=none:du: Then you can do something like tip -115200 5551234. If you prefer &man.cu.1; over &man.tip.1;, use a generic cu entry: cu115200|Use cu to dial any number at 115200bps:\ :dv=/dev/cuaa1:br#57600:at=hayes:pa=none:du: and type cu 5551234 -s 115200. Do I have to type in the bps rate every time I do that? Put in an entry for tip1200 or cu1200, but go ahead and use whatever bps rate is appropriate with the br capability. &man.tip.1; thinks a good default is 1200 bps which is why it looks for a tip1200 entry. You do not have to use 1200 bps, though. How can I more easily access a number of hosts through a terminal server? Rather than waiting until you are connected and typing CONNECT host each time, use tip's cm capability. For example, these entries in /etc/remote (see &man.remote.5;): pain|pain.deep13.com|Forrester's machine:\ :cm=CONNECT pain\n:tc=deep13: muffin|muffin.deep13.com|Frank's machine:\ :cm=CONNECT muffin\n:tc=deep13: deep13:Gizmonics Institute terminal server:\ :dv=/dev/cuaa2:br#38400:at=hayes:du:pa=none:pn=5551234: will let you type tip pain or tip muffin to connect to the hosts pain or muffin; and tip deep13 to get to the terminal server. Can tip try more than one line for each site? This is often a problem where a university has several modem lines and several thousand students trying to use them... Make an entry for your university in /etc/remote (see &man.remote.5;) and use <\@> for the pn capability: big-university:\ :pn=\@:tc=dialout dialout:\ :dv=/dev/cuaa3:br#9600:at=courier:du:pa=none: Then, list the phone numbers for the university in /etc/phones (see &man.phones.5;): big-university 5551111 big-university 5551112 big-university 5551113 big-university 5551114 &man.tip.1; will try each one in the listed order, then give up. If you want to keep retrying, run &man.tip.1; in a while loop. Why do I have to hit CTRL+P twice to send CTRL+P once? CTRL+P is the default force character, used to tell &man.tip.1; that the next character is literal data. You can set the force character to any other character with the ~s escape, which means set a variable. Type ~sforce=single-char followed by a newline. single-char is any single character. If you leave out single-char, then the force character is the nul character, which you can get by typing CTRL+2 or CTRL+SPACE. A pretty good value for single-char is SHIFT+CTRL+6, which I have seen only used on some terminal servers. You can have the force character be whatever you want by specifying the following in your $HOME/.tiprc file: force=single-char Why is everything I type suddenly in UPPER CASE? You must have pressed CTRL+A, &man.tip.1; raise character, specially designed for people with broken caps-lock keys. Use ~s as above and set the variable raisechar to something reasonable. In fact, you can set it to the same as the force character, if you never expect to use either of these features. Here is a sample .tiprc file perfect for Emacs users who need to type CTRL+2 and CTRL+A a lot: force=^^ raisechar=^^ The ^^ is SHIFT+CTRL+6. How can I do file transfers with tip? If you are talking to another Unix system, you can send and receive files with ~p (put) and ~t (take). These commands run &man.cat.1; and &man.echo.1; on the remote system to accept and send files. The syntax is: ~p <local-file> [<remote-file>] ~t <remote-file> [<local-file>] There is no error checking, so you probably should use another protocol, like zmodem. How can I run zmodem with tip? First, install one of the zmodem programs from the ports collection (such as one of the two from the comms category, lrzsz or rzsz. To receive files, start the sending program on the remote end. Then, press enter and type ~C rz (or ~C lrz if you installed lrzsz) to begin receiving them locally. To send files, start the receiving program on the remote end. Then, press enter and type ~C sz files (or ~C lsz files) to send them to the remote system. Why does FreeBSD not find my serial ports, even when the settings are correct? Motherboards and cards with Acer UARTs do not probe properly under the FreeBSD sio probe. Obtain a patch from www.lemis.com to fix your problem. Miscellaneous Questions FreeBSD uses far more swap space than Linux. Why? FreeBSD only appears to use more swap than Linux. In actual fact, it does not. The main difference between FreeBSD and Linux in this regard is that FreeBSD will proactively move entirely idle, unused pages of main memory into swap in order to make more main memory available for active use. Linux tends to only move pages to swap as a last resort. The perceived heavier use of swap is balanced by the more efficient use of main memory. Note that while FreeBSD is proactive in this regard, it does not arbitrarily decide to swap pages when the system is truly idle. Thus you will not find your system all paged out when you get up in the morning after leaving it idle overnight. Why does top show very little free memory even when I have very few programs running? The simple answer is that free memory is wasted memory. Any memory that your programs do not actively allocate is used within the FreeBSD kernel as disk cache. The values shown by &man.top.1; labeled as Inact, Cache, and Buf are all cached data at different aging levels. This cached data means the system does not have to access a slow disk again for data it has accessed recently, thus increasing overall performance. In general, a low value shown for Free memory in &man.top.1; is good, provided it is not very low. Why use (what are) a.out and ELF executable formats? To understand why FreeBSD uses the ELF format, you must first know a little about the 3 currently dominant executable formats for Unix: Prior to FreeBSD 3.x, FreeBSD used the a.out format. &man.a.out.5; The oldest and classic Unix object format. It uses a short and compact header with a magic number at the beginning that is often used to characterize the format (see &man.a.out.5; for more details). It contains three loaded segments: .text, .data, and .bss plus a symbol table and a string table. COFF The SVR3 object format. The header now comprises a section table, so you can have more than just .text, .data, and .bss sections. ELF The successor to COFF, featuring Multiple sections and 32-bit or 64-bit possible values. One major drawback: ELF was also designed with the assumption that there would be only one ABI per system architecture. That assumption is actually quite incorrect, and not even in the commercial SYSV world (which has at least three ABIs: SVR4, Solaris, SCO) does it hold true. FreeBSD tries to work around this problem somewhat by providing a utility for branding a known ELF executable with information about the ABI it is compliant with. See the man page for &man.brandelf.1; for more information. FreeBSD comes from the classic camp and has traditionally used the &man.a.out.5; format, a technology tried and proven through many generations of BSD releases. Though it has also been possible for some time to build and run native ELF binaries (and kernels) on a FreeBSD system, FreeBSD initially resisted the push to switch to ELF as the default format. Why? Well, when the Linux camp made their painful transition to ELF, it was not so much to flee the a.out executable format as it was their inflexible jump-table based shared library mechanism, which made the construction of shared libraries very difficult for vendors and developers alike. Since the ELF tools available offered a solution to the shared library problem and were generally seen as the way forward anyway, the migration cost was accepted as necessary and the transition made. In FreeBSD's case, our shared library mechanism is based more closely on Sun's SunOS-style shared library mechanism and, as such, is very easy to use. However, starting with 3.0, FreeBSD officially supports ELF binaries as the default format. Even though the a.out executable format has served us well, the GNU people, who author the compiler tools we use, have dropped support for the a.out format. This has forced us to maintain a divergent version of the compiler and linker, and has kept us from reaping the benefits of the latest GNU development efforts. Also the demands of ISO-C++, notably constructors and destructors, has also led to native ELF support in future FreeBSD releases. Yes, but why are there so many different formats? Back in the dim, dark past, there was simple hardware. This simple hardware supported a simple, small system. a.out was completely adequate for the job of representing binaries on this simple system (a PDP-11). As people ported Unix from this simple system, they retained the a.out format because it was sufficient for the early ports of Unix to architectures like the Motorola 68k, VAXen, etc. Then some bright hardware engineer decided that if he could force software to do some sleazy tricks, then he would be able to shave a few gates off the design and allow his CPU core to run faster. While it was made to work with this new kind of hardware (known these days as RISC), a.out was ill-suited for this hardware, so many formats were developed to get to a better performance from this hardware than the limited, simple a.out format could offer. Things like COFF, ECOFF, and a few obscure others were invented and their limitations explored before things seemed to settle on ELF. In addition, program sizes were getting huge and disks (and physical memory) were still relatively small so the concept of a shared library was born. The VM system also became more sophisticated. While each one of these advancements was done using the a.out format, its usefulness was stretched more and more with each new feature. In addition, people wanted to dynamically load things at run time, or to junk parts of their program after the init code had run to save in core memory and/or swap space. Languages became more sophisticated and people wanted code called before main automatically. Lots of hacks were done to the a.out format to allow all of these things to happen, and they basically worked for a time. In time, a.out was not up to handling all these problems without an ever increasing overhead in code and complexity. While ELF solved many of these problems, it would be painful to switch from the system that basically worked. So ELF had to wait until it was more painful to remain with a.out than it was to migrate to ELF. However, as time passed, the build tools that FreeBSD derived their build tools from (the assembler and loader especially) evolved in two parallel trees. The FreeBSD tree added shared libraries and fixed some bugs. The GNU folks that originally write these programs rewrote them and added simpler support for building cross compilers, plugging in different formats at will, etc. Since many people wanted to build cross compilers targeting FreeBSD, they were out of luck since the older sources that FreeBSD had for as and ld were not up to the task. The new gnu tools chain (binutils) does support cross compiling, ELF, shared libraries, C++ extensions, etc. In addition, many vendors are releasing ELF binaries, and it is a good thing for FreeBSD to run them. And if it is running ELF binaries, why bother having a.out any more? It is a tired old horse that has proven useful for a long time, but it is time to turn him out to pasture for his long, faithful years of service. ELF is more expressive than a.out and will allow more extensibility in the base system. The ELF tools are better maintained, and offer cross compilation support, which is important to many people. ELF may be a little slower than a.out, but trying to measure it can be difficult. There are also numerous details that are different between the two in how they map pages, handle init code, etc. None of these are very important, but they are differences. In time support for a.out will be moved out of the GENERIC kernel, and eventually removed from the kernel once the need to run legacy a.out programs is past. Why will chmod not change the permissions on symlinks? Symlinks do not have permissions, and by default, &man.chmod.1; will not follow symlinks to change the permissions on the target file. So if you have a file, foo, and a symlink to that file, bar, then this command will always succeed. &prompt.user; chmod g-w bar However, the permissions on foo will not have changed. You have to use either or together with the option to make this work. See the &man.chmod.1; and &man.symlink.7; man pages for more info. The option does a RECURSIVE &man.chmod.1;. Be careful about specifying directories or symlinks to directories to &man.chmod.1;. If you want to change the permissions of a directory referenced by a symlink, use &man.chmod.1; without any options and follow the symlink with a trailing slash (/). For example, if foo is a symlink to directory bar, and you want to change the permissions of foo (actually bar), you would do something like: &prompt.user; chmod 555 foo/ With the trailing slash, &man.chmod.1; will follow the symlink, foo, to change the permissions of the directory, bar. Why are login names restricted to 8 characters or less in FreeBSD 2.2.X and earlier? You would think it would be easy enough to change UT_NAMESIZE and rebuild the whole world, and everything would just work. Unfortunately there are often scads of applications and utilities (including system tools) that have hard-coded small numbers (not always 8 or 9, but oddball ones like 15 and 20) in structures and buffers. Not only will this get you log files which are trashed (due to variable-length records getting written when fixed records were expected), but it can break Suns NIS clients and potentially cause other problems in interacting with other Unix systems. In FreeBSD 3.0 and later, the maximum name length has been increased to 16 characters and those various utilities with hard-coded name sizes have been found and fixed. The fact that this touched so many areas of the system is why, in fact, the change was not made until 3.0. If you are absolutely confident in your ability to find and fix these sorts of problems for yourself when and if they pop up, you can increase the login name length in earlier releases by editing /usr/include/utmp.h and changing UT_NAMESIZE accordingly. You must also update MAXLOGNAME in /usr/include/sys/param.h to match the UT_NAMESIZE change. Finally, if you build from sources, do not forget that /usr/include is updated each time! Change the appropriate files in /usr/src/.. instead. Can I run DOS binaries under FreeBSD? Yes, starting with version 3.0 you can using BSDI's doscmd DOS emulation which has been integrated and enhanced. Send mail to the &a.emulation; if you are interested in joining this ongoing effort! For pre-3.0 systems, there is a neat utility called pcemu in the ports collection which emulates an 8088 and enough BIOS services to run DOS text mode applications. It requires the X Window System (provided as XFree86). What do I need to do to translate a FreeBSD document into my native language? See the Translation FAQ in the FreeBSD Documentation Project Primer. Why does my email to any address at FreeBSD.org bounce? The FreeBSD.org mail system implements some of the stricter Postfix checks on incoming mail and rejects mail that is either misconfigured or is potential spam. Your mail might bounce for one of the following reasons: The email is being sent from a known spam domain or IP block. The FreeBSD mail servers reject email from known spam sources. If you have service through a company or domain who generates or relays spam, please switch to a service provider who does not. The body of the email only contains HTML. Mail should be sent in plain text only. Please configure your mail user agent to send plain text. The mailer at FreeBSD.org cannot resolve the IP address of the connecting host back to a symbolic name. Working reverse DNS is a standard requirement for accepting mail from a host. Set up reverse DNS for your mail server's IP address. Many home services (DSL, cable, dialup, etc.) will not give you this option. In this case, relay your email through your service provider's mail server. The hostname given in the EHLO/HELO part of the SMTP exchange cannot be resolved to an IP address. A fully qualified, resolvable host name is necessary in this part of the SMTP dialogue before mail will be accepted. If you do not have a host name that is registered in the DNS, then you should use your service provider's mail server to relay your mail. Your message had a message ID ending with the string localhost. Some mail user agents generate bad message IDs which will not be accepted. You will need to persuade your mail user agent to generate a valid message ID or else configure your mail transfer agent to rewrite them. Where can I find a free FreeBSD account? While FreeBSD does not provide open access to any of their servers, others do provide open access Unix systems. The charge varies and limited services may be available. Arbornet, Inc, also known as M-Net, has been providing open access to Unix systems since 1983. Starting on an Altos running System III, the site switched to BSD/OS in 1991. In June of 2000, the site switched again to FreeBSD. M-Net can be accessed via telnet and SSH and provides basic access to the entire FreeBSD software suite. However, network access is limited to members and patrons who donate to the system, which is run as a non-profit organization. M-Net also provides an bulletin board system and interactive chat. Grex provides a site very similar to M-Net including the same bulletin board and interactive chat software. However, the machine is a Sun 4M and is running SunOS What is sup, and how do I use it? SUP stands for Software Update Protocol, and was developed by CMU for keeping their development trees in sync. We used it to keep remote sites in sync with our central development sources. SUP is not bandwidth friendly, and has been retired. The current recommended method to keep your sources up to date is CVSup What is the cute little red guy's name? He does not have one, and is just called the BSD daemon. If you insist upon using a name, call him beastie. Note that beastie is pronounced BSD. You can learn more about the BSD daemon on his home page. Can I use the BSD daemon image? Perhaps. The BSD daemon is copyrighted by Marshall Kirk McKusick. You will want to check his Statement on the Use of the BSD Daemon Figure for detailed usage terms. In summary, you are free to use the image in a tasteful manner, for personal use, so long as appropriate credit is given. If you want to use him commercially, you must contact Kirk McKusick. More details are available on the BSD Daemon's home page. Do you have any BSD daemon images I could use? You will find eps and Xfig drawings under /usr/share/examples/BSD_daemon/. What does MFC mean? MFC is an acronym for Merged From -CURRENT. It is used in the CVS logs to denote when a change was migrated from the CURRENT to the STABLE branches. What does BSD mean? It stands for something in a secret language that only members can know. It does not translate literally but its ok to tell you that BSD's translation is something between, Formula-1 Racing Team, Penguins are tasty snacks, and We have a better sense of humor than Linux. :-) Seriously, BSD is an acronym for Berkeley Software Distribution, which is the name the Berkeley CSRG (Computer Systems Research Group) chose for their Unix distribution way back when. What does POLA mean? Principle of Least Astonishment. It means that as FreeBSD evolves, changes visible to the user should be kept as unsurprising as possible. For example, arbitrarily rearranging system startup variables in /etc/defaults/rc.conf violates POLA. Developers consider POLA when contemplating user-visible system changes. What is a repo-copy? A repo-copy (which is a short form of repository copy) refers to the direct copying of files within the CVS repository. Without a repo-copy, if a file needed to be copied or moved to another place in the repository, the committer would run cvs add to put the file in its new location, and then cvs rm on the old file if the old copy was being removed. The disadvantage of this method is that the history (i.e. the entries in the CVS logs) of the file would not be copied to the new location. As the FreeBSD Project considers this history very useful, a repository copy is often used instead. This is a process where one of the repository meisters will copy the files directly within the repository, rather than using the &man.cvs.1; program. Why should I care what color the bikeshed is? The really, really short answer is that you should not. The somewhat longer answer is that just because you are capable of building a bikeshed does not mean you should stop others from building one just because you do not like the color they plan to paint it. This is a metaphor indicating that you need not argue about every little feature just because you know enough to do so. Some people have commented that the amount of noise generated by a change is inversely proportional to the complexity of the change. The longer and more complete answer is that after a very long argument about whether &man.sleep.1; should take fractional second arguments, &a.phk; posted a long message entitled A bike shed (any colour will do) on greener grass.... The appropriate portions of that message are quoted below.
&a.phk; on freebsd-hackers, October 2, 1999 What is it about this bike shed? Some of you have asked me. It is a long story, or rather it is an old story, but it is quite short actually. C. Northcote Parkinson wrote a book in the early 1960s, called Parkinson's Law, which contains a lot of insight into the dynamics of management. [snip a bit of commentary on the book] In the specific example involving the bike shed, the other vital component is an atomic power-plant, I guess that illustrates the age of the book. Parkinson shows how you can go in to the board of directors and get approval for building a multi-million or even billion dollar atomic power plant, but if you want to build a bike shed you will be tangled up in endless discussions. Parkinson explains that this is because an atomic plant is so vast, so expensive and so complicated that people cannot grasp it, and rather than try, they fall back on the assumption that somebody else checked all the details before it got this far. Richard P. Feynmann gives a couple of interesting, and very much to the point, examples relating to Los Alamos in his books. A bike shed on the other hand. Anyone can build one of those over a weekend, and still have time to watch the game on TV. So no matter how well prepared, no matter how reasonable you are with your proposal, somebody will seize the chance to show that he is doing his job, that he is paying attention, that he is here. In Denmark we call it setting your fingerprint. It is about personal pride and prestige, it is about being able to point somewhere and say There! I did that. It is a strong trait in politicians, but present in most people given the chance. Just think about footsteps in wet cement.
The FreeBSD Funnies How cool is FreeBSD? Q. Has anyone done any temperature testing while running FreeBSD? I know Linux runs cooler than DOS, but have never seen a mention of FreeBSD. It seems to run really hot. A. No, but we have done numerous taste tests on blindfolded volunteers who have also had 250 micrograms of LSD-25 administered beforehand. 35% of the volunteers said that FreeBSD tasted sort of orange, whereas Linux tasted like purple haze. Neither group mentioned any significant variances in temperature. We eventually had to throw the results of this survey out entirely anyway when we found that too many volunteers were wandering out of the room during the tests, thus skewing the results. We think most of the volunteers are at Apple now, working on their new scratch and sniff GUI. It is a funny old business we are in! Seriously, both FreeBSD and Linux use the HLT (halt) instruction when the system is idle thus lowering its energy consumption and therefore the heat it generates. Also if you have APM (advanced power management) configured, then FreeBSD can also put the CPU into a low power mode. Who is scratching in my memory banks?? Q. Is there anything odd that FreeBSD does when compiling the kernel which would cause the memory to make a scratchy sound? When compiling (and for a brief moment after recognizing the floppy drive upon startup, as well), a strange scratchy sound emanates from what appears to be the memory banks. A. Yes! You will see frequent references to daemons in the BSD documentation, and what most people do not know is that this refers to genuine, non-corporeal entities that now possess your computer. The scratchy sound coming from your memory is actually high-pitched whispering exchanged among the daemons as they best decide how to deal with various system administration tasks. If the noise gets to you, a good fdisk /mbr from DOS will get rid of them, but do not be surprised if they react adversely and try to stop you. In fact, if at any point during the exercise you hear the satanic voice of Bill Gates coming from the built-in speaker, take off running and do not ever look back! Freed from the counterbalancing influence of the BSD daemons, the twin demons of DOS and Windows are often able to re-assert total control over your machine to the eternal damnation of your soul. Now that you know, given a choice you would probably prefer to get used to the scratchy noises, no? How many FreeBSD hackers does it take to change a lightbulb? One thousand, one hundred and seventy-two: Twenty-three to complain to -CURRENT about the lights being out; Four to claim that it is a configuration problem, and that such matters really belong on -questions; Three to submit PRs about it, one of which is misfiled under doc and consists only of "it's dark"; One to commit an untested lightbulb which breaks buildworld, then back it out five minutes later; Eight to flame the PR originators for not including patches in their PRs; Five to complain about buildworld being broken; Thirty-one to answer that it works for them, and they must have cvsupped at a bad time; One to post a patch for a new lightbulb to -hackers; One to complain that he had patches for this three years ago, but when he sent them to -CURRENT they were just ignored, and he has had bad experiences with the PR system; besides, the proposed new lightbulb is non-reflexive; Thirty-seven to scream that lightbulbs do not belong in the base system, that committers have no right to do things like this without consulting the Community, and WHAT IS -CORE DOING ABOUT IT!? Two hundred to complain about the color of the bicycle shed; Three to point out that the patch breaks &man.style.9;; Seventeen to complain that the proposed new lightbulb is under GPL; Five hundred and eighty-six to engage in a flame war about the comparative advantages of the GPL, the BSD license, the MIT license, the NPL, and the personal hygiene of unnamed FSF founders; Seven to move various portions of the thread to -chat and -advocacy; One to commit the suggested lightbulb, even though it shines dimmer than the old one; Two to back it out with a furious flame of a commit message, arguing that FreeBSD is better off in the dark than with a dim lightbulb; Forty-six to argue vociferously about the backing out of the dim lightbulb and demanding a statement from -core; Eleven to request a smaller lightbulb so it will fit their Tamagotchi if we ever decide to port FreeBSD to that platform; Seventy-three to complain about the SNR on -hackers and -chat and unsubscribe in protest; Thirteen to post "unsubscribe", "How do I unsubscribe?", or "Please remove me from the list", followed by the usual footer; One to commit a working lightbulb while everybody is too busy flaming everybody else to notice; Thirty-one to point out that the new lightbulb would shine 0.364% brighter if compiled with TenDRA (although it will have to be reshaped into a cube), and that FreeBSD should therefore switch to TenDRA instead of GCC; One to complain that the new lightbulb lacks fairings; Nine (including the PR originators) to ask "what is MFC?"; Fifty-seven to complain about the lights being out two weeks after the bulb has been changed. &a.nik; adds: I was laughing quite hard at this. And then I thought, "Hang on, shouldn't there be '1 to document it.' in that list somewhere?" And then I was enlightened :-) Where does data written to /dev/null go? It goes into a special data sink in the CPU where it is converted to heat which is vented through the heatsink / fan assembly. This is why CPU cooling is increasingly important; as people get used to faster processors, they become careless with their data and more and more of it ends up in /dev/null, overheating their CPUs. If you delete /dev/null (which effectively disables the CPU data sink) your CPU may run cooler but your system will quickly become constipated with all that excess data and start to behave erratically. If you have a fast network connection you can cool down your CPU by reading data out of /dev/random and sending it off somewhere; however you run the risk of overheating your network connection and / or angering your ISP, as most of the data will end up getting converted to heat by their equipment, but they generally have good cooling, so if you do not overdo it you should be OK. Paul Robinson adds: There are other methods. As every good sysadmin knows, it is part of standard practise to send data to the screen of interesting variety to keep all the pixies that make up your picture happy. Screen pixies (commonly mis-typed or re-named as 'pixels') are categorised by the type of hat they wear (red, green or blue) and will hide or appear (thereby showing the colour of their hat) whenever they receive a little piece of food. Video cards turn data into pixie-food, and then send them to the pixies - the more expensive the card, the better the food, so the better behaved the pixies are. They also need constant simulation - this is why screen savers exist. To take your suggestions further, you could just throw the random data to console, thereby letting the pixies consume it. This causes no heat to be produced at all, keeps the pixies happy and gets rid of your data quite quickly, even if it does make things look a bit messy on your screen. Incidentally, as an ex-admin of a large ISP who experienced many problems attempting to maintain a stable temperature in a server room, I would strongly discourage people sending the data they do not want out to the network. The fairies who do the packet switching and routing get annoyed by it as well. Advanced Topics How can I learn more about FreeBSD's internals? At this time, there is no book on FreeBSD-specific OS internals. Much general UNIX knowledge is directly applicable to FreeBSD, however. Additionally, there are BSD-specific books that are still relevant. For a list, please check the Handbook's Operating System Internals Bibliography. How can I contribute to FreeBSD? Please see the article on Contributing to FreeBSD for specific advice on how to do this. Assistance is more than welcome! What are SNAPs and RELEASEs? There are currently three active/semi-active branches in the FreeBSD CVS Repository (the RELENG_2 branch is probably only changed twice a year, which is why there are only three active branches of development): RELENG_2_2 AKA 2.2-STABLE RELENG_3 AKA 3.X-STABLE RELENG_4 AKA 4-STABLE HEAD AKA -CURRENT AKA 5.0-CURRENT HEAD is not an actual branch tag, like the other two; it is simply a symbolic constant for the current, non-branched development stream which we simply refer to as -CURRENT. Right now, -CURRENT is the 5.0 development stream and the 4-STABLE branch, RELENG_4, forked off from -CURRENT in Mar 2000. The 2.2-STABLE branch, RELENG_2_2, departed -CURRENT in November 1996, and has pretty much been retired. How do I make my own custom release? Please see the Release Engineering article. Why does make world clobber my existing installed binaries? Yes, this is the general idea; as its name might suggest, make world rebuilds every system binary from scratch, so you can be certain of having a clean and consistent environment at the end (which is why it takes so long). If the environment variable DESTDIR is defined while running make world or make install, the newly-created binaries will be deposited in a directory tree identical to the installed one, rooted at ${DESTDIR}. Some random combination of shared libraries modifications and program rebuilds can cause this to fail in make world however. Why does my system say (bus speed defaulted) when it boots? The Adaptec 1542 SCSI host adapters allow the user to configure their bus access speed in software. Previous versions of the 1542 driver tried to determine the fastest usable speed and set the adapter to that. We found that this breaks some users' systems, so you now have to define the TUNE_1542 kernel configuration option in order to have this take place. Using it on those systems where it works may make your disks run faster, but on those systems where it does not, your data could be corrupted. Can I follow current with limited Internet access? Yes, you can do this without downloading the whole source tree by using the CTM facility. How did you split the distribution into 240k files? Newer BSD based systems have a option to split that allows them to split files on arbitrary byte boundaries. Here is an example from /usr/src/Makefile. bin-tarball: (cd ${DISTDIR}; \ tar cf - . \ gzip --no-name -9 -c | \ split -b 240640 - \ ${RELEASEDIR}/tarballs/bindist/bin_tgz.) I have written a kernel extension, who do I send it to? Please take a look at the article on Contributing to FreeBSD to learn how to submit code. And thanks for the thought! How are Plug N Play ISA cards detected and initialized? By: Frank Durda IV uhclem@nemesis.lonestar.org In a nutshell, there a few I/O ports that all of the PnP boards respond to when the host asks if anyone is out there. So when the PnP probe routine starts, he asks if there are any PnP boards present, and all the PnP boards respond with their model # to a I/O read of the same port, so the probe routine gets a wired-OR yes to that question. At least one bit will be on in that reply. Then the probe code is able to cause boards with board model IDs (assigned by Microsoft/Intel) lower than X to go off-line. It then looks to see if any boards are still responding to the query. If the answer was 0, then there are no boards with IDs above X. Now probe asks if there are any boards below X. If so, probe knows there are boards with a model numbers below X. Probe then asks for boards greater than X-(limit/4) to go off-line. If repeats the query. By repeating this semi-binary search of IDs-in-range enough times, the probing code will eventually identify all PnP boards present in a given machine with a number of iterations that is much lower than what 2^64 would take. The IDs are two 32-bit fields (hence 2ˆ64) + 8 bit checksum. The first 32 bits are a vendor identifier. They never come out and say it, but it appears to be assumed that different types of boards from the same vendor could have different 32-bit vendor ids. The idea of needing 32 bits just for unique manufacturers is a bit excessive. The lower 32 bits are a serial #, Ethernet address, something that makes this one board unique. The vendor must never produce a second board that has the same lower 32 bits unless the upper 32 bits are also different. So you can have multiple boards of the same type in the machine and the full 64 bits will still be unique. The 32 bit groups can never be all zero. This allows the wired-OR to show non-zero bits during the initial binary search. Once the system has identified all the board IDs present, it will reactivate each board, one at a time (via the same I/O ports), and find out what resources the given board needs, what interrupt choices are available, etc. A scan is made over all the boards to collect this information. This info is then combined with info from any ECU files on the hard disk or wired into the MLB BIOS. The ECU and BIOS PnP support for hardware on the MLB is usually synthetic, and the peripherals do not really do genuine PnP. However by examining the BIOS info plus the ECU info, the probe routines can cause the devices that are PnP to avoid those devices the probe code cannot relocate. Then the PnP devices are visited once more and given their I/O, DMA, IRQ and Memory-map address assignments. The devices will then appear at those locations and remain there until the next reboot, although there is nothing that says you cannot move them around whenever you want. There is a lot of oversimplification above, but you should get the general idea. Microsoft took over some of the primary printer status ports to do PnP, on the logic that no boards decoded those addresses for the opposing I/O cycles. I found a genuine IBM printer board that did decode writes of the status port during the early PnP proposal review period, but MS said tough. So they do a write to the printer status port for setting addresses, plus that use that address + 0x800, and a third I/O port for reading that can be located anywhere between 0x200 and 0x3ff. Can you assign a major number for a device driver I have written? This depends on whether or not you plan on making the driver publicly available. If you do, then please send us a copy of the driver source code, plus the appropriate modifications to files.i386, a sample configuration file entry, and the appropriate &man.MAKEDEV.8; code to create any special files your device uses. If you do not, or are unable to because of licensing restrictions, then character major number 32 and block major number 8 have been reserved specifically for this purpose; please use them. In any case, we would appreciate hearing about your driver on &a.hackers;. What about alternative layout policies for directories? In answer to the question of alternative layout policies for directories, the scheme that is currently in use is unchanged from what I wrote in 1983. I wrote that policy for the original fast filesystem, and never revisited it. It works well at keeping cylinder groups from filling up. As several of you have noted, it works poorly for find. Most filesystems are created from archives that were created by a depth first search (aka ftw). These directories end up being striped across the cylinder groups thus creating a worst possible scenario for future depth first searches. If one knew the total number of directories to be created, the solution would be to create (total / fs_ncg) per cylinder group before moving on. Obviously, one would have to create some heuristic to guess at this number. Even using a small fixed number like say 10 would make an order of magnitude improvement. To differentiate restores from normal operation (when the current algorithm is probably more sensible), you could use the clustering of up to 10 if they were all done within a ten second window. Anyway, my conclusion is that this is an area ripe for experimentation. Kirk McKusick, September 1998 How can I make the most of the data I see when my kernel panics? [This section was extracted from a mail written by &a.wpaul; on the freebsd-current mailing list by &a.des;, who fixed a few typos and added the bracketed comments] From: Bill Paul <wpaul@skynet.ctr.columbia.edu> Subject: Re: the fs fun never stops To: Ben Rosengart Date: Sun, 20 Sep 1998 15:22:50 -0400 (EDT) Cc: current@FreeBSD.org Ben Rosengart posted the following panic message] > Fatal trap 12: page fault while in kernel mode > fault virtual address = 0x40 > fault code = supervisor read, page not present > instruction pointer = 0x8:0xf014a7e5 ^^^^^^^^^^ > stack pointer = 0x10:0xf4ed6f24 > frame pointer = 0x10:0xf4ed6f28 > code segment = base 0x0, limit 0xfffff, type 0x1b > = DPL 0, pres 1, def32 1, gran 1 > processor eflags = interrupt enabled, resume, IOPL = 0 > current process = 80 (mount) > interrupt mask = > trap number = 12 > panic: page fault [When] you see a message like this, it is not enough to just reproduce it and send it in. The instruction pointer value that I highlighted up there is important; unfortunately, it is also configuration dependent. In other words, the value varies depending on the exact kernel image that you are using. If you are using a GENERIC kernel image from one of the snapshots, then it is possible for somebody else to track down the offending function, but if you are running a custom kernel then only you can tell us where the fault occurred. What you should do is this: Write down the instruction pointer value. Note that the 0x8: part at the beginning is not significant in this case: it is the 0xf0xxxxxx part that we want. When the system reboots, do the following: &prompt.user; nm -n /kernel.that.caused.the.panic | grep f0xxxxxx where f0xxxxxx is the instruction pointer value. The odds are you will not get an exact match since the symbols in the kernel symbol table are for the entry points of functions and the instruction pointer address will be somewhere inside a function, not at the start. If you do not get an exact match, omit the last digit from the instruction pointer value and try again, i.e.: &prompt.user; nm -n /kernel.that.caused.the.panic | grep f0xxxxx If that does not yield any results, chop off another digit. Repeat until you get some sort of output. The result will be a possible list of functions which caused the panic. This is a less than exact mechanism for tracking down the point of failure, but it is better than nothing. I see people constantly show panic messages like this but rarely do I see someone take the time to match up the instruction pointer with a function in the kernel symbol table. The best way to track down the cause of a panic is by capturing a crash dump, then using &man.gdb.1; to generate a stack trace on the crash dump. In any case, the method I normally use is this: Set up a kernel config file, optionally adding options DDB if you think you need the kernel debugger for something. (I use this mainly for setting breakpoints if I suspect an infinite loop condition of some kind.) Use config -g KERNELCONFIG to set up the build directory. cd /sys/compile/ KERNELCONFIG; make Wait for kernel to finish compiling. make install reboot The &man.make.1; process will have built two kernels. kernel and kernel.debug. kernel was installed as /kernel, while kernel.debug can be used as the source of debugging symbols for &man.gdb.1;. To make sure you capture a crash dump, you need edit /etc/rc.conf and set dumpdev to point to your swap partition. This will cause the &man.rc.8; scripts to use the &man.dumpon.8; command to enable crash dumps. You can also run &man.dumpon.8; manually. After a panic, the crash dump can be recovered using &man.savecore.8;; if dumpdev is set in /etc/rc.conf, the &man.rc.8; scripts will run &man.savecore.8; automatically and put the crash dump in /var/crash. FreeBSD crash dumps are usually the same size as the physical RAM size of your machine. That is, if you have 64MB of RAM, you will get a 64MB crash dump. Therefore you must make sure there is enough space in /var/crash to hold the dump. Alternatively, you run &man.savecore.8; manually and have it recover the crash dump to another directory where you have more room. It is possible to limit the size of the crash dump by using options MAXMEM=(foo) to set the amount of memory the kernel will use to something a little more sensible. For example, if you have 128MB of RAM, you can limit the kernel's memory usage to 16MB so that your crash dump size will be 16MB instead of 128MB. Once you have recovered the crash dump, you can get a stack trace with &man.gdb.1; as follows: &prompt.user; gdb -k /sys/compile/KERNELCONFIG/kernel.debug /var/crash/vmcore.0 (gdb) where Note that there may be several screens worth of information; ideally you should use &man.script.1; to capture all of them. Using the unstripped kernel image with all the debug symbols should show the exact line of kernel source code where the panic occurred. Usually you have to read the stack trace from the bottom up in order to trace the exact sequence of events that lead to the crash. You can also use &man.gdb.1; to print out the contents of various variables or structures in order to examine the system state at the time of the crash. Now, if you are really insane and have a second computer, you can also configure &man.gdb.1; to do remote debugging such that you can use &man.gdb.1; on one system to debug the kernel on another system, including setting breakpoints, single-stepping through the kernel code, just like you can do with a normal user-mode program. I have not played with this yet as I do not often have the chance to set up two machines side by side for debugging purposes. [Bill adds: "I forgot to mention one thing: if you have DDB enabled and the kernel drops into the debugger, you can force a panic (and a crash dump) just by typing 'panic' at the ddb prompt. It may stop in the debugger again during the panic phase. If it does, type 'continue' and it will finish the crash dump." -ed] Why has dlsym() stopped working for ELF executables? The ELF toolchain does not, by default, make the symbols defined in an executable visible to the dynamic linker. Consequently dlsym() searches on handles obtained from calls to dlopen(NULL, flags) will fail to find such symbols. If you want to search, using dlsym(), for symbols present in the main executable of a process, you need to link the executable using the option to the ELF linker (&man.ld.1;). How can I increase or reduce the kernel address space? By default, the kernel address space is 256 MB on FreeBSD 3.x and 1 GB on FreeBSD 4.x. If you run a network-intensive server (e.g. a large FTP or HTTP server), you might find that 256 MB is not enough. So how do you increase the address space? There are two aspects to this. First, you need to tell the kernel to reserve a larger portion of the address space for itself. Second, since the kernel is loaded at the top of the address space, you need to lower the load address so it does not bump its head against the ceiling. The first goal is achieved by increasing the value of NKPDE in src/sys/i386/include/pmap.h. Here is what it looks like for a 1 GB address space: #ifndef NKPDE #ifdef SMP #define NKPDE 254 /* addressable number of page tables/pde's */ #else #define NKPDE 255 /* addressable number of page tables/pde's */ #endif /* SMP */ #endif To find the correct value of NKPDE, divide the desired address space size (in megabytes) by four, then subtract one for UP and two for SMP. To achieve the second goal, you need to compute the correct load address: simply subtract the address space size (in bytes) from 0x100100000; the result is 0xc0100000 for a 1 GB address space. Set LOAD_ADDRESS in src/sys/i386/conf/Makefile.i386 to that value; then set the location counter in the beginning of the section listing in src/sys/i386/conf/kernel.script to the same value, as follows: OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386") OUTPUT_ARCH(i386) ENTRY(btext) SEARCH_DIR(/usr/lib); SEARCH_DIR(/usr/obj/elf/home/src/tmp/usr/i386-unknown-freebsdelf/lib); SECTIONS { /* Read-only sections, merged into text segment: */ . = 0xc0100000 + SIZEOF_HEADERS; .interp : { *(.interp) } Then reconfig and rebuild your kernel. You will probably have problems with &man.ps.1; &man.top.1; and the like; make world should take care of it (or a manual rebuild of libkvm, &man.ps.1; and &man.top.1; after copying the patched pmap.h to /usr/include/vm/. NOTE: the size of the kernel address space must be a multiple of four megabytes. [&a.dg; adds: I think the kernel address space needs to be a power of two, but I am not certain about that. The old(er) boot code used to monkey with the high order address bits and I think expected at least 256MB granularity.] Acknowledgments
FreeBSD Core Team If you see a problem with this FAQ, or wish to submit an entry, please mail the &a.faq;. We appreciate your feedback, and cannot make this a better FAQ without your help!
&a.jkh; Occasional fits of FAQ-reshuffling and updating. &a.dwhite; Services above and beyond the call of duty on freebsd-questions &a.joerg; Services above and beyond the call of duty on Usenet &a.wollman; Networking and formatting Jim Lowe Multicast information &a.pds; FreeBSD FAQ typing machine slavey The FreeBSD Team Kvetching, moaning, submitting data And to any others we have forgotten, apologies and heartfelt thanks! &bibliography; diff --git a/en_US.ISO8859-1/books/handbook/advanced-networking/chapter.sgml b/en_US.ISO8859-1/books/handbook/advanced-networking/chapter.sgml index fcbfe82957..a8664b7f82 100644 --- a/en_US.ISO8859-1/books/handbook/advanced-networking/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/advanced-networking/chapter.sgml @@ -1,5898 +1,5898 @@ Advanced Networking Synopsis This chapter will cover some of the more frequently used network services on Unix systems. We will cover how to define, setup, test and maintain all of the network services that FreeBSD utilizes. In addition, there have been example configuration files included throughout this chapter for you to benefit from. After reading this chapter, you will know: The basics of gateways and routes. How to make FreeBSD act as a bridge. - How to setup a network file system. + How to setup a network filesystem. How to setup network booting on a diskless machine. How to setup a network information server for sharing user accounts. How to setup automatic network settings using DHCP. How to setup a domain name server. How to synchronize the time and date, and setup a time server, with the NTP protocol. How to setup network address translation. How to manage the inetd daemon. How to connect two computers via PLIP. Before reading this chapter, you should: Understand the basics of the /etc/rc scripts. Be familiar with basic network terminology. Coranth Gryphon Contributed by Gateways and Routes routing gateway subnet For one machine to be able to find another over a network, there must be a mechanism in place to describe how to get from one to the other. This is called routing. A route is a defined pair of addresses: a destination and a gateway. The pair indicates that if you are trying to get to this destination, communicate through this gateway. There are three types of destinations: individual hosts, subnets, and default. The default route is used if none of the other routes apply. We will talk a little bit more about default routes later on. There are also three types of gateways: individual hosts, interfaces (also called links), and Ethernet hardware addresses (MAC addresses). An Example To illustrate different aspects of routing, we will use the following example from netstat: &prompt.user; netstat -r Routing tables Destination Gateway Flags Refs Use Netif Expire default outside-gw UGSc 37 418 ppp0 localhost localhost UH 0 181 lo0 test0 0:e0:b5:36:cf:4f UHLW 5 63288 ed0 77 10.20.30.255 link#1 UHLW 1 2421 example.com link#1 UC 0 0 host1 0:e0:a8:37:8:1e UHLW 3 4601 lo0 host2 0:e0:a8:37:8:1e UHLW 0 5 lo0 => host2.example.com link#1 UC 0 0 224 link#1 UC 0 0 default route The first two lines specify the default route (which we will cover in the next section) and the localhost route. loopback device The interface (Netif column) that it specifies to use for localhost is lo0, also known as the loopback device. This says to keep all traffic for this destination internal, rather than sending it out over the LAN, since it will only end up back where it started. Ethernet MAC address The next thing that stands out are the addresses beginning with 0:e0:. These are Ethernet hardware addresses, which are also known as MAC addresses. FreeBSD will automatically identify any hosts (test0 in the example) on the local Ethernet and add a route for that host, directly to it over the Ethernet interface, ed0. There is also a timeout (Expire column) associated with this type of route, which is used if we fail to hear from the host in a specific amount of time. In this case the route will be automatically deleted. These hosts are identified using a mechanism known as RIP (Routing Information Protocol), which figures out routes to local hosts based upon a shortest path determination. subnet FreeBSD will also add subnet routes for the local subnet (10.20.30.255 is the broadcast address for the subnet 10.20.30, and example.com is the domain name associated with that subnet). The designation link#1 refers to the first Ethernet card in the machine. You will notice no additional interface is specified for those. Both of these groups (local network hosts and local subnets) have their routes automatically configured by a daemon called routed. If this is not run, then only routes which are statically defined (i.e. entered explicitly) will exist. The host1 line refers to our host, which it knows by Ethernet address. Since we are the sending host, FreeBSD knows to use the loopback interface (lo0) rather than sending it out over the Ethernet interface. The two host2 lines are an example of what happens when we use an &man.ifconfig.8; alias (see the section on Ethernet for reasons why we would do this). The => symbol after the lo0 interface says that not only are we using the loopback (since this address also refers to the local host), but specifically it is an alias. Such routes only show up on the host that supports the alias; all other hosts on the local network will simply have a link#1 line for such. The final line (destination subnet 224) deals with MultiCasting, which will be covered in another section. The other column that we should talk about are the Flags. Each route has different attributes that are described in the column. Below is a short table of some of these flags and their meanings: U Up: The route is active. H Host: The route destination is a single host. G Gateway: Send anything for this destination on to this remote system, which will figure out from there where to send it. S Static: This route was configured manually, not automatically generated by the system. C Clone: Generates a new route based upon this route for machines we connect to. This type of route is normally used for local networks. W WasCloned: Indicated a route that was auto-configured based upon a local area network (Clone) route. L Link: Route involves references to Ethernet hardware. Default Routes default route When the local system needs to make a connection to a remote host, it checks the routing table to determine if a known path exists. If the remote host falls into a subnet that we know how to reach (Cloned routes), then the system checks to see if it can connect along that interface. If all known paths fail, the system has one last option: the default route. This route is a special type of gateway route (usually the only one present in the system), and is always marked with a c in the flags field. For hosts on a local area network, this gateway is set to whatever machine has a direct connection to the outside world (whether via PPP link, DSL, cable modem, T1, or another network interface). If you are configuring the default route for a machine which itself is functioning as the gateway to the outside world, then the default route will be the gateway machine at your Internet Service Provider's (ISP) site. Let us look at an example of default routes. This is a common configuration: [Local2] <--ether--> [Local1] <--PPP--> [ISP-Serv] <--ether--> [T1-GW] The hosts Local1 and Local2 are at your site. Local1 is connected to an ISP via a dial up PPP connection. This PPP server computer is connected through a local area network to another gateway computer with an external interface to the ISPs Internet feed. The default routes for each of your machines will be: Host Default Gateway Interface Local2 Local1 Ethernet Local1 T1-GW PPP A common question is Why (or how) would we set the T1-GW to be the default gateway for Local1, rather than the ISP server it is connected to?. Remember, since the PPP interface is using an address on the ISP's local network for your side of the connection, routes for any other machines on the ISP's local network will be automatically generated. Hence, you will already know how to reach the T1-GW machine, so there is no need for the intermediate step of sending traffic to the ISP server. As a final note, it is common to use the address X.X.X.1 as the gateway address for your local network. So (using the same example), if your local class-C address space was 10.20.30 and your ISP was using 10.9.9 then the default routes would be: Host Default Route Local2 (10.20.3.2) Local1 (10.20.30.1) Local1 (10.20.30.1, 10.9.9.30) T1-GW (10.9.9.1) Dual Homed Hosts dual homed hosts There is one other type of configuration that we should cover, and that is a host that sits on two different networks. Technically, any machine functioning as a gateway (in the example above, using a PPP connection) counts as a dual-homed host. But the term is really only used to refer to a machine that sits on two local-area networks. In one case, the machine has two Ethernet cards, each having an address on the separate subnets. Alternately, the machine may only have one Ethernet card, and be using &man.ifconfig.8; aliasing. The former is used if two physically separate Ethernet networks are in use, the latter if there is one physical network segment, but two logically separate subnets. Either way, routing tables are set up so that each subnet knows that this machine is the defined gateway (inbound route) to the other subnet. This configuration, with the machine acting as a router between the two subnets, is often used when we need to implement packet filtering or firewall security in either or both directions. If you want this machine to actually forward packets between the two interfaces, you need to tell FreeBSD to enable this ability. Building a Router router A network router is simply a system that forwards packets from one interface to another. Internet standards and good engineering practice prevent the FreeBSD Project from enabling this by default in FreeBSD. You can enable this feature by changing the following variable to YES in &man.rc.conf.5;: gateway_enable=YES # Set to YES if this host will be a gateway This option will set the &man.sysctl.8; variable net.inet.ip.forwarding to 1. If you should need to stop routing temporarily, you can reset this to 0 temporarily. Your new router will need routes to know where to send the traffic. If your network is simple enough you can use static routes. FreeBSD also comes with the standard BSD routing daemon &man.routed.8;, which speaks RIP (both version 1 and version 2) and IRDP. For more complex situations you may want to try net/gated. Even when FreeBSD is configured in this way, it does not completely comply with the Internet standard requirements for routers. It comes close enough for ordinary use, however. Routing Propagation routing propagation We have already talked about how we define our routes to the outside world, but not about how the outside world finds us. We already know that routing tables can be set up so that all traffic for a particular address space (in our examples, a class-C subnet) can be sent to a particular host on that network, which will forward the packets inbound. When you get an address space assigned to your site, your service provider will set up their routing tables so that all traffic for your subnet will be sent down your PPP link to your site. But how do sites across the country know to send to your ISP? There is a system (much like the distributed DNS information) that keeps track of all assigned address-spaces, and defines their point of connection to the Internet Backbone. The Backbone are the main trunk lines that carry Internet traffic across the country, and around the world. Each backbone machine has a copy of a master set of tables, which direct traffic for a particular network to a specific backbone carrier, and from there down the chain of service providers until it reaches your network. It is the task of your service provider to advertise to the backbone sites that they are the point of connection (and thus the path inward) for your site. This is known as route propagation. Troubleshooting traceroute Sometimes, there is a problem with routing propagation, and some sites are unable to connect to you. Perhaps the most useful command for trying to figure out where routing is breaking down is the &man.traceroute.8; command. It is equally useful if you cannot seem to make a connection to a remote machine (i.e. &man.ping.8; fails). The &man.traceroute.8; command is run with the name of the remote host you are trying to connect to. It will show the gateway hosts along the path of the attempt, eventually either reaching the target host, or terminating because of a lack of connection. For more information, see the manual page for &man.traceroute.8;. Steve Peterson Written by Bridging Introduction IP subnet bridge It is sometimes useful to divide one physical network (such as an Ethernet segment) into two separate network segments without having to create IP subnets and use a router to connect the segments together. A device that connects two networks together in this fashion is called a bridge. A FreeBSD system with two network interface cards can act as a bridge. The bridge works by learning the MAC layer addresses (Ethernet addresses) of the devices on each of its network interfaces. It forwards traffic between two networks only when its source and destination are on different networks. In many respects, a bridge is like an Ethernet switch with very few ports. Situations Where Bridging Is Appropriate There are two common situations in which a bridge is used today. High Traffic on a Segment Situation one is where your physical network segment is overloaded with traffic, but you do not want for whatever reason to subnet the network and interconnect the subnets with a router. Let us consider an example of a newspaper where the Editorial and Production departments are on the same subnetwork. The Editorial users all use server A for file service, and the Production users are on server B. An Ethernet is used to connect all users together, and high loads on the network are slowing things down. If the Editorial users could be segregated on one network segment and the Production users on another, the two network segments could be connected with a bridge. Only the network traffic destined for interfaces on the "other" side of the bridge would be sent to the other network, reducing congestion on each network segment. Filtering/Traffic Shaping Firewall firewall IP Masquerading The second common situation is where firewall functionality is needed without IP Masquerading (NAT). An example is a small company that is connected via DSL or ISDN to their ISP. They have a 13 globally-accessible IP addresses from their ISP and have 10 PCs on their network. In this situation, using a router-based firewall is difficult because of subnetting issues. router DSL ISDN A bridge-based firewall can be configured and dropped into the path just downstream of their DSL/ISDN router without any IP numbering issues. Configuring a Bridge Network Interface Card Selection A bridge requires at least two network cards to function. Unfortunately, not all network interface cards as of FreeBSD 4.0 support bridging. Read &man.bridge.4; for details on the cards that are supported. Install and test the two network cards before continuing. Kernel Configuration Changes kernel configuration kernel configuration options BRIDGE To enable kernel support for bridging, add the: options BRIDGE statement to your kernel configuration file, and rebuild your kernel. Firewall Support firewall If you are planning to use the bridge as a firewall, you will need to add the IPFIREWALL option as well. Read for general information on configuring the bridge as a firewall. If you need to allow non-IP packets (such as ARP) to flow through the bridge, there is an undocumented firewall option that must be set. This option is IPFIREWALL_DEFAULT_TO_ACCEPT. Note that this changes the default rule for the firewall to accept any packet. Make sure you know how this changes the meaning of your ruleset before you set it. Traffic Shaping Support If you want to use the bridge as a traffic shaper, you will need to add the DUMMYNET option to your kernel configuration. Read &man.dummynet.4; for further information. Enabling the Bridge Add the line: net.link.ether.bridge=1 to /etc/sysctl.conf to enable the bridge at runtime. If you want the bridged packets to be filtered by &man.ipfw.8;, you should add: net.link.ether.bridge_ipfw=1 as well. Performance My bridge/firewall is a Pentium 90 with one 3Com 3C900B and one 3C905B. The protected side of the network runs at 10mbps half duplex and the connection between the bridge and my router (a Cisco 675) runs at 100mbps full duplex. With no filtering enabled, I have found that the bridge adds about 0.4 milliseconds of latency to pings from the protected 10mbps network to the Cisco 675. Other Information If you want to be able to telnet into the bridge from the network, it is OK to assign one of the network cards an IP address. The consensus is that assigning both cards an address is a bad idea. If you have multiple bridges on your network, there cannot be more than one path between any two workstations. Technically, this means that there is no support for spanning tree link management. Tom Rhodes Reorganized and enhanced by Bill Swingle Written by NFS NFS - Among the many different file systems that FreeBSD supports is + Among the many different filesystems that FreeBSD supports is the Network File System, also known as NFS. NFS allows a system to share directories and files with others over a network. By using NFS, users and programs can access files on remote systems almost as if they were local files. Some of the most notable benefits that NFS can provide are: Local workstations use less disk space because commonly used data can be stored on a single machine and still remain accessible to others over the network. There is no need for users to have separate home directories on every network machine. Home directories could be setup on the NFS server and made available throughout the network. Storage devices such as floppy disks, CDROM drives, and ZIP drives can be used by other machines on the network. This may reduce the number of removable media drives throughout the network. How <acronym>NFS</acronym> Works NFS consists of at least two main parts: a server and one or more clients. The client remotely accesses the data that is stored on the server machine. In order for this to function properly a few processes have to be configured and running: The server has to be running the following daemons: NFS server portmap mountd nfsd Daemon Description nfsd The NFS daemon which services requests from the NFS clients. mountd The NFS mount daemon which carries out the requests that &man.nfsd.8; passes on to it. portmap The portmapper daemon allows NFS clients to discover which port the NFS server is using. The client can also run a daemon, known as nfsiod. The nfsiod daemon services the requests from the NFS server. This is optional, and improves performance, but is not required for normal and correct operation. See the &man.nfsiod.8; manual page for more information. Configuring <acronym>NFS</acronym> NFS configuration NFS configuration is a relatively straightforward process. The processes that need to be running can all start at boot time with a few modifications to your /etc/rc.conf file. On the NFS server, make sure that the following options are configured in the /etc/rc.conf file: portmap_enable="YES" nfs_server_enable="YES" mountd_flags="-r" mountd runs automatically whenever the NFS server is enabled. On the client, make sure this option is present in /etc/rc.conf: nfs_client_enable="YES" The /etc/exports file specifies which filesystems NFS should export (sometimes referred to as share). Each line in /etc/exports specifies a filesystem to be exported and which machines have access to that filesystem. Along with what machines have access to that filesystem, access options may also be specified. There are many such options that can be used in this file but only a few will be mentioned here. You can easily discover other options by reading over the &man.exports.5; manual page. Here are a few example /etc/exports entries: NFS Examples of exporting filesystems The following examples give an idea of how to export filesystems, although the settings may be different depending on your environment and network configuration. For instance, to export the /cdrom directory to three example machines that have the same domain name as the server (hence the lack of a domain name for each) or have entries in your /etc/hosts file. The - flag makes the exported file system read-only. With this flag, the + flag makes the exported filesystem read-only. With this flag, the remote system will not be able to write any changes to the - exported file system. + exported filesystem. /cdrom -ro host1 host2 host3 The following line exports /home to three hosts by IP address. This is a useful setup if you have a private network without a DNS server configured. Optionally the /etc/hosts file could be configured for internal hostnames; please review &man.hosts.5; for more information. The flag allows the subdirectories to be mount points. In other words, it will not mount the subdirectories but permit the client to mount only the directories that are required or needed. /home -alldirs 10.0.0.2 10.0.0.3 10.0.0.4 The following line exports /a so that two clients from different domains may access the filesystem. The flag allows the root user on the remote system to write data on the exported filesystem as root. If the -maproot=root flag is not specified, then even if a user has root access on the remote system, they will not be able to modify files on the exported filesystem. /a -maproot=root host.example.com box.example.org In order for a client to access an exported filesystem, the client must have permission to do so. Make sure the client is listed in your /etc/exports file. In /etc/exports, each line represents the export information for one filesystem to one host. A remote host can only be specified once per filesystem, and may only have one default entry. For example, assume that /usr is a single filesystem. The following /etc/exports would be invalid: /usr/src client /usr/ports client One filesystem, /usr, has two lines specifying exports to the same host, client. The correct format for this situation is: /usr/src /usr/ports client The properties of one filesystem exported to a given host must all occur on one line. Lines without a client specified are treated as a single host. This limits how you can export filesystems, but for most people this is not an issue. The following is an example of a valid export list, where /usr and /exports are local filesystems: # Export src and ports to client01 and client02, but only # client01 has root privileges on it /usr/src /usr/ports -maproot=root client01 /usr/src /usr/ports client02 # The client machines have root and can mount anywhere # on /exports. Anyone in the world can mount /exports/obj read-only /exports -alldirs -maproot=root client01 client02 /exports/obj -ro You must restart mountd whenever you modify /etc/exports so the changes can take effect. This can be accomplished by sending the hangup signal to the mountd process: &prompt.root; kill -HUP `cat /var/run/mountd.pid` Alternatively, a reboot will make FreeBSD set everything up properly. A reboot is not necessary though. Executing the following commands as root should start everything up. On the NFS server: &prompt.root; portmap &prompt.root; nfsd -u -t -n 4 &prompt.root; mountd -r On the NFS client: &prompt.root; nfsiod -n 4 Now everything should be ready to actually mount a remote file system. In these examples the server's name will be server and the client's name will be client. If you only want to - temporarily mount a remote file system or would rather test the + temporarily mount a remote filesystem or would rather test the configuration, just execute a command like this as root on the client: NFS mounting filesystems &prompt.root; mount server:/home /mnt This will mount the /home directory on the server at /mnt on the client. If everything is set up correctly you should be able to enter /mnt on the client and see all the files that are on the server. If you want to automatically mount a remote filesystem each time the computer boots, add the filesystem to the /etc/fstab file. Here is an example: server:/home /mnt nfs rw 0 0 The &man.fstab.5; manual page lists all the available options. Practical Uses NFS has many practical uses. Some of the more common ones are listed below: NFS uses Set several machines to share a CDROM or other media among them. This is cheaper and often a more convenient method to install software on multiple machines. On large networks, it might be more convenient to configure a central NFS server in which to store all the user home directories. These home directories can then be exported to the network so that users would always have the same home directory, regardless of which workstation they log in to. You can use an exported CDROM to install software on multiple machines. Several machines could have a common /usr/ports/distfiles directory. That way, when you need to install a port on several machines, you can quickly access the source without downloading it on each machine. Wylie Stilwell Contributed by Chern Lee Rewritten by amd amd automatic mounter daemon &man.amd.8; (the automatic mounter daemon) automatically mounts a remote filesystem whenever a file or directory within that filesystem is accessed. Filesystems that are inactive for a period of time will also be automatically unmounted by amd. Using amd provides a simple alternative to permanent mounts, as permanent mounts are usually listed in /etc/fstab. amd operates by attaching itself as an NFS server to the /host and /net directories. When a file is accessed within one of these directories, amd looks up the corresponding remote mount and automatically mounts it. /net is used to mount an exported filesystem from an IP address, while /host is used to mount an export from a remote hostname. An access to a file within /host/foobar/usr would tell amd to attempt to mount the /usr export on the host foobar. Mounting an Export with <application>amd</application> &prompt.user; showmount -e foobar Exports list on foobar: /usr 10.10.10.0 /a 10.10.10.0 &prompt.user; cd /host/foobar/usr As seen in the example, the showmount shows /usr as an export. When changing directories to /host/foobar/usr, amd attempts to resolve the hostname foobar and automatically mount the desired export. amd can be started through the rc.conf system by placing the following lines in /etc/rc.conf: amd_enable="YES" Additionally, custom flags can be passed to amd from the amd_flags option. By default, amd_flags is set to: amd_flags="-a /.amd_mnt -l syslog /host /etc/amd.map /net /etc/amd.map" The /etc/amd.map file defines the default options that exports are mounted with. The /etc/amd.conf file defines some of the more advanced features of amd. Consult the &man.amd.8; and &man.amd.conf.5; man pages for more information. John Lind Contributed by Problems Integrating with Other Systems Certain Ethernet adapters for ISA PC systems have limitations which can lead to serious network problems, particularly with NFS. This difficulty is not specific to FreeBSD, but FreeBSD systems are affected by it. The problem nearly always occurs when (FreeBSD) PC systems are networked with high-performance workstations, such as those made by Silicon Graphics, Inc., and Sun Microsystems, Inc. The NFS mount will work fine, and some operations may succeed, but suddenly the server will seem to become unresponsive to the client, even though requests to and from other systems continue to be processed. This happens to the client system, whether the client is the FreeBSD system or the workstation. On many systems, there is no way to shut down the client gracefully once this problem has manifested itself. The only solution is often to reset the client, because the NFS situation cannot be resolved. Though the correct solution is to get a higher performance and capacity Ethernet adapter for the FreeBSD system, there is a simple workaround that will allow satisfactory operation. If the FreeBSD system is the server, include the option on the mount from the client. If the FreeBSD system is the client, then mount the - NFS file system with the option . These + NFS filesystem with the option . These options may be specified using the fourth field of the fstab entry on the client for automatic mounts, or by using the parameter of the mount command for manual mounts. It should be noted that there is a different problem, sometimes mistaken for this one, when the NFS servers and clients are on different networks. If that is the case, make certain that your routers are routing the necessary UDP information, or you will not get anywhere, no matter what else you are doing. In the following examples, fastws is the host (interface) name of a high-performance workstation, and freebox is the host (interface) name of a FreeBSD system with a lower-performance Ethernet adapter. Also, /sharedfs will be the exported NFS filesystem (see &man.exports.5;), and /project will be the mount point on the - client for the exported file system. In all cases, note that + client for the exported filesystem. In all cases, note that additional options, such as or and may be desirable in your application. Examples for the FreeBSD system (freebox) as the client in /etc/fstab on freebox: fastws:/sharedfs /project nfs rw,-r=1024 0 0 As a manual mount command on freebox: &prompt.root; mount -t nfs -o -r=1024 fastws:/sharedfs /project Examples for the FreeBSD system as the server in /etc/fstab on fastws: freebox:/sharedfs /project nfs rw,-w=1024 0 0 As a manual mount command on fastws: &prompt.root; mount -t nfs -o -w=1024 freebox:/sharedfs /project Nearly any 16-bit Ethernet adapter will allow operation without the above restrictions on the read or write size. For anyone who cares, here is what happens when the failure occurs, which also explains why it is unrecoverable. NFS typically works with a block size of 8k (though it may do fragments of smaller sizes). Since the maximum Ethernet packet is around 1500 bytes, the NFS block gets split into multiple Ethernet packets, even though it is still a single unit to the upper-level code, and must be received, assembled, and acknowledged as a unit. The high-performance workstations can pump out the packets which comprise the NFS unit one right after the other, just as close together as the standard allows. On the smaller, lower capacity cards, the later packets overrun the earlier packets of the same unit before they can be transferred to the host and the unit as a whole cannot be reconstructed or acknowledged. As a result, the workstation will time out and try again, but it will try again with the entire 8K unit, and the process will be repeated, ad infinitum. By keeping the unit size below the Ethernet packet size limitation, we ensure that any complete Ethernet packet received can be acknowledged individually, avoiding the deadlock situation. Overruns may still occur when a high-performance workstations is slamming data out to a PC system, but with the better cards, such overruns are not guaranteed on NFS units. When an overrun occurs, the units affected will be retransmitted, and there will be a fair chance that they will be received, assembled, and acknowledged. Jean-François Dockès Updated by Diskless Operation diskless workstation diskless operation A FreeBSD machine can boot over the network and operate without a - local disk, using file systems mounted from an NFS server. No system + local disk, using filesystems mounted from an NFS server. No system modification is necessary, beyond standard configuration files. Such a system is easy to set up because all the necessary elements are readily available: There are at least two possible methods to load the kernel over the network: PXE: Intel's Preboot Execution Environment system is a form of smart boot ROM built into some networking cards or motherboards. See &man.pxeboot.8; for more details. The etherboot port (net/etherboot) produces ROM-able code to boot kernels over the network. The code can be either burnt into a boot PROM on a network card, or loaded from a local floppy (or hard) disk drive, or from a running MS-DOS system. Many network cards are supported. A sample script (/usr/share/examples/diskless/clone_root) eases the creation and maintenance of the workstation's root filesystem on the server. The script will probably require a little customization but it will get you started very quickly. Standard system startup files exist in /etc to detect and support a diskless system startup. Swapping, if needed, can be done either to an NFS file or to a local disk. There are many ways to set up diskless workstations. Many elements are involved, and most can be customized to suit local taste. The following will describe the setup of a complete system, emphasizing simplicity and compatibility with the standard FreeBSD startup scripts. The system described has the following characteristics: The diskless workstations use a shared read-only root filesystem, and a shared read-only /usr. - The root file system is a copy of a + The root filesystem is a copy of a standard FreeBSD root (typically the server's), with some configuration files overridden by ones specific to diskless operation or, possibly, to the workstation they belong to. The parts of the root which have to be writable are overlaid with &man.mfs.8; filesystems. Any changes will be lost when the system reboots. The kernel is loaded by etherboot , using DHCP (or BOOTP) and TFTP. As described, this system is insecure. It should live in a protected area of a network, and be untrusted by other hosts. Setup Instructions Configuring DHCP/BOOTP There are two protocols that are commonly used to boot a workstation that retrieves its configuration over the network: BOOTP and DHCP. They are used at several points in the workstation bootstrap: etherboot uses DHCP (by default) or BOOTP (needs a configuration option) to find the kernel. (PXE uses DHCP). The kernel uses BOOTP to locate the NFS root. It is possible to configure a system to use only BOOTP. The &man.bootpd.8; server program is included in the base FreeBSD system. However, DHCP has a number of advantages over BOOTP (nicer configuration files, possibility of using PXE, plus many others not directly related to diskless operation), and we shall describe both a pure BOOTP, and a BOOTP+DHCP configuration, with an emphasis on the latter, which will use the ISC DHCP software package. Configuration Using ISC DHCP The isc-dhcp server can answer both BOOTP and DHCP requests. As of release 4.4, isc-dhcp 3.0 is not part of the base system. You will first need to install the net/isc-dhcp3 port or the corresponding package. Please refer to for general information about ports and packages. Once isc-dhcp is installed, it needs a configuration file to run, (normally named /usr/local/etc/dhcpd.conf). Here follows a commented example: default-lease-time 600; max-lease-time 7200; authoritative; option domain-name "example.com"; option domain-name-servers 192.168.4.1; option routers 192.168.4.1; subnet 192.168.4.0 netmask 255.255.255.0 { use-host-decl-names on; option subnet-mask 255.255.255.0; option broadcast-address 192.168.4.255; host margaux { hardware ethernet 01:23:45:67:89:ab; fixed-address margaux.example.com; next-server 192.168.4.4; filename "/tftpboot/kernel.diskless"; option root-path "192.168.4.4:/data/misc/diskless"; } } This option tells dhcpd to send the value in the host declarations as the hostname for the diskless host. An alternate way would be to add an option host-name margaux inside the host declarations. The next-server directive designates the TFTP server (the default is to use the same host as the DHCP server). The filename directive defines the file that etherboot will load as a kernel. PXE appears to prefer a relative file name, and it loads pxeboot, not the kernel (option filename "pxeboot"). The root-path option defines the path to the root filesystem, in usual NFS notation. Configuration Using BOOTP Here follows an equivalent bootpd configuration. This would be found in /etc/bootptab. Please note that etherboot must be compiled with the non-default option NO_DHCP_SUPPORT in order to use BOOTP, and that PXE needs DHCP. The only obvious advantage of bootpd is that it exists in the base system. .def100:\ :hn:ht=1:sa=192.168.4.4:vm=rfc1048:\ :sm=255.255.255.0:\ :ds=192.168.4.1:\ :gw=192.168.4.1:\ :hd="/tftpboot":\ :bf="/kernel.diskless":\ :rp="192.168.4.4:/data/misc/diskless": margaux:ha=0123456789ab:tc=.def100 Preparing a Boot Program with <application>Etherboot</application> Etherboot's Web site contains extensive documentation mainly intended for Linux systems, but nonetheless containing useful information. The following will just outline how you would use etherboot on a FreeBSD system. You must first install - and possibly compile - the etherboot package. The etherboot port can normally be found in /usr/ports/net/etherboot. If the ports tree is installed on your system, just typing make in this directory should take care of everything. Else refer to for information about ports and packages. For our setup, we shall use a boot floppy. For other methods (PROM, or dos program), please refer to the etherboot documentation. To make a boot floppy, insert a floppy in the drive on the machine where you installed etherboot, then change your current directory to the src directory in the etherboot tree and type: &prompt.root; gmake bin32/devicetype.fd0 devicetype depends on the type of the Ethernet card in the diskless workstation. Refer to the NIC file in the same directory to determine the right devicetype. Configuring the TFTP and NFS Servers You need to enable tftpd on the TFTP server: Create a directory from which tftpd will serve the files, i.e.: /tftpboot Add this line to your /etc/inetd.conf: tftp dgram udp wait nobody /usr/libexec/tftpd tftpd /tftpboot It appears that at least some PXE versions want the TCP version of TFTP. In this case, add a second line, replacing dgram udp with stream tcp. Tell inetd to reread its configuration file: &prompt.root; kill -HUP `cat /var/run/inetd.pid` You can place the tftpboot directory anywhere on the server. Make sure that the location is set in both inetd.conf and dhcpd.conf. You also need to enable NFS service and export the appropriate filesystem on the NFS server. Add this to /etc/rc.conf: nfs_server_enable="YES" Export the filesystem where the diskless root directory is located by adding the following to /etc/exports (adjust the volume mount point and workstation name!): /data/misc -alldirs -ro margaux Tell mountd to reread its configuration file. If you actually needed to configure NFS service at step 1, you probably want to reboot instead. &prompt.root; kill -HUP `cat /var/run/mountd.pid` Building a Diskless Kernel Create a kernel configuration file for the diskless client with the following options (in addition to the usual ones): options BOOTP # Use BOOTP to obtain IP address/hostname options BOOTP_NFSROOT # NFS mount root filesystem using BOOTP info options BOOTP_COMPAT # Workaround for broken bootp daemons. You may also want to use BOOTP_NFSV3 and BOOTP_WIRED_TO (refer to LINT). Build the kernel (See ), and copy it to the tftp directory, under the name listed in dhcpd.conf. Preparing the root Filesystem You need to create a root filesystem for the diskless workstations, in the location listed as root-path in dhcpd.conf. The easiest way to do this is to use the /usr/share/examples/diskless/clone_root shell script. This script needs customization, at least to adjust the place where the filesystem will be created (the DEST variable). Refer to the comments at the top of the script for instructions. They explain how the base filesystem is built, and how files may be selectively overridden by versions specific to diskless operation, to a subnetwork, or to an individual workstation. They also give examples for the diskless /etc/fstab and /etc/rc.conf. The README files in /usr/share/examples/diskless contain a lot of interesting background information, but, together with the other examples in the diskless directory, they actually document a configuration method which is distinct from the one used by clone_root and /etc/rc.diskless[12], which is a little confusing. Use them for reference only, except if you prefer the method that they describe, in which case you will need customized rc scripts. As of FreeBSD version 4.4-RELEASE, there is a small incompatibility between the clone_root script and the /etc/rc.diskless1 script. Please refer to PR conf/31200 for the small adjustment needed in clone_root. Also see PR conf/29870 about a small adjustment needed in /etc/rc.diskless2. Configuring Swap If needed, a swap file located on the server can be accessed via NFS. The exact bootptab or dhcpd.conf options are not clearly documented at this time. The following configuration suggestions have been reported to work in some installations using isc-dhcp 3.0rc11. Add the following lines to dhcpd.conf: # Global section option swap-path code 128 = string; option swap-size code 129 = integer 32; host margaux { ... # Standard lines, see above option swap-path "192.168.4.4:/netswapvolume/netswap"; option swap-size 64000; } The idea is that, at least for a FreeBSD client, DHCP/BOOTP option code 128 is the path to the NFS swap file, and option code 129 is the swap size in kilobytes. Older versions of dhcpd allowed a syntax of option option-128 "..., which does not seem to work any more. /etc/bootptab would use the following syntax instead: T128="192.168.4.4:/netswapvolume/netswap":T129=64000 On the NFS swap file server, create the swap file(s) &prompt.root; mkdir /netswapvolume/netswap &prompt.root; cd /netswapvolume/netswap &prompt.root; dd if=/dev/zero bs=1024 count=64000 of=swap.192.168.4.6 &prompt.root; chmod 0600 swap.192.168.4.6 192.168.4.6 is the IP address for the diskless client. On the NFS swap file server, add the following line to /etc/exports: /netswapvolume -maproot=0:10 -alldirs margaux Then tell mountd to reread the exports file, as above. Miscellaneous Issues Running with a read-only <filename>/usr</filename>If the diskless workstation is configured to run X, you will have to adjust the xdm configuration file, which puts the error log on /usr by default. Using a non-FreeBSD Server When the server for the root filesystem is not running FreeBSD, - you will have to create the root file system on a + you will have to create the root filesystem on a FreeBSD machine, then copy it to its destination, using tar or cpio. In this situation, there are sometimes problems with the special files in /dev, due to differing major/minor integer sizes. A solution to this problem is to export a directory from the non-FreeBSD server, mount this directory onto a FreeBSD machine, and run MAKEDEV on the FreeBSD machine to create the correct device entries. ISDN A good resource for information on ISDN technology and hardware is Dan Kegel's ISDN Page. A quick simple road map to ISDN follows: If you live in Europe you might want to investigate the ISDN card section. If you are planning to use ISDN primarily to connect to the Internet with an Internet Provider on a dial-up non-dedicated basis, you might look into Terminal Adapters. This will give you the most flexibility, with the fewest problems, if you change providers. If you are connecting two LANs together, or connecting to the Internet with a dedicated ISDN connection, you might consider the stand alone router/bridge option. Cost is a significant factor in determining what solution you will choose. The following options are listed from least expensive to most expensive. Hellmuth Michaelis Contributed by ISDN Cards ISDN cards FreeBSD's ISDN implementation supports only the DSS1/Q.931 (or Euro-ISDN) standard using passive cards. Starting with FreeBSD 4.4, some active cards are supported where the firmware also supports other signaling protocols; this also includes the first supported Primary Rate (PRI) ISDN card. Isdn4bsd allows you to connect to other ISDN routers using either IP over raw HDLC or by using synchronous PPP: either by using kernel PPP with isppp, a modified sppp driver, or by using userland &man.ppp.8;. By using userland &man.ppp.8;, channel bonding of two or more ISDN B-channels is possible. A telephone answering machine application is also available as well as many utilities such as a software 300 Baud modem. Some growing number of PC ISDN cards are supported under FreeBSD and the reports show that it is successfully used all over Europe and in many other parts of the world. The passive ISDN cards supported are mostly the ones with the Infineon (formerly Siemens) ISAC/HSCX/IPAC ISDN chipsets, but also ISDN cards with chips from Cologne Chip (ISA bus only), PCI cards with Winbond W6692 chips, some cards with the Tiger300/320/ISAC chipset combinations and some vendor specific chipset based cards such as the AVM Fritz!Card PCI V.1.0 and the AVM Fritz!Card PnP. Currently the active supported ISDN cards are the AVM B1 (ISA and PCI) BRI cards and the AVM T1 PCI PRI cards. For documentation on isdn4bsd, have a look at /usr/share/examples/isdn/ directory on your FreeBSD system or at the homepage of isdn4bsd which also has pointers to hints, erratas and much more documentation such as the isdn4bsd handbook. In case you are interested in adding support for a different ISDN protocol, a currently unsupported ISDN PC card or otherwise enhancing isdn4bsd, please get in touch with &a.hm;. For questions regarding the installation, configuration and troubleshooting isdn4bsd, a majordomo maintained mailing list is available. To join, send mail to &a.majordomo; and specify: subscribe freebsd-isdn in the body of your message. ISDN Terminal Adapters Terminal adapters(TA), are to ISDN what modems are to regular phone lines. modem Most TA's use the standard hayes modem AT command set, and can be used as a drop in replacement for a modem. A TA will operate basically the same as a modem except connection and throughput speeds will be much faster than your old modem. You will need to configure PPP exactly the same as for a modem setup. Make sure you set your serial speed as high as possible. PPP The main advantage of using a TA to connect to an Internet Provider is that you can do Dynamic PPP. As IP address space becomes more and more scarce, most providers are not willing to provide you with a static IP anymore. Most stand-alone routers are not able to accommodate dynamic IP allocation. TA's completely rely on the PPP daemon that you are running for their features and stability of connection. This allows you to upgrade easily from using a modem to ISDN on a FreeBSD machine, if you already have PPP setup. However, at the same time any problems you experienced with the PPP program and are going to persist. If you want maximum stability, use the kernel PPP option, not the user-land iijPPP. The following TA's are known to work with FreeBSD. Motorola BitSurfer and Bitsurfer Pro Adtran Most other TA's will probably work as well, TA vendors try to make sure their product can accept most of the standard modem AT command set. The real problem with external TA's is that, like modems, you need a good serial card in your computer. You should read the FreeBSD Serial Hardware tutorial for a detailed understanding of serial devices, and the differences between asynchronous and synchronous serial ports. A TA running off a standard PC serial port (asynchronous) limits you to 115.2Kbs, even though you have a 128Kbs connection. To fully utilize the 128Kbs that ISDN is capable of, you must move the TA to a synchronous serial card. Do not be fooled into buying an internal TA and thinking you have avoided the synchronous/asynchronous issue. Internal TA's simply have a standard PC serial port chip built into them. All this will do is save you having to buy another serial cable and find another empty electrical socket. A synchronous card with a TA is at least as fast as a stand-alone router, and with a simple 386 FreeBSD box driving it, probably more flexible. The choice of sync/TA v.s. stand-alone router is largely a religious issue. There has been some discussion of this in the mailing lists. I suggest you search the archives for the complete discussion. Stand-alone ISDN Bridges/Routers ISDN stand-alone bridges/routers ISDN bridges or routers are not at all specific to FreeBSD or any other operating system. For a more complete description of routing and bridging technology, please refer to a Networking reference book. In the context of this page, the terms router and bridge will be used interchangeably. As the cost of low end ISDN routers/bridges comes down, it will likely become a more and more popular choice. An ISDN router is a small box that plugs directly into your local Ethernet network, and manages its own connection to the other bridge/router. It has built in software to communicate via PPP and other popular protocols. A router will allow you much faster throughput than a standard TA, since it will be using a full synchronous ISDN connection. The main problem with ISDN routers and bridges is that interoperability between manufacturers can still be a problem. If you are planning to connect to an Internet provider, you should discuss your needs with them. If you are planning to connect two LAN segments together, such as your home LAN to the office LAN, this is the simplest lowest maintenance solution. Since you are buying the equipment for both sides of the connection you can be assured that the link will work. For example to connect a home computer or branch office network to a head office network the following setup could be used. Branch Office or Home Network 10 base 2 Network uses a bus based topology with 10 base 2 Ethernet ("thinnet"). Connect router to network cable with AUI/10BT transceiver, if necessary. ---Sun workstation | ---FreeBSD box | ---Windows 95 (Do not admit to owning it) | Stand-alone router | ISDN BRI line 10 Base 2 Ethernet If your home/branch office is only one computer you can use a twisted pair crossover cable to connect to the stand-alone router directly. Head Office or Other LAN 10 base T Network uses a star topology with 10 base T Ethernet ("Twisted Pair"). -------Novell Server | H | | ---Sun | | | U ---FreeBSD | | | ---Windows 95 | B | |___---Stand-alone router | ISDN BRI line ISDN Network Diagram One large advantage of most routers/bridges is that they allow you to have 2 separate independent PPP connections to 2 separate sites at the same time. This is not supported on most TA's, except for specific (usually expensive) models that have two serial ports. Do not confuse this with channel bonding, MPP, etc. This can be a very useful feature if, for example, you have an dedicated ISDN connection at your office and would like to tap into it, but do not want to get another ISDN line at work. A router at the office location can manage a dedicated B channel connection (64Kbps) to the Internet and use the other B channel for a separate data connection. The second B channel can be used for dial-in, dial-out or dynamically bonding (MPP, etc.) with the first B channel for more bandwidth. IPX/SPX An Ethernet bridge will also allow you to transmit more than just IP traffic. You can also send IPX/SPX or whatever other protocols you use. Bill Swingle Written by Eric Ogren Enhanced by Udo Erdelhoff NIS/YP What Is It? NIS Solaris HP-UX AIX Linux NetBSD OpenBSD NIS, which stands for Network Information Services, was developed by Sun Microsystems to centralize administration of Unix (originally SunOS) systems. It has now essentially become an industry standard; all major Unix systems (Solaris, HP-UX, AIX, Linux, NetBSD, OpenBSD, FreeBSD, etc) support NIS. yellow pagesNIS NIS was formerly known as Yellow Pages, but because of trademark issues, Sun changed the name. The old term (and yp) is still often seen and used. NIS domains It is a RPC-based client/server system that allows a group of machines within an NIS domain to share a common set of configuration files. This permits a system administrator to set up NIS client systems with only minimal configuration data and add, remove or modify configuration data from a single location. Windows NT It is similar to Windows NT's domain system; although the internal implementation of the two are not at all similar, the basic functionality can be compared. Terms/Processes You Should Know There are several terms and several important user processes that you will come across when attempting to implement NIS on FreeBSD, whether you are trying to create an NIS server or act as an NIS client: portmap Term Description NIS domainname An NIS master server and all of its clients (including its slave servers) have a NIS domainname. Similar to an NT domain name, the NIS domainname does not have anything to do with DNS. portmap Must be running in order to enable RPC (Remote Procedure Call, a network protocol used by NIS). If portmap is not running, it will be impossible to run an NIS server, or to act as an NIS client. ypbind binds an NIS client to its NIS server. It will take the NIS domainname from the system, and using RPC, connect to the server. ypbind is the core of client-server communication in an NIS environment; if ypbind dies on a client machine, it will not be able to access the NIS server. ypserv Should only be running on NIS servers, is the NIS server process itself. If &man.ypserv.8; dies, then the server will no longer be able to respond to NIS requests (hopefully, there is a slave server to take over for it). There are some implementations of NIS (but not the FreeBSD one), that do not try to reconnect to another server if the server it used before dies. Often, the only thing that helps in this case is to restart the server process (or even the whole server) or the ypbind process on the client. rpc.yppasswdd Another process that should only be running on NIS master servers, is a daemon that will allow NIS clients to change their NIS passwords. If this daemon is not running, users will have to login to the NIS master server and change their passwords there. How Does It Work? There are three types of hosts in an NIS environment: master servers, slave servers, and clients. Servers act as a central repository for host configuration information. Master servers hold the authoritative copy of this information, while slave servers mirror this information for redundancy. Clients rely on the servers to provide this information to them. Information in many files can be shared in this manner. The master.passwd, group, and hosts files are commonly shared via NIS. Whenever a process on a client needs information that would normally be found in these files locally, it makes a query to the NIS server that it is bound to instead. Machine Types NIS master server A NIS master server. This server, analogous to a Windows NT primary domain controller, maintains the files used by all of the NIS clients. The passwd, group, and other various files used by the NIS clients live on the master server. It is possible for one machine to be an NIS master server for more than one NIS domain. However, this will not be covered in this introduction, which assumes a relatively small-scale NIS environment. NIS slave server NIS slave servers. Similar to NT's backup domain controllers, NIS slave servers maintain copies of the NIS master's data files. NIS slave servers provide the redundancy, which is needed in important environments. They also help to balance the load of the master server: NIS Clients always attach to the NIS server whose response they get first, and this includes slave-server-replies. NIS client NIS clients. NIS clients, like most NT workstations, authenticate against the NIS server (or the NT domain controller in the NT Workstation case) to log on. Using NIS/YP This section will deal with setting up a sample NIS environment. This section assumes that you are running FreeBSD 3.3 or later. The instructions given here will probably work for any version of FreeBSD greater than 3.0, but there are no guarantees that this is true. Planning Let us assume that you are the administrator of a small university lab. This lab, which consists of 15 FreeBSD machines, currently has no centralized point of administration; each machine has its own /etc/passwd and /etc/master.passwd. These files are kept in sync with each other only through manual intervention; currently, when you add a user to the lab, you must run adduser on all 15 machines. Clearly, this has to change, so you have decided to convert the lab to use NIS, using two of the machines as servers. Therefore, the configuration of the lab now looks something like: Machine name IP address Machine role ellington 10.0.0.2 NIS master coltrane 10.0.0.3 NIS slave basie 10.0.0.4 Faculty workstation bird 10.0.0.5 Client machine cli[1-11] 10.0.0.[6-17] Other client machines If you are setting up a NIS scheme for the first time, it is a good idea to think through how you want to go about it. No matter what the size of your network, there are a few decisions that need to be made. Choosing a NIS Domain Name NIS domainname This might not be the domainname that you are used to. It is more accurately called the NIS domainname. When a client broadcasts its requests for info, it includes the name of the NIS domain that it is part of. This is how multiple servers on one network can tell which server should answer which request. Think of the NIS domainname as the name for a group of hosts that are related in some way. Some organizations choose to use their Internet domainname for their NIS domainname. This is not recommended as it can cause confusion when trying to debug network problems. The NIS domainname should be unique within your network and it is helpful if it describes the group of machines it represents. For example, the Art department at Acme Inc. might be in the "acme-art" NIS domain. For this example, assume you have chosen the name test-domain. SunOS However, some operating systems (notably SunOS) use their NIS domain name as their Internet domain name. If one or more machines on your network have this restriction, you must use the Internet domain name as your NIS domain name. Physical Server Requirements There are several things to keep in mind when choosing a machine to use as a NIS server. One of the unfortunate things about NIS is the level of dependency the clients have on the server. If a client cannot contact the server for its NIS domain, very often the machine becomes unusable. The lack of user and group information causes most systems to temporarily freeze up. With this in mind you should make sure to choose a machine that will not be prone to being rebooted regularly, or one that might be used for development. The NIS server should ideally be a stand alone machine whose sole purpose in life is to be an NIS server. If you have a network that is not very heavily used, it is acceptable to put the NIS server on a machine running other services, just keep in mind that if the NIS server becomes unavailable, it will affect all of your NIS clients adversely. NIS Servers The canonical copies of all NIS information are stored on a single machine called the NIS master server. The databases used to store the information are called NIS maps. In FreeBSD, these maps are stored in /var/yp/[domainname] where [domainname] is the name of the NIS domain being served. A single NIS server can support several domains at once, therefore it is possible to have several such directories, one for each supported domain. Each domain will have its own independent set of maps. NIS master and slave servers handle all NIS requests with the ypserv daemon. ypserv is responsible for receiving incoming requests from NIS clients, translating the requested domain and map name to a path to the corresponding database file and transmitting data from the database back to the client. Setting Up a NIS Master Server NIS server configuration Setting up a master NIS server can be relatively straight forward, depending on your needs. FreeBSD comes with support for NIS out-of-the-box. All you need is to add the following lines to /etc/rc.conf, and FreeBSD will do the rest for you. nisdomainname="test-domain" This line will set the NIS domainname to test-domain upon network setup (e.g. after reboot). nis_server_enable="YES" This will tell FreeBSD to start up the NIS server processes when the networking is next brought up. nis_yppasswdd_enable="YES" This will enable the rpc.yppasswdd daemon which, as mentioned above, will allow users to change their NIS password from a client machine. Depending on your NIS setup, you may need to add further entries. See the section about NIS servers that are also NIS clients, below, for details. Now, all you have to do is to run the command /etc/netstart as superuser. It will set up everything for you, using the values you defined in /etc/rc.conf. Initializing the NIS Maps NIS maps The NIS maps are database files, that are kept in the /var/yp directory. They are generated from configuration files in the /etc directory of the NIS master, with one exception: the /etc/master.passwd file. This is for a good reason; you do not want to propagate passwords to your root and other administrative accounts to all the servers in the NIS domain. Therefore, before we initialize the NIS maps, you should: &prompt.root; cp /etc/master.passwd /var/yp/master.passwd &prompt.root; cd /var/yp &prompt.root; vi master.passwd You should remove all entries regarding system accounts (bin, tty, kmem, games, etc), as well as any accounts that you do not want to be propagated to the NIS clients (for example root and any other UID 0 (superuser) accounts). Make sure the /var/yp/master.passwd is neither group nor world readable (mode 600)! Use the chmod command, if appropriate. Tru64 Unix When you have finished, it is time to initialize the NIS maps! FreeBSD includes a script named ypinit to do this for you (see its manual page for more information). Note that this script is available on most Unix Operating Systems, but not on all. On Digital Unix/Compaq Tru64 Unix it is called ypsetup. Because we are generating maps for an NIS master, we are going to pass the option to ypinit. To generate the NIS maps, assuming you already performed the steps above, run: ellington&prompt.root; ypinit -m test-domain Server Type: MASTER Domain: test-domain Creating an YP server will require that you answer a few questions. Questions will all be asked at the beginning of the procedure. Do you want this procedure to quit on non-fatal errors? [y/n: n] n Ok, please remember to go back and redo manually whatever fails. If you don't, something might not work. At this point, we have to construct a list of this domains YP servers. rod.darktech.org is already known as master server. Please continue to add any slave servers, one per line. When you are done with the list, type a <control D>. master server : ellington next host to add: coltrane next host to add: ^D The current list of NIS servers looks like this: ellington coltrane Is this correct? [y/n: y] y [..output from map generation..] NIS Map update completed. ellington has been setup as an YP master server without any errors. ypinit should have created /var/yp/Makefile from /var/yp/Makefile.dist. When created, this file assumes that you are operating in a single server NIS environment with only FreeBSD machines. Since test-domain has a slave server as well, you must edit /var/yp/Makefile: ellington&prompt.root; vi /var/yp/Makefile You should comment out the line that says `NOPUSH = "True"' (if it is not commented out already). Setting up a NIS Slave Server NIS configuring a slave server Setting up an NIS slave server is even more simple than setting up the master. Log on to the slave server and edit the file /etc/rc.conf as you did before. The only difference is that we now must use the option when running ypinit. The option requires the name of the NIS master be passed to it as well, so our command line looks like: coltrane&prompt.root; ypinit -s ellington test-domain Server Type: SLAVE Domain: test-domain Master: ellington Creating an YP server will require that you answer a few questions. Questions will all be asked at the beginning of the procedure. Do you want this procedure to quit on non-fatal errors? [y/n: n] n Ok, please remember to go back and redo manually whatever fails. If you don't, something might not work. There will be no further questions. The remainder of the procedure should take a few minutes, to copy the databases from ellington. Transferring netgroup... ypxfr: Exiting: Map successfully transferred Transferring netgroup.byuser... ypxfr: Exiting: Map successfully transferred Transferring netgroup.byhost... ypxfr: Exiting: Map successfully transferred Transferring master.passwd.byuid... ypxfr: Exiting: Map successfully transferred Transferring passwd.byuid... ypxfr: Exiting: Map successfully transferred Transferring passwd.byname... ypxfr: Exiting: Map successfully transferred Transferring group.bygid... ypxfr: Exiting: Map successfully transferred Transferring group.byname... ypxfr: Exiting: Map successfully transferred Transferring services.byname... ypxfr: Exiting: Map successfully transferred Transferring rpc.bynumber... ypxfr: Exiting: Map successfully transferred Transferring rpc.byname... ypxfr: Exiting: Map successfully transferred Transferring protocols.byname... ypxfr: Exiting: Map successfully transferred Transferring master.passwd.byname... ypxfr: Exiting: Map successfully transferred Transferring networks.byname... ypxfr: Exiting: Map successfully transferred Transferring networks.byaddr... ypxfr: Exiting: Map successfully transferred Transferring netid.byname... ypxfr: Exiting: Map successfully transferred Transferring hosts.byaddr... ypxfr: Exiting: Map successfully transferred Transferring protocols.bynumber... ypxfr: Exiting: Map successfully transferred Transferring ypservers... ypxfr: Exiting: Map successfully transferred Transferring hosts.byname... ypxfr: Exiting: Map successfully transferred coltrane has been setup as an YP slave server without any errors. Don't forget to update map ypservers on ellington. You should now have a directory called /var/yp/test-domain. Copies of the NIS master server's maps should be in this directory. You will need to make sure that these stay updated. The following /etc/crontab entries on your slave servers should do the job: 20 * * * * root /usr/libexec/ypxfr passwd.byname 21 * * * * root /usr/libexec/ypxfr passwd.byuid These two lines force the slave to sync its maps with the maps on the master server. Although these entries are not mandatory, since the master server attempts to ensure any changes to its NIS maps are communicated to its slaves and because password information is vital to systems depending on the server, it is a good idea to force the updates. This is more important on busy networks where map updates might not always complete. Now, run the command /etc/netstart on the slave server as well, which again starts the NIS server. NIS Clients An NIS client establishes what is called a binding to a particular NIS server using the ypbind daemon. ypbind checks the system's default domain (as set by the domainname command), and begins broadcasting RPC requests on the local network. These requests specify the name of the domain for which ypbind is attempting to establish a binding. If a server that has been configured to serve the requested domain receives one of the broadcasts, it will respond to ypbind, which will record the server's address. If there are several servers available (a master and several slaves, for example), ypbind will use the address of the first one to respond. From that point on, the client system will direct all of its NIS requests to that server. ypbind will occasionally ping the server to make sure it is still up and running. If it fails to receive a reply to one of its pings within a reasonable amount of time, ypbind will mark the domain as unbound and begin broadcasting again in the hopes of locating another server. Setting Up an NIS Client NIS client configuration Setting up a FreeBSD machine to be a NIS client is fairly straightforward. Edit the file /etc/rc.conf and add the following lines in order to set the NIS domainname and start ypbind upon network startup: nisdomainname="test-domain" nis_client_enable="YES" To import all possible password entries from the NIS server, remove all user accounts from your /etc/master.passwd file and use vipw to add the following line to the end of the file: +::::::::: This line will afford anyone with a valid account in the NIS server's password maps an account. There are many ways to configure your NIS client by changing this line. See the netgroups section below for more information. For more detailed reading see O'Reilly's book on Managing NFS and NIS. You should keep at least one local account (i.e. not imported via NIS) in your /etc/master.passwd and this account should also be a member of the group wheel. If there is something wrong with NIS, this account can be used to log in remotely, become root, and fix things. To import all possible group entries from the NIS server, add this line to your /etc/group file: +:*:: After completing these steps, you should be able to run ypcat passwd and see the NIS server's passwd map. NIS Security In general, any remote user can issue an RPC to &man.ypserv.8; and retrieve the contents of your NIS maps, provided the remote user knows your domainname. To prevent such unauthorized transactions, &man.ypserv.8; supports a feature called securenets which can be used to restrict access to a given set of hosts. At startup, &man.ypserv.8; will attempt to load the securenets information from a file called /var/yp/securenets. This path varies depending on the path specified with the option. This file contains entries that consist of a network specification and a network mask separated by white space. Lines starting with # are considered to be comments. A sample securenets file might look like this: # allow connections from local host -- mandatory 127.0.0.1 255.255.255.255 # allow connections from any host # on the 192.168.128.0 network 192.168.128.0 255.255.255.0 # allow connections from any host # between 10.0.0.0 to 10.0.15.255 # this includes the machines in the testlab 10.0.0.0 255.255.240.0 If &man.ypserv.8; receives a request from an address that matches one of these rules, it will process the request normally. If the address fails to match a rule, the request will be ignored and a warning message will be logged. If the /var/yp/securenets file does not exist, ypserv will allow connections from any host. The ypserv program also has support for Wietse Venema's tcpwrapper package. This allows the administrator to use the tcpwrapper configuration files for access control instead of /var/yp/securenets. While both of these access control mechanisms provide some security, they, like the privileged port test, are vulnerable to IP spoofing attacks. All NIS-related traffic should be blocked at your firewall. Servers using /var/yp/securenets may fail to serve legitimate NIS clients with archaic TCP/IP implementations. Some of these implementations set all host bits to zero when doing broadcasts and/or fail to observe the subnet mask when calculating the broadcast address. While some of these problems can be fixed by changing the client configuration, other problems may force the retirement of the client systems in question or the abandonment of /var/yp/securenets. Using /var/yp/securenets on a server with such an archaic implementation of TCP/IP is a really bad idea and will lead to loss of NIS functionality for large parts of your network. tcpwrapper The use of the tcpwrapper package increases the latency of your NIS server. The additional delay may be long enough to cause timeouts in client programs, especially in busy networks or with slow NIS servers. If one or more of your client systems suffers from these symptoms, you should convert the client systems in question into NIS slave servers and force them to bind to themselves. Barring Some Users from Logging On In our lab, there is a machine basie that is supposed to be a faculty only workstation. We do not want to take this machine out of the NIS domain, yet the passwd file on the master NIS server contains accounts for both faculty and students. What can we do? There is a way to bar specific users from logging on to a machine, even if they are present in the NIS database. To do this, all you must do is add -username to the end of the /etc/master.passwd file on the client machine, where username is the username of the user you wish to bar from logging in. This should preferably be done using vipw, since vipw will sanity check your changes to /etc/master.passwd, as well as automatically rebuild the password database when you finish editing. For example, if we wanted to bar user bill from logging on to basie we would: basie&prompt.root; vipw [add -bill to the end, exit] vipw: rebuilding the database... vipw: done basie&prompt.root; cat /etc/master.passwd root:[password]:0:0::0:0:The super-user:/root:/bin/csh toor:[password]:0:0::0:0:The other super-user:/root:/bin/sh daemon:*:1:1::0:0:Owner of many system processes:/root:/sbin/nologin operator:*:2:5::0:0:System &:/:/sbin/nologin bin:*:3:7::0:0:Binaries Commands and Source,,,:/:/sbin/nologin tty:*:4:65533::0:0:Tty Sandbox:/:/sbin/nologin kmem:*:5:65533::0:0:KMem Sandbox:/:/sbin/nologin games:*:7:13::0:0:Games pseudo-user:/usr/games:/sbin/nologin news:*:8:8::0:0:News Subsystem:/:/sbin/nologin man:*:9:9::0:0:Mister Man Pages:/usr/share/man:/sbin/nologin bind:*:53:53::0:0:Bind Sandbox:/:/sbin/nologin uucp:*:66:66::0:0:UUCP pseudo-user:/var/spool/uucppublic:/usr/libexec/uucp/uucico xten:*:67:67::0:0:X-10 daemon:/usr/local/xten:/sbin/nologin pop:*:68:6::0:0:Post Office Owner:/nonexistent:/sbin/nologin nobody:*:65534:65534::0:0:Unprivileged user:/nonexistent:/sbin/nologin +::::::::: -bill basie&prompt.root; Udo Erdelhoff Contributed by Using Netgroups netgroups The method shown in the previous section works reasonably well if you need special rules for a very small number of users and/or machines. On larger networks, you will forget to bar some users from logging onto sensitive machines, or you may even have to modify each machine separately, thus losing the main benefit of NIS, centralized administration. The NIS developers' solution for this problem is called netgroups. Their purpose and semantics can be compared to the normal groups used by Unix file systems. The main differences are the lack of a numeric id and the ability to define a netgroup by including both user accounts and other netgroups. Netgroups were developed to handle large, complex networks with hundreds of users and machines. On one hand, this is a Good Thing if you are forced to deal with such a situation. On the other hand, this complexity makes it almost impossible to explain netgroups with really simple examples. The example used in the remainder of this section demonstrates this problem. Let us assume that your successful introduction of NIS in your laboratory caught your superiors' interest. Your next job is to extend your NIS domain to cover some of the other machines on campus. The two tables contain the names of the new users and new machines as well as brief descriptions of them. User Name(s) Description alpha, beta Normal employees of the IT department charlie, delta The new apprentices of the IT department echo, foxtrott, golf, ... Ordinary employees able, baker, ... The current interns Machine Name(s) Description war, death, famine, pollution Your most important servers. Only the IT employees are allowed to log onto these machines. pride, greed, envy, wrath, lust, sloth Less important servers. All members of the IT department are allowed to login onto these machines. one, two, three, four, ... Ordinary workstations. Only the real employees are allowed to use these machines. trashcan A very old machine without any critical data. Even the intern is allowed to use this box. If you tried to implement these restrictions by separately blocking each user, you would have to add one -user line to each system's passwd for each user who is not allowed to login onto that system. If you forget just one entry, you could be in trouble. It may be feasible to do this correctly during the initial setup, however you will eventually forget to add the lines for new users during day-to-day operations. After all, Murphy was an optimist. Handling this situation with netgroups offers several advantages. Each user need not be handled separately; you assign a user to one or more netgroups and allow or forbid logins for all members of the netgroup. If you add a new machine, you will only have to define login restrictions for netgroups. If a new user is added, you will only have to add the user to one or more netgroups. Those changes are independent of each other; no more for each combination of user and machine do... If your NIS setup is planned carefully, you will only have to modify exactly one central configuration file to grant or deny access to machines. The first step is the initialization of the NIS map netgroup. FreeBSD's &man.ypinit.8; does not create this map by default, but its NIS implementation will support it once it has been created. To create an empty map, simply type ellington&prompt.root; vi /var/yp/netgroup and start adding content. For our example, we need at least four netgroups: IT employees, IT apprentices, normal employees and interns. IT_EMP (,alpha,test-domain) (,beta,test-domain) IT_APP (,charlie,test-domain) (,delta,test-domain) USERS (,echo,test-domain) (,foxtrott,test-domain) \ (,golf,test-domain) INTERNS (,able,test-domain) (,baker,test-domain) IT_EMP, IT_APP etc. are the names of the netgroups. Each bracketed group adds one or more user accounts to it. The three fields inside a group are: The name of the host(s) where the following items are valid. If you do not specify a hostname, the entry is valid on all hosts. If you do specify a hostname, you will enter a realm of darkness, horror and utter confusion. The name of the account that belongs to this netgroup. The NIS domain for the account. You can import accounts from other NIS domains into your netgroup if you are one of the unlucky fellows with more than one NIS domain. Each of these fields can contain wildcards. See &man.netgroup.5; for details. netgroups Netgroup names longer than 8 characters should not be used, especially if you have machines running other operating systems within your NIS domain. The names are case sensitive; using capital letters for your netgroup names is an easy way to distinguish between user, machine and netgroup names. Some NIS clients (other than FreeBSD) cannot handle netgroups with a large number of entries. For example, some older versions of SunOS start to cause trouble if a netgroup contains more than 15 entries. You can circumvent this limit by creating several sub-netgroups with 15 users or less and a real netgroup that consists of the sub-netgroups: BIGGRP1 (,joe1,domain) (,joe2,domain) (,joe3,domain) [...] BIGGRP2 (,joe16,domain) (,joe17,domain) [...] BIGGRP3 (,joe31,domain) (,joe32,domain) BIGGROUP BIGGRP1 BIGGRP2 BIGGRP3 You can repeat this process if you need more than 225 users within a single netgroup. Activating and distributing your new NIS map is easy: ellington&prompt.root; cd /var/yp ellington&prompt.root; make This will generate the three NIS maps netgroup, netgroup.byhost and netgroup.byuser. Use &man.ypcat.1; to check if your new NIS maps are available: ellington&prompt.user; ypcat -k netgroup ellington&prompt.user; ypcat -k netgroup.byhost ellington&prompt.user; ypcat -k netgroup.byuser The output of the first command should resemble the contents of /var/yp/netgroup. The second command will not produce output if you have not specified host-specific netgroups. The third command can be used to get the list of netgroups for a user. The client setup is quite simple. To configure the server war, you only have to start &man.vipw.8; and replace the line +::::::::: with +@IT_EMP::::::::: Now, only the data for the users defined in the netgroup IT_EMP is imported into war's password database and only these users are allowed to login. Unfortunately, this limitation also applies to the ~ function of the shell and all routines converting between user names and numerical user ids. In other words, cd ~user will not work, ls -l will show the numerical id instead of the username and find . -user joe -print will fail with No such user. To fix this, you will have to import all user entries without allowing them to login onto your servers. This can be achieved by adding another line to /etc/master.passwd. This line should contain: +:::::::::/sbin/nologin, meaning Import all entries but replace the shell with /sbin/nologin in the imported entries. You can replace any field in the passwd entry by placing a default value in your /etc/master.passwd. Make sure that the line +:::::::::/sbin/nologin is placed after +@IT_EMP:::::::::. Otherwise, all user accounts imported from NIS will have /sbin/nologin as their login shell. After this change, you will only have to change one NIS map if a new employee joins the IT department. You could use a similar approach for the less important servers by replacing the old +::::::::: in their local version of /etc/master.passwd with something like this: +@IT_EMP::::::::: +@IT_APP::::::::: +:::::::::/sbin/nologin The corresponding lines for the normal workstations could be: +@IT_EMP::::::::: +@USERS::::::::: +:::::::::/sbin/nologin And everything would be fine until there is a policy change a few weeks later: The IT department starts hiring interns. The IT interns are allowed to use the normal workstations and the less important servers; and the IT apprentices are allowed to login onto the main servers. You add a new netgroup IT_INTERN, add the new IT interns to this netgroup and start to change the config on each and every machine... As the old saying goes: Errors in centralized planning lead to global mess. NIS' ability to create netgroups from other netgroups can be used to prevent situations like these. One possibility is the creation of role-based netgroups. For example, you could create a netgroup called BIGSRV to define the login restrictions for the important servers, another netgroup called SMALLSRV for the less important servers and a third netgroup called USERBOX for the normal workstations. Each of these netgroups contains the netgroups that are allowed to login onto these machines. The new entries for your NIS map netgroup should look like this: BIGSRV IT_EMP IT_APP SMALLSRV IT_EMP IT_APP ITINTERN USERBOX IT_EMP ITINTERN USERS This method of defining login restrictions works reasonably well if you can define groups of machines with identical restrictions. Unfortunately, this is the exception and not the rule. Most of the time, you will need the ability to define login restrictions on a per-machine basis. Machine-specific netgroup definitions are the other possibility to deal with the policy change outlined above. In this scenario, the /etc/master.passwd of each box contains two lines starting with ``+''. The first of them adds a netgroup with the accounts allowed to login onto this machine, the second one adds all other accounts with /sbin/nologin as shell. It is a good idea to use the ALL-CAPS version of the machine name as the name of the netgroup. In other words, the lines should look like this: +@BOXNAME::::::::: +:::::::::/sbin/nologin Once you have completed this task for all your machines, you will not have to modify the local versions of /etc/master.passwd ever again. All further changes can be handled by modifying the NIS map. Here is an example of a possible netgroup map for this scenario with some additional goodies. # Define groups of users first IT_EMP (,alpha,test-domain) (,beta,test-domain) IT_APP (,charlie,test-domain) (,delta,test-domain) DEPT1 (,echo,test-domain) (,foxtrott,test-domain) DEPT2 (,golf,test-domain) (,hotel,test-domain) DEPT3 (,india,test-domain) (,juliet,test-domain) ITINTERN (,kilo,test-domain) (,lima,test-domain) D_INTERNS (,able,test-domain) (,baker,test-domain) # # Now, define some groups based on roles USERS DEPT1 DEPT2 DEPT3 BIGSRV IT_EMP IT_APP SMALLSRV IT_EMP IT_APP ITINTERN USERBOX IT_EMP ITINTERN USERS # # And a groups for a special tasks # Allow echo and golf to access our anti-virus-machine SECURITY IT_EMP (,echo,test-domain) (,golf,test-domain) # # machine-based netgroups # Our main servers WAR BIGSRV FAMINE BIGSRV # User india needs access to this server POLLUTION BIGSRV (,india,test-domain) # # This one is really important and needs more access restrictions DEATH IT_EMP # # The anti-virus-machine mentioned above ONE SECURITY # # Restrict a machine to a single user TWO (,hotel,test-domain) # [...more groups to follow] If you are using some kind of database to manage your user accounts, you should be able to create the first part of the map with your database's report tools. This way, new users will automatically have access to the boxes. One last word of caution: It may not always be advisable to use machine-based netgroups. If you are deploying a couple of dozen or even hundreds of identical machines for student labs, you should use role-based netgroups instead of machine-based netgroups to keep the size of the NIS map within reasonable limits. Important Things to Remember There are still a couple of things that you will need to do differently now that you are in an NIS environment. Every time you wish to add a user to the lab, you must add it to the master NIS server only, and you must remember to rebuild the NIS maps. If you forget to do this, the new user will not be able to login anywhere except on the NIS master. For example, if we needed to add a new user jsmith to the lab, we would: &prompt.root; pw useradd jsmith &prompt.root; cd /var/yp &prompt.root; make test-domain You could also run adduser jsmith instead of pw useradd jsmith. Keep the administration accounts out of the NIS maps. You do not want to be propagating administrative accounts and passwords to machines that will have users that should not have access to those accounts. Keep the NIS master and slave secure, and minimize their downtime. If somebody either hacks or simply turns off these machines, they have effectively rendered many people without the ability to login to the lab. This is the chief weakness of any centralized administration system, and it is probably the most important weakness. If you do not protect your NIS servers, you will have a lot of angry users! NIS v1 Compatibility FreeBSD's ypserv has some support for serving NIS v1 clients. FreeBSD's NIS implementation only uses the NIS v2 protocol, however other implementations include support for the v1 protocol for backwards compatibility with older systems. The ypbind daemons supplied with these systems will try to establish a binding to an NIS v1 server even though they may never actually need it (and they may persist in broadcasting in search of one even after they receive a response from a v2 server). Note that while support for normal client calls is provided, this version of ypserv does not handle v1 map transfer requests; consequently, it cannot be used as a master or slave in conjunction with older NIS servers that only support the v1 protocol. Fortunately, there probably are not any such servers still in use today. NIS Servers that are also NIS Clients Care must be taken when running ypserv in a multi-server domain where the server machines are also NIS clients. It is generally a good idea to force the servers to bind to themselves rather than allowing them to broadcast bind requests and possibly become bound to each other. Strange failure modes can result if one server goes down and others are dependent upon it. Eventually all the clients will time out and attempt to bind to other servers, but the delay involved can be considerable and the failure mode is still present since the servers might bind to each other all over again. You can force a host to bind to a particular server by running ypbind with the flag. If you do not want to do this manually each time you reboot your NIS server, you can add the following lines to your /etc/rc.conf: nis_client_enable="YES" # run client stuff as well nis_client_flags="-S NIS domain,server" See &man.ypbind.8; for further information. libscrypt v.s. libdescrypt NIS crypto library One of the most common issues that people run into when trying to implement NIS is crypt library compatibility. If your NIS server is using the DES crypt libraries, it will only support clients that are using DES as well. To check which one your server and clients are using look at the symlinks in /usr/lib. If the machine is configured to use the DES libraries, it will look something like this: &prompt.user; ls -l /usr/lib/*crypt* lrwxrwxrwx 1 root wheel 13 Jul 15 08:55 libcrypt.a@ -> libdescrypt.a lrwxrwxrwx 1 root wheel 14 Jul 15 08:55 libcrypt.so@ -> libdescrypt.so lrwxrwxrwx 1 root wheel 16 Jul 15 08:55 libcrypt.so.2@ -> libdescrypt.so.2 lrwxrwxrwx 1 root wheel 15 Jul 15 08:55 libcrypt_p.a@ -> libdescrypt_p.a -r--r--r-- 1 root wheel 13018 Nov 8 14:27 libdescrypt.a lrwxr-xr-x 1 root wheel 16 Nov 8 14:27 libdescrypt.so@ -> libdescrypt.so.2 -r--r--r-- 1 root wheel 12965 Nov 8 14:27 libdescrypt.so.2 -r--r--r-- 1 root wheel 14750 Nov 8 14:27 libdescrypt_p.a If the machine is configured to use the standard FreeBSD MD5 crypt libraries they will look something like this: &prompt.user; ls -l /usr/lib/*crypt* lrwxrwxrwx 1 root wheel 13 Jul 15 08:55 libcrypt.a@ -> libscrypt.a lrwxrwxrwx 1 root wheel 14 Jul 15 08:55 libcrypt.so@ -> libscrypt.so lrwxrwxrwx 1 root wheel 16 Jul 15 08:55 libcrypt.so.2@ -> libscrypt.so.2 lrwxrwxrwx 1 root wheel 15 Jul 15 08:55 libcrypt_p.a@ -> libscrypt_p.a -r--r--r-- 1 root wheel 6194 Nov 8 14:27 libscrypt.a lrwxr-xr-x 1 root wheel 14 Nov 8 14:27 libscrypt.so@ -> libscrypt.so.2 -r--r--r-- 1 root wheel 7579 Nov 8 14:27 libscrypt.so.2 -r--r--r-- 1 root wheel 6684 Nov 8 14:27 libscrypt_p.a If you have trouble authenticating on an NIS client, this is a pretty good place to start looking for possible problems. If you want to deploy an NIS server for a heterogenous network, you will probably have to use DES on all systems because it is the lowest common standard. Greg Sutter Written by DHCP What Is DHCP? Dynamic Host Configuration Protocol DHCP Internet Software Consortium (ISC) DHCP, the Dynamic Host Configuration Protocol, describes the means by which a system can connect to a network and obtain the necessary information for communication upon that network. FreeBSD uses the ISC (Internet Software Consortium) DHCP implementation, so all implementation-specific information here is for use with the ISC distribution. What this Section Covers This section attempts to describe only the parts of the DHCP system that are integrated with FreeBSD; consequently, the server portions are not described. The DHCP manual pages, in addition to the references below, are useful resources. How It Works UDP When dhclient, the DHCP client, is executed on the client machine, it begins broadcasting requests for configuration information. By default, these requests are on UDP port 68. The server replies on UDP 67, giving the client an IP address and other relevant network information such as netmask, router, and DNS servers. All of this information comes in the form of a DHCP "lease" and is only valid for a certain time (configured by the DHCP server maintainer). In this manner, stale IP addresses for clients no longer connected to the network can be automatically reclaimed. DHCP clients can obtain a great deal of information from the server. An exhaustive list may be found in &man.dhcp-options.5;. FreeBSD Integration FreeBSD fully integrates the ISC DHCP client, dhclient. DHCP client support is provided within both the installer and the base system, obviating the need for detailed knowledge of network configurations on any network that runs a DHCP server. dhclient has been included in all FreeBSD distributions since 3.2. sysinstall DHCP is supported by sysinstall. When configuring a network interface within sysinstall, the first question asked is, "Do you want to try DHCP configuration of this interface?" Answering affirmatively will execute dhclient, and if successful, will fill in the network configuration information automatically. There are two things you must do to have your system use DHCP upon startup: DHCP requirements Make sure that the bpf device is compiled into your kernel. To do this, add pseudo-device bpf to your kernel configuration file, and rebuild the kernel. For more information about building kernels, see . The bpf device is already part of the GENERIC kernel that is supplied with FreeBSD, so if you do not have a custom kernel, you should not need to create one in order to get DHCP working. For those who are particularly security conscious, you should be warned that bpf is also the device that allows packet sniffers to work correctly (although they still have to be run as root). bpf is required to use DHCP, but if you are very sensitive about security, you probably should not add bpf to your kernel in the expectation that at some point in the future you will be using DHCP. Edit your /etc/rc.conf to include the following: ifconfig_fxp0="DHCP" Be sure to replace fxp0 with the designation for the interface that you wish to dynamically configure. If you are using a different location for dhclient, or if you wish to pass additional flags to dhclient, also include the following (editing as necessary): dhcp_program="/sbin/dhclient" dhcp_flags="" DHCP server The DHCP server, dhcpd, is included as part of the net/isc-dhcp3 port in the ports collection. This port contains the full ISC DHCP distribution, consisting of client, server, relay agent and documentation. Files DHCP configuration files /etc/dhclient.conf dhclient requires a configuration file, /etc/dhclient.conf. Typically the file contains only comments, the defaults being reasonably sane. This configuration file is described by the &man.dhclient.conf.5; manual page. /sbin/dhclient dhclient is statically linked and resides in /sbin. The &man.dhclient.8; manual page gives more information about dhclient. /sbin/dhclient-script dhclient-script is the FreeBSD-specific DHCP client configuration script. It is described in &man.dhclient-script.8;, but should not need any user modification to function properly. /var/db/dhclient.leases The DHCP client keeps a database of valid leases in this file, which is written as a log. &man.dhclient.leases.5; gives a slightly longer description. Further Reading The DHCP protocol is fully described in RFC 2131. An informational resource has also been set up at dhcp.org. Ceri Davies Written by
ceri@FreeBSD.org
 Installing And Configuring A DHCP Server What this Section Covers This section provides information on how to configure a FreeBSD system to act as a DHCP server using the ISC (Internet Software Consortium) implementation of the DHCP suite. The server portion of the suite is not provided as part of FreeBSD, and so you will need to install the net/isc-dhcp3 port to provide this service. See for more information on using the ports collection. DHCP Server Installation DHCP installation In order to configure your FreeBSD system as a DHCP server, you will need to ensure that the &man.bpf.4; device is compiled into your kernel. To do this, add pseudo-device bpf to your kernel configuration file, and rebuild the kernel. For more information about building kernels, see . The bpf device is already part of the GENERIC kernel that is supplied with FreeBSD, so you do not need to create a custom kernel in order to get DHCP working. Those who are particularly security conscious should note that bpf is also the device that allows packet sniffers to work correctly (although such programs still need privileged access). bpf is required to use DHCP, but if you are very sensitive about security, you probably should not include bpf in your kernel purely because you expect to use DHCP at some point in the future. The next thing that you will need to do is edit the sample dhcpd.conf which was installed by the net/isc-dhcp3 port. By default, this will be /usr/local/etc/dhcpd.conf.sample, and you should copy this to /usr/local/etc/dhcpd.conf before proceeding to make changes. Configuring the DHCP Server DHCP configuration dhcpd.conf dhcpd.conf is comprised of declarations regarding subnets and hosts, and is perhaps most easily explained using an example : option domain-name "example.com"; option domain-name-servers 192.168.4.100; option subnet-mask 255.255.255.0; default-lease-time 3600; max-lease-time 86400; ddns-update-style none; subnet 192.168.4.0 netmask 255.255.255.0 { range 192.168.4.129 192.168.4.254; option routers 192.168.4.1; } host mailhost { hardware ethernet 02:03:04:05:06:07; fixed-address mailhost.example.com; } This option specifies the domain that will be provided to clients as the default search domain. See &man.resolv.conf.5; for more information on what this means. This option specifies a comma separated list of DNS servers that the client should use. The netmask that will be provided to clients. A client may request a specific length of time that a lease will be valid. Otherwise the server will assign a lease with this expiry value (in seconds). This is the maximum length of time that the server will lease for. Should a client request a longer lease, a lease will be issued, although it will only be valid for max-lease-time seconds. This option specifies whether the DHCP server should attempt to update DNS when a lease is accepted or released. In the ISC implementation, this option is required. This denotes which IP addresses should be used in the pool reserved for allocating to clients. IP addresses between, and including, the ones stated are handed out to clients. Declares the default gateway that will be provided to clients. The hardware MAC address of a host (so that the DHCP server can recognise a host when it makes a request). Specifies that the host should always be given the same IP address. Note that a hostname is OK here, since the DHCP server will resolve the hostname itself before returning the lease information. Once you have finished writing your dhcpd.conf, you can proceed to start the server by issuing the following command: &prompt.root; /usr/local/etc/rc.d/isc-dhcpd.sh start Should you need to make changes to the configuration of your server in the future, it is important to note that sending a SIGHUP signal to dhcpd does not result in the configuration being reloaded, as it does with most daemons. You will need to send a SIGTERM signal to stop the process, and then restart it using the command above. Files DHCP configuration files /usr/local/sbin/dhcpd dhcpd is statically linked and resides in /usr/local/sbin. The dhcpd(8) manual page installed with the port gives more information about dhcpd. /usr/local/etc/dhcpd.conf dhcpd requires a configuration file, /usr/local/etc/dhcpd.conf before it will start providing service to clients. This file needs to contain all the information that should be provided to clients that are being serviced, along with information regarding the operation of the server. This configuration file is described by the dhcpd.conf(5) manual page installed by the port. /var/db/dhcpd.leases The DHCP server keeps a database of leases it has issued in this file, which is written as a log. The manual page dhcpd.leases(5), installed by the port gives a slightly longer description. /usr/local/sbin/dhcrelay dhcrelay is used in advanced environments where one DHCP server forwards a request from a client to another DHCP server on a separate network. The dhcrelay(8) manual page provided with the port contains more detail. Chern Lee Contributed by DNS Overview BIND FreeBSD utilizes, by default, a version of BIND (Berkeley Internet Name Domain), which is the most common implementation of the DNS protocol. DNS is the protocol through which names are mapped to IP addresses, and vice versa. For example, a query for www.FreeBSD.org will receive a reply with the IP address of The FreeBSD Project's web server, whereas, a query for ftp.FreeBSD.org will return the IP address of the corresponding FTP machine. Likewise, the opposite can happen. A query for an IP address can resolve its hostname. It is not necessary to run a name server to perform DNS lookups on a system. DNS DNS is coordinated across the Internet through a somewhat complex system of authoritative root name servers, and other smaller-scale name servers who host and cache individual domain information. This document refers to BIND 8.x, as it is the stable version used in FreeBSD. BIND 9.x in FreeBSD can be installed through the net/bind9 port. RFC1034 and RFC1035 dictates the DNS protocol. Currently, BIND is maintained by the Internet Software Consortium (www.isc.org) Terminology To understand this document, some terms related to DNS must be understood. Term Definition forward DNS mapping of hostnames to IP addresses origin refers to the domain covered for the particular zone file named, bind, name server common names for the BIND name server package within FreeBSD resolver resolver a system process through which a machine queries a name server for zone information reverse DNS reverse DNS the opposite of forward DNS, mapping of IP addresses to hostnames root zone root zone literally, a ., refers to the root, or beginning zone. All zones fall under this, as do all files in fall under the root directory. It is the beginning of the Internet zone hierarchy. zone Each individual domain, subdomain, or area dictated by DNS zones examples Examples of zones: . is the root zone org. is a zone under the root zone example.org is a zone under the org. zone foo.example.org. is a subdomain, a zone under the example.org. zone 1.2.3.in-addr.arpa is a zone referencing all IP addresses which fall under the 3.2.1.* IP space. As one can see, the more specific part of a hostname appears to its left. For example, example.org. is more specific than org., as org. is more specific than the root zone. The layout of each part of a hostname is much like a filesystem: the /dev directory falls within the root, and so on. Reasons to Run a Name Server Name servers usually come in two forms: an authoritative name server, and a caching name server. An authoritative name server is needed when: one wants to serve DNS information to the world, replying authoritatively to queries. a domain, such as example.org, is registered and IP addresses need to be assigned to hostnames under it. an IP address block requires reverse DNS entries (IP to hostname). a backup name server, called a slave, must reply to queries when the primary is down or inaccessible. A caching name server is needed when: a local DNS server may cache and respond more quickly then querying an outside name server. a reduction in overall network traffic is desired (DNS traffic has been measured to account for 5% or more of total Internet traffic). When one queries for www.FreeBSD.org, the resolver usually queries the uplink ISP's name server, and retrieves the reply. With a local, caching DNS server, the query only has to be made once to the outside world by the caching DNS server. Every additional query will not have to look to the outside of the local network, since the information is cached locally. How It Works In FreeBSD, the BIND daemon is called named for obvious reasons. File Description named the BIND daemon ndc name daemon control program /etc/namedb directory where BIND zone information resides /etc/namedb/named.conf daemon configuration file Zone files are usually contained within the /etc/namedb directory, and contain the DNS zone information served by the name server. Starting BIND BIND starting Since BIND is installed by default, configuring it all is relatively simple. To ensure the named daemon is started at boot, put the following modifications in /etc/rc.conf: named_enable="YES" To start the daemon manually (after configuring it) &prompt.root; ndc start Configuration Files BIND configuration files make-localhost Be sure to: &prompt.root; cd /etc/namedb &prompt.root; sh make-localhost to properly create the local reverse DNS zone file in /etc/namedb/localhost.rev. <filename>/etc/namedb/named.conf</filename> // $FreeBSD$ // // Refer to the named(8) manual page for details. If you are ever going // to setup a primary server, make sure you've understood the hairy // details of how DNS is working. Even with simple mistakes, you can // break connectivity for affected parties, or cause huge amount of // useless Internet traffic. options { directory "/etc/namedb"; // In addition to the "forwarders" clause, you can force your name // server to never initiate queries of its own, but always ask its // forwarders only, by enabling the following line: // // forward only; // If you've got a DNS server around at your upstream provider, enter // its IP address here, and enable the line below. This will make you // benefit from its cache, thus reduce overall DNS traffic in the Internet. /* forwarders { 127.0.0.1; }; */ Just as the comment says, to benefit from an uplink's cache, forwarders can be enabled here. Under normal circumstances, a name server will recursively query the Internet looking at certain name servers until it finds the answer it is looking for. Having this enabled will have it query the uplink's name server (or name server provided) first, taking advantage of its cache. If the uplink name server in question is a heavily trafficked, fast name server, enabling this may be worthwhile. 127.0.0.1 will not work here. Change this IP address to a name server at your uplink. /* * If there is a firewall between you and name servers you want * to talk to, you might need to uncomment the query-source * directive below. Previous versions of BIND always asked * questions using port 53, but BIND 8.1 uses an unprivileged * port by default. */ // query-source address * port 53; /* * If running in a sandbox, you may have to specify a different * location for the dumpfile. */ // dump-file "s/named_dump.db"; }; // Note: the following will be supported in a future release. /* host { any; } { topology { 127.0.0.0/8; }; }; */ // Setting up secondaries is way easier and the rough picture for this // is explained below. // // If you enable a local name server, don't forget to enter 127.0.0.1 // into your /etc/resolv.conf so this server will be queried first. // Also, make sure to enable it in /etc/rc.conf. zone "." { type hint; file "named.root"; }; zone "0.0.127.IN-ADDR.ARPA" { type master; file "localhost.rev"; }; zone "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.IP6.INT" { type master; file "localhost.rev"; }; // NB: Do not use the IP addresses below, they are faked, and only // serve demonstration/documentation purposes! // // Example secondary config entries. It can be convenient to become // a secondary at least for the zone where your own domain is in. Ask // your network administrator for the IP address of the responsible // primary. // // Never forget to include the reverse lookup (IN-ADDR.ARPA) zone! // (This is the first bytes of the respective IP address, in reverse // order, with ".IN-ADDR.ARPA" appended.) // // Before starting to setup a primary zone, better make sure you fully // understand how DNS and BIND works, however. There are sometimes // unobvious pitfalls. Setting up a secondary is comparably simpler. // // NB: Don't blindly enable the examples below. :-) Use actual names // and addresses instead. // // NOTE!!! FreeBSD runs bind in a sandbox (see named_flags in rc.conf). // The directory containing the secondary zones must be write accessible // to bind. The following sequence is suggested: // // mkdir /etc/namedb/s // chown bind:bind /etc/namedb/s // chmod 750 /etc/namedb/s For more information on running BIND in a sandbox, see Running named in a sandbox. /* zone "example.com" { type slave; file "s/example.com.bak"; masters { 192.168.1.1; }; }; zone "0.168.192.in-addr.arpa" { type slave; file "s/0.168.192.in-addr.arpa.bak"; masters { 192.168.1.1; }; }; */ In named.conf, these are examples of slave entries for a forward and reverse zone. For each new zone served, a new zone entry must be added to named.conf For example, the simplest zone entry for example.org can look like: zone "example.org" { type master; file "example.org"; }; The zone is a master, as indicated by the statement, holding its zone information in /etc/namedb/example.org indicated by the statement. zone "example.org" { type slave; file "example.org"; }; In the slave case, the zone information is transferred from the master name server for the particular zone, and saved in the file specified. If and when the master server dies or is unreachable, the slave name server will have the transferred zone information and will be able to serve it. Zone Files An example master zone file for example.org (existing within /etc/namedb/example.org) is as follows: $TTL 3600 example.org. IN SOA ns1.example.org. admin.example.org. ( 5 ; Serial 10800 ; Refresh 3600 ; Retry 604800 ; Expire 86400 ) ; Minimum TTL ; DNS Servers @ IN NS ns1.example.org. @ IN NS ns2.example.org. ; Machine Names localhost IN A 127.0.0.1 ns1 IN A 3.2.1.2 ns2 IN A 3.2.1.3 mail IN A 3.2.1.10 @ IN A 3.2.1.30 ; Aliases www IN CNAME @ ; MX Record @ IN MX 10 mail.example.org. Note that every hostname ending in a . is an exact hostname, whereas everything without a trailing . is referenced to the origin. For example, www is translated into www + origin. In our fictitious zone file, our origin is example.org., so www would translate to www.example.org. The format of a zone file follows: recordname IN recordtype value DNS records The most commonly used DNS records: SOA start of zone authority NS an authoritative name server A A host address CNAME the canonical name for an alias MX mail exchanger PTR a domain name pointer (used in reverse DNS) example.org. IN SOA ns1.example.org. admin.example.org. ( 5 ; Serial 10800 ; Refresh after 3 hours 3600 ; Retry after 1 hour 604800 ; Expire after 1 week 86400 ) ; Minimum TTL of 1 day example.org. the domain name, also the origin for this zone file. ns1.example.org. the primary/authoritative name server for this zone admin.example.org. the responsible person for this zone, email address with @ replaced. (admin@example.org becomes admin.example.org) 5 the serial number of the file. this must be incremented each time the zone file is modified. Nowadays, many admins prefer a yyyymmddrr format for the serial number. 2001041002 would mean last modified 04/10/2001, the latter 02 being the second time the zone file has been modified this day. The serial number is important as it alerts slave name servers for a zone when it is updated. @ IN NS ns1.example.org. This is an NS entry. Every name server that is going to reply authoritatively for the zone must have one of these entries. The @ as seen here could have been example.org. The @ translates to the origin. localhost IN A 127.0.0.1 ns1 IN A 3.2.1.2 ns2 IN A 3.2.1.3 mail IN A 3.2.1.10 @ IN A 3.2.1.30 The A record indicates machine names. As seen above, ns1.example.org would resolve to 3.2.1.2. Again, the origin symbol, @, is used here, thus meaning example.org would resolve to 3.2.1.30. www IN CNAME @ The canonical name record is usually used for giving aliases to a machine. In the example, www is aliased to the machine addressed to the origin, or example.org (3.2.1.30). CNAMEs can be used to provide alias hostnames, or round robin one hostname among multiple machines. @ IN MX 10 mail.example.org. The MX record indicates which mail servers are responsible for handling incoming mail for the zone. mail.example.org is the hostname of the mail server, and 10 being the priority of that mail server. One can have several mail servers, with priorities of 3, 2, 1. A mail server attempting to deliver to example.org would first try the highest priority MX, then the second highest, etc, until the mail can be properly delivered. For in-addr.arpa zone files (reverse DNS), the same format is used, except with PTR entries instead of A or CNAME. $TTL 3600 1.2.3.in-addr.arpa. IN SOA ns1.example.org. admin.example.org. ( 5 ; Serial 10800 ; Refresh 3600 ; Retry 604800 ; Expire 3600 ) ; Minimum @ IN NS ns1.example.org. @ IN NS ns2.example.org. 2 IN PTR ns1.example.org. 3 IN PTR ns2.example.org. 10 IN PTR mail.example.org. 30 IN PTR example.org. This file gives the proper IP address to hostname mappings of our above fictitious domain. Caching Name Server BIND caching name server A caching name server is a name server that is not authoritative for any zones. It simply asks queries of its own, and remembers them for later use. To set one up, just configure the name server as usual, omitting any inclusions of zones. Ceri Davies Contributed by Running named in a Sandbox BIND running in a sandbox chroot For added security you may want to run &man.named.8; as an unprivileged user, and configure it to &man.chroot.8; into a sandbox directory. This makes everything outside of the sandbox inaccessible to the named daemon. Should named be compromised, this will help to reduce the damage that can be caused. By default, FreeBSD has a user and a group called bind, intended for this use. Various people would recommend that instead of configuring named to chroot, you should run named inside a &man.jail.8;. This section does not attempt to cover this situation. Since named will not be able to access anything outside of the sandbox (such as shared libraries, log sockets, and so on), there are a number of steps that need to be followed in order to allow named to function correctly. In the following checklist, it is assumed that the path to the sandbox is /etc/namedb and that you have made no prior modifications to the contents of this directory. Perform the following steps as root. Create all directories that named expects to see: &prompt.root; cd /etc/namedb &prompt.root; mkdir -p bin dev etc var/tmp var/run master slave &prompt.root; chown bind:bind slave var/* named only needs write access to these directories, so that is all we give it. Rearrange and create basic zone and configuration files: &prompt.root; cp /etc/localtime etc &prompt.root; mv named.conf etc && ln -sf etc/named.conf &prompt.root; mv named.root master &prompt.root; sh make-localhost && mv localhost.rev localhost-v6.rev master &prompt.root; cat > master/named.localhost $ORIGIN localhost. $TTL 6h @ IN SOA localhost. postmaster.localhost. ( 1 ; serial 3600 ; refresh 1800 ; retry 604800 ; expiration 3600 ) ; minimum IN NS localhost. IN A 127.0.0.1 ^D This allows named to log the correct time to &man.syslogd.8; Build a statically linked copy of named-xfer, and copy it into the sandbox: &prompt.root; cd /usr/src/lib/libisc && make clean all &prompt.root; cd /usr/src/lib/libbind && make clean all &prompt.root; cd /usr/src/libexec/named-xfer && make NOSHARED=yes all &prompt.root; cp named-xfer /etc/namedb/bin && chmod 555 /etc/namedb/bin/named-xfer This step has been reported to fail occasionally. If this happens to you, then issue the command: &prompt.root; cd /usr/src && make cleandir && make cleandir This will clean out any cruft from your source tree, and retrying the steps above should then work. Make a dev/null that named can see and write to: &prompt.root; cd /etc/namedb/dev && mknod null c 2 2 &prompt.root; chmod 666 null Symlink /var/run/ndc to /etc/namedb/var/run/ndc: &prompt.root; ln -sf /etc/namedb/var/run/ndc /var/run/ndc This simply avoids having to specify the option to &man.ndc.8; every time you run it. If this is something that you find useful, you may wish to add this entry to root's crontab, making use of the option. See &man.crontab.5; for more information regarding this. Configure &man.syslogd.8; to create an extra log socket that named can write to. To do this, add -l /etc/namedb/dev/log to the syslogd_flags variable in /etc/rc.conf. Arrange to have named start and chroot itself to the sandbox by adding the following to /etc/rc.conf: named_enable="YES" named_flags="-u bind -g bind -t /etc/namedb /etc/named.conf" Note that the configuration file /etc/named.conf is denoted by a full pathname relative to the sandbox, i.e. in the line above, the file referred to is actually /etc/namedb/etc/named.conf. The next step is to edit /etc/namedb/etc/named.conf so that named knows which zones to load and where to find them on the disk. There follows a commented example (anything not specifically commented here is no different from the setup for a DNS server not running in a sandbox): options { directory "/"; named-xfer "/bin/named-xfer"; version ""; // Don't reveal BIND version query-source address * port 53; }; // ndc control socket controls { unix "/var/run/ndc" perm 0600 owner 0 group 0; }; // Zones follow: zone "localhost" IN { type master; file "master/named.localhost"; allow-transfer { localhost; }; notify no; }; zone "0.0.127.in-addr.arpa" IN { type master; file "master/localhost.rev"; allow-transfer { localhost; }; notify no; }; zone "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.int" { type master; file "master/localhost-v6.rev"; allow-transfer { localhost; }; notify no; }; zone "." IN { type hint; file "master/named.root"; }; zone "private.example.net" in { type master; file "master/private.example.net.db"; allow-transfer { 192.168.10.0/24; }; }; zone "10.168.192.in-addr.arpa" in { type slave; masters { 192.168.10.2; }; file "slave/192.168.10.db"; }; The directory statement is specified as /, since all files that named needs are within this directory (recall that this is equivalent to a normal user's /etc/namedb. Specifies the full path to the named-xfer binary (from named's frame of reference). This is necessary since named is compiled to look for named-xfer in /usr/libexec by default. Specifies the filename (relative to the directory statement above) where named can find the zonefile for this zone. Specifies the filename (relative to the directory statement above) where named should write a copy of the zonefile for this zone after successfully transferring it from the master server. This is why we needed to change the ownership of the directory slave to bind in the setup stages above. After completing the steps above, either reboot your server or restart &man.syslogd.8; and start &man.named.8;, making sure to use the new options specified in syslogd_flags and named_flags. You should now be running a sandboxed copy of named! Security Although BIND is the most common implementation of DNS, there is always the issue of security. Possible and exploitable security holes are sometimes found. It is a good idea to subscribe to CERT and freebsd-security-notifications to stay up to date with the current Internet and FreeBSD security issues. If a problem arises, keeping sources up to date and having a fresh build of named would not hurt. Further Reading BIND/named manual pages: &man.ndc.8; &man.named.8; &man.named.conf.5; Official ISC Bind Page BIND FAQ O'Reilly DNS and BIND 4th Edition RFC1034 - Domain Names - Concepts and Facilities RFC1035 - Domain Names - Implementation and Specification Tom Hukins Contributed by NTP NTP Overview Over time, a computer's clock is prone to drift. As time passes, the computer's clock becomes less accurate. NTP (Network Time Protocol) is one way to ensure your clock is right. Many Internet services rely on, or greatly benefit from, computers' clocks being accurate. For example, a Web server may receive requests to send a file if it has modified since a certain time. Services such as &man.cron.8; run commands at a given time. If the clock is inaccurate, these commands may not run when expected. NTP ntpd FreeBSD ships with the &man.ntpd.8; NTP server which can be used to query other NTP servers to set the clock on your machine or provide time services to others. Choosing Appropriate NTP Servers NTP choosing servers In order to synchronize your clock, you will need to find one or more NTP servers to use. Your network administrator or ISP may have setup an NTP server for this purpose—check their documentation to see if this is the case. There is a list of publicly accessible NTP servers which you can use to find an NTP server near to you. Make sure you are aware of the policy for any servers you choose, and ask for permission if required. Choosing several unconnected NTP servers is a good idea in case one of the servers you are using becomes unreachable or its clock is unreliable. &man.ntpd.8; uses the responses it receives from other servers intelligently—it will favor unreliable servers less than reliable ones. Configuring Your Machine NTP configuration Basic Configuration ntpdate If you only wish to synchronize your clock when the machine boots up, you can use &man.ntpdate.8;. This may be appropriate for some desktop machines which are frequently rebooted and only require infrequent synchronization, but most machines should run &man.ntpd.8;. Using &man.ntpdate.8; at boot time is also a good idea for machines that run &man.ntpd.8;. &man.ntpd.8; changes the clock gradually, whereas &man.ntpdate.8; sets the clock, no matter how great the difference between a machine's current clock setting and the correct time. To enable &man.ntpdate.8; at boot time, add ntpdate_enable="YES" to /etc/rc.conf. You will also need to specify all servers you wish to synchronize with and any flags to be passed to &man.ntpdate.8; in ntpdate_flags. NTP ntp.conf General Configuration NTP is configured by the /etc/ntp.conf file in the format described in &man.ntp.conf.5;. Here is a simple example: server ntplocal.example.com prefer server timeserver.example.org server ntp2a.example.net driftfile /var/db/ntp.drift The server option specifies which servers are to be used, with one server listed on each line. If a server is specified with the prefer argument, as with ntplocal.example.com, that server is preferred over other servers. A response from a preferred server will be discarded if it differs significantly from other servers' responses, otherwise it will be used without any consideration to other responses. The prefer argument is normally used for NTP servers that are known to be highly accurate, such as those with special time monitoring hardware. The driftfile option specifies which file is used to store the system clock's frequency offset. &man.ntpd.8; uses this to automatically compensate for the clock's natural drift, allowing it to maintain a reasonably correct setting even if it is cut off from all external time sources for a period of time. The driftfile option specifies which file is used to store information about previous responses from the NTP servers you are using. This file contains internal information for NTP. It should not be modified by any other process. Controlling Access to Your Server By default, your NTP server will be accessible to all hosts on the Internet. The restrict option in &man.ntp.conf.5; allows you to control which machines can access your server. If you want to deny all machines from accessing your NTP server, add the line restrict default ignore to /etc/ntp.conf. If you only want to allow machines within your own network to synchronize their clocks with your server, but ensure they are not allowed to configure the server or used as peers to synchronize against, add restrict 192.168.1.0 mask 255.255.255.0 notrust nomodify notrap instead, where 192.168.1.0 is an IP address on your network and 255.255.255.0 is your network's netmask. /etc/ntp.conf can contain multiple restrict options. For more details, see the Access Control Support subsection of &man.ntp.conf.5;. Running the NTP Server To ensure the NTP server is started at boot time, add the line xntpd_enable="YES" to /etc/rc.conf. If you wish to pass additional flags to &man.ntpd.8; edit the xntpd_flags parameter in /etc/rc.conf. To start the server without rebooting your machine, run ntpd being sure to specify any additional parameters from xntpd_flags in /etc/rc.conf. For example: &prompt.root; ntpd -p /var/run/ntpd.pid Using &man.ntpd.8; with a temporary Internet connection ntpd does not need a permanent connection to the Internet to function properly. However, if you have a temporary connection that is configured to dial out on demand, it is a good idea to prevent NTP traffic from triggering a dial out or keeping the connection alive. If you are using user PPP, you can use filter directives in /etc/ppp/ppp.conf. For example: set filter dial 0 deny udp src eq 123 # Prevent NTP traffic from initiating dial out set filter dial 1 permit 0 0 set filter alive 0 deny udp src eq 123 # Prevent incoming NTP traffic from keeping the connection open set filter alive 1 deny udp dst eq 123 # Prevent outgoing NTP traffic from keeping the connection open set filter alive 2 permit 0/0 0/0 For more details see the PACKET FILTERING section in &man.ppp.8; and the examples in /usr/share/examples/ppp/. Some Internet access providers block low-numbered ports, preventing NTP from functioning since replies never reach your machine. Further Information Documentation for the NTP server can be found in /usr/share/doc/ntp/ in HTML format. Chern Lee Contributed by Network Address Translation Overview natd FreeBSD's Network Address Translation daemon, commonly known as &man.natd.8; is a daemon that accepts incoming raw IP packets, changes the source to the local machine and re-injects these packets back into the outgoing IP packet stream. natd does this by changing the source IP address and port such that when data is received back, it is able to determine the original location of the data and forward it back to its original requester. Internet connection sharing IP masquerading The most common use of NAT is to perform what is commonly known as Internet Connection Sharing. Setup Due to the diminishing IP space in IPv4, and the increased number of users on high-speed consumer lines such as cable or DSL, people are increasingly in need of an Internet Connection Sharing solution. The ability to connect several computers online through one connection and IP address makes &man.natd.8; a reasonable choice. Most commonly, a user has a machine connected to a cable or DSL line with one IP address and wishes to use this one connected computer to provide Internet access to several more over a LAN. To do this, the FreeBSD machine on the Internet must act as a gateway. This gateway machine must have two NICs--one for connecting to the Internet router, the other connecting to a LAN. All the machines on the LAN are connected through a hub or switch. _______ __________ ________ | | | | | | | Hub |-----| Client B |-----| Router |----- Internet |_______| |__________| |________| | ____|_____ | | | Client A | |__________| Network Layout A setup like this is commonly used to share an Internet connection. One of the LAN machines is connected to the Internet. The rest of the machines access the Internet through that gateway machine. kernel configuration Configuration The following options must be in the kernel configuration file: options IPFIREWALL options IPDIVERT Additionally, at choice, the following may also be suitable: options IPFIREWALL_DEFAULT_TO_ACCEPT options IPFIREWALL_VERBOSE The following must be in /etc/rc.conf: gateway_enable="YES" firewall_enable="YES" firewall_type="OPEN" natd_enable="YES" natd_interface="fxp0" natd_flags="" gateway_enable="YES" Sets up the machine to act as a gateway. Running sysctl -w net.inet.ip.forwarding=1 would have the same effect. firewall_enable="YES" Enables the firewall rules in /etc/rc.firewall at boot. firewall_type="OPEN" This specifies a predefined firewall ruleset that allows anything in. See /etc/rc.firewall for additional types. natd_interface="fxp0" Indicates which interface to forward packets through (the interface connected to the Internet). natd_flags="" Any additional configuration options passed to &man.natd.8; on boot. Having the previous options defined in /etc/rc.conf would run natd -interface fxp0 at boot. This can also be run manually. Each machine and interface behind the LAN should be assigned IP address numbers in the private network space as defined by RFC 1918 and have a default gateway of the natd machine's internal IP address. For example, client a and b behind the LAN have IP addresses of 192.168.0.2 and 192.168.0.3, while the natd machine's LAN interface has an IP address of 192.168.0.1. Client a and b's default gateway must be set to that of the natd machine, 192.168.0.1. The natd machine's external, or Internet interface does not require any special modification for natd to work. Port Redirection The drawback with natd is that the LAN clients are not accessible from the Internet. Clients on the LAN can make outgoing connections to the world but cannot receive incoming ones. This presents a problem if trying to run Internet services on one of the LAN client machines. A simple way around this is to redirect selected Internet ports on the natd machine to a LAN client. For example, an IRC server runs on Client A, and a web server runs on Client B. For this to work properly, connections received on ports 6667 (irc) and 80 (web) must be redirected to the respective machines. The -redirect_port must be passed to &man.natd.8; with the proper options. The syntax is as follows: -redirect_port proto targetIP:targetPORT[-targetPORT] [aliasIP:]aliasPORT[-aliasPORT] [remoteIP[:remotePORT[-remotePORT]]] In the above example, the argument should be: -redirect_port tcp 192.168.0.2:6667 6667 -redirect_port tcp 192.168.0.3:80 80 This will redirect the proper tcp ports to the LAN client machines. The -redirect_port argument can be used to indicate port ranges over individual ports. For example, tcp 192.168.0.2:2000-3000 2000-3000 would redirect all connections received on ports 2000 to 3000 to ports 2000 to 3000 on Client A. These options can be used when directly running &man.natd.8; or placed within the natd_flags="" option in /etc/rc.conf. For further configuration options, consult &man.natd.8; Address Redirection address redirection Address redirection is useful if several IP addresses are available, yet they must be on one machine. With this, &man.natd.8; can assign each LAN client its own external IP address. &man.natd.8; then rewrites outgoing packets from the LAN clients with the proper external IP address and redirects all traffic incoming on that particular IP address back to the specific LAN client. This is also known as static NAT. For example, the IP addresses 128.1.1.1, 128.1.1.2, and 128.1.1.3 belong to the natd gateway machine. 128.1.1.1 can be used as the natd gateway machine's external IP address, while 128.1.1.2 and 128.1.1.3 are forwarded back to LAN clients A and B. The -redirect_address syntax is as follows: localIP The internal IP address of the LAN client. publicIP The external IP address corresponding to the LAN client. In the example, this argument would read: Like -redirect_port, these arguments are also placed within natd_flags of /etc/rc.conf. With address redirection, there is no need for port redirection since all data received on a particular IP address is redirected. The external IP addresses on the natd machine must be active and aliased to the external interface. Look at &man.rc.conf.5; to do so. Chern Lee Contributed by inetd <quote>Super-Server</quote> Overview &man.inetd.8; is referred to as the Internet Super-Server because it manages connections for several daemons. Programs that provide network service are commonly known as daemons. inetd serves as a managing server for other daemons. When a connection is received by inetd, it determines which daemon the connection is destined for, spawns the particular daemon and delegates the socket to it. Running one instance of inetd reduces the overall system load as compared to running each daemon individually in stand-alone mode. Primarily, inetd is used to spawn other daemons, but several trivial protocols are handled directly, such as chargen, auth, and daytime. This section will cover the basics in configuring inetd through its command-line options and its configuration file, /etc/inetd.conf. Settings inetd is initialized through the /etc/rc.conf system. The inetd_enable option is set to NO by default, but is often times turned on by sysinstall with the medium security profile. Placing: inetd_enable="YES" or inetd_enable="NO" into /etc/rc.conf can enable or disable inetd starting at boot time. Additionally, different command-line options can be passed to inetd via the inetd_flags option. Command-Line Options inetd sypnosis: -d Turn on debugging. -l Turn on logging of successful connections. -w Turn on TCP Wrapping for external services (on by default). -W Turn on TCP Wrapping for internal services which are built into inetd (on by default). -c maximum Specify the default maximum number of simultaneous invocations of each service; the default is unlimited. May be overridden on a per-service basis with the parameter. -C rate Specify the default maximum number of times a service can be invoked from a single IP address in one minute; the default is unlimited. May be overridden on a per-service basis with the parameter. -R rate Specify the maximum number of times a service can be invoked in one minute; the default is 256. A rate of 0 allows an unlimited number of invocations. -a Specify one specific IP address to bind to. Alternatively, a hostname can be specified, in which case the IPv4 or IPv6 address which corresponds to that hostname is used. Usually a hostname is specified when inetd is run inside a &man.jail.8;, in which case the hostname corresponds to the &man.jail.8; environment. When hostname specification is used and both IPv4 and IPv6 bindings are desired, one entry with the appropriate protocol type for each binding is required for each service in /etc/inetd.conf. For example, a TCP-based service would need two entries, one using ``tcp4'' for the protocol and the other using ``tcp6''. -p Specify an alternate file in which to store the process ID. These options can be passed to inetd using the inetd_flags option in /etc/rc.conf. By default, inetd_flags is set to -wW, which turns on TCP wrapping for inetd's internal and external services. For novice users, these parameters usually do not need to be modified or even entered in /etc/rc.conf. An external service is a daemon outside of inetd, which is invoked when a connection is received for it. On the other hand, an internal service is one that inetd has the facility of offering within itself. <filename>inetd.conf</filename> Configuration of inetd is controlled through the /etc/inetd.conf file. When a modification is made to /etc/inetd.conf, inetd can be forced to re-read its configuration file by sending a HangUP signal to the inetd process as shown: Sending <application>inetd</application> a HangUP Signal &prompt.root; kill -HUP `cat /var/run/inetd.pid` Each line of the configuration file specifies an individual daemon. Comments in the file are preceded by a #. The format of /etc/inetd.conf is as follows: service-name socket-type protocol {wait|nowait}[/max-child[/max-connections-per-ip-per-minute]] user[:group][/login-class] server-program server-program-arguments An example entry for the ftpd daemon using IPv4: ftp stream tcp nowait root /usr/libexec/ftpd ftpd -l service-name This is the service name of the particular daemon. It must correspond to a service listed in /etc/services. This determines which port inetd must listen to. If a new service is being created, it must be placed in /etc/services first. socket-type Either stream, dgram, raw, or seqpacket. stream must be used for connection-based, TCP daemons, while dgram is used for daemons utilizing the UDP transport protocol. protocol One of the following: Protocol Explanation tcp, tcp4 TCP IPv4 udp, udp4 UDP IPv4 tcp6 TCP IPv6 udp6 UDP IPv6 tcp46 Both TCP IPv4 and v6 udp46 Both UDP IPv4 and v6 {wait|nowait}[/max-child[/max-connections-per-ip-per-minute]] indicates whether the daemon invoked from inetd is able to handle its own socket or not. socket types must use the wait option, while stream socket daemons, which are usually multi-threaded, should use . usually hands off multiple sockets to a single daemon, while spawns a child daemon for each new socket. The maximum number of child daemons inetd may spawn can be set using the option. If a limit of ten instances of a particular daemon is needed, a /10 would be placed after . In addition to , another option limiting the maximum connections from a single place to a particular daemon can be enabled. does just this. A value of ten here would limit any particular IP address connecting to a particular service to ten attempts per minute. This is useful to prevent intentional or unintentional resource consumption and Denial of Service (DoS) attacks to a machine. In this field, or is mandatory. and are optional. A stream-type multi-threaded daemon without any or limits would simply be: nowait The same daemon with a maximum limit of ten daemons would read: nowait/10 Additionally, the same setup with a limit of twenty connections per IP address per minute and a maximum total limit of ten child daemons would read: nowait/10/20 These options are all utilized by the default settings of the fingerd daemon, as seen here: finger stream tcp nowait/3/10 nobody /usr/libexec/fingerd fingerd -s user The user is the username that the particular daemon should run as. Most commonly, daemons run as the root user. For security purposes, it is common to find some servers running as the daemon user, or the least privileged nobody user. server-program The full path of the daemon to be executed when a connection is received. If the daemon is a service provided by inetd internally, then should be used. server-program-arguments This works in conjunction with by specifying the arguments, starting with argv[0], passed to the daemon on invocation. If mydaemon -d is the command line, mydaemon -d would be the value of . Again, if the daemon is an internal service, use here. Security Depending on the security profile chosen at install, many of inetd's daemons may be enabled by default. If there is no apparent need for a particular daemon, disable it! Place a # in front of the daemon in question, and send a hangup signal to inetd. Some daemons, such as fingerd, may not be desired at all because they provide an attacker with too much information. Some daemons are not security-conscious and have long, or non-existent timeouts for connection attempts. This allows an attacker to slowly send connections to a particular daemon, thus saturating available resources. It may be a good idea to place and limitations on certain daemons. By default, TCP wrapping is turned on. Consult the &man.hosts.access.5; manual page for more information on placing TCP restrictions on various inetd invoked daemons. Miscellaneous daytime, time, echo, discard, chargen, and auth are all internally provided services of inetd. The auth service provides identity (ident, identd) network services, and is configurable to a certain degree. Consult the &man.inetd.8; manual page for more in-depth information. Parallel Line IP (PLIP) PLIP Parallel Line IP PLIP lets us run TCP/IP between parallel ports. It is useful on machines without network cards, or to install on laptops. In this section, we will discuss: Creating a parallel (laplink) cable. connecting two computers with PLIP. Creating a Parallel Cable You can purchase a parallel cable at most computer supply stores. If you can't do that, or you just want to know how it's done, here's how you make one out of a normal parallel printer cable. Wiring a parallel cable for networking A-name A-End B-End Descr. Post/Bit DATA0 -ERROR 2 15 15 2 Data 0/0x01 1/0x08 DATA1 +SLCT 3 13 13 3 Data 0/0x02 1/0x10 DATA2 +PE 4 12 12 4 Data 0/0x04 1/0x20 DATA3 -ACK 5 10 10 5 Strobe 0/0x08 1/0x40 DATA4 BUSY 6 11 11 6 Data 0/0x10 1/0x80 GND 18-25 18-25 GND -
Setting up PLIP Get a laplink cable. Confirm that both computers have a kernel with lpt driver support. &prompt.root; dmesg | grep lp lpt0 at 0x378-0x37f irq 7 on isa lpt0: Interrupt-driven lp0: TCP/IP capable interface Plug in the laplink cable into the parallel interface on both computers. Configure the network interface parameters for lp0 on both sites as root. For example, if you want connect the host host1 with host2 host1 <-----> host2 IP Address 10.0.0.1 10.0.0.2 Configure the interface on host1 by doing: &prompt.root; ifconfig lp0 10.0.0.1 10.0.0.2 Configure the interface on host2 by doing: &prompt.root; ifconfig lp0 10.0.0.2 10.0.0.1 You now should have a working connection. Please read the manual pages &man.lp.4; and &man.lpt.4; for more details. You should also add both hosts to /etc/hosts. 127.0.0.1 localhost.my.domain localhost 10.0.0.1 host1.my.domain host1 10.0.0.2 host2.my.domain To confirm the connection works, go to each host and ping the other. For example, on host1: &prompt.root; ifconfig lp0 lp0: flags=8851<UP,POINTOPOINT,RUNNING,SIMPLEX,MULTICAST> mtu 1500 inet 10.0.0.1 --> 10.0.0.2 netmask 0xff000000 &prompt.root; netstat -r Routing tables Internet: Destination Gateway Flags Refs Use Netif Expire host2 host1 UH 4 127592 lp0 &prompt.root; ping -c 4 host2 PING host2 (10.0.0.2): 56 data bytes 64 bytes from 10.0.0.2: icmp_seq=0 ttl=255 time=2.774 ms 64 bytes from 10.0.0.2: icmp_seq=1 ttl=255 time=2.530 ms 64 bytes from 10.0.0.2: icmp_seq=2 ttl=255 time=2.556 ms 64 bytes from 10.0.0.2: icmp_seq=3 ttl=255 time=2.714 ms --- host2 ping statistics --- 4 packets transmitted, 4 packets received, 0% packet loss round-trip min/avg/max/stddev = 2.530/2.643/2.774/0.103 ms diff --git a/en_US.ISO8859-1/books/handbook/basics/chapter.sgml b/en_US.ISO8859-1/books/handbook/basics/chapter.sgml index 6c94b7ebd6..8cd112eda8 100644 --- a/en_US.ISO8859-1/books/handbook/basics/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/basics/chapter.sgml @@ -1,1479 +1,1479 @@ Chris Shumway Rewritten by Unix Basics Synopsis basics The following chapter will cover the basic commands and functionality of the FreeBSD operating system. Much of this material is relevant for any Unix-like operating system. Feel free to skim over this chapter if you are familiar with the material. If you are new to FreeBSD, then you will definitely want to read through this chapter carefully. After reading this chapter, you will know: How Unix file permissions work. What processes, daemons, and signals are. What a shell is, and how to change your default login environment. How to use basic text editors. How to read manual pages for more information. Permissions Unix FreeBSD, being a direct descendant of BSD Unix, is based on several key Unix concepts. The first, and most pronounced, is that FreeBSD is a multi-user operating system. The system can handle several users all working simultaneously on completely unrelated tasks. The system is responsible for properly sharing and managing requests for hardware devices, peripherals, memory, and CPU time evenly to each user. Because the system is capable of supporting multiple users, everything the system manages has a set of permissions governing who can read, write, and execute the resource. These permissions are stored as two octets broken into three pieces, one for the owner of the file, one for the group that the file belongs to, and one for everyone else. This numerical representation works like this: permissions file permissions Value Permission Directory Listing 0 No read, no write, no execute --- 1 No read, no write, execute --x 2 No read, write, no execute -w- 3 No read, write, execute -wx 4 Read, no write, no execute r-- 5 Read, no write, execute r-x 6 Read, write, no execute rw- 7 Read, write, execute rwx ls directories You can use the command line argument to &man.ls.1; to view a long directory listing that includes a column with information about a file's permissions for the owner, group, and everyone else. Here is how the first column of ls -l is broken up: -rw-r--r-- The first character, from left to right, is a special character that tells if this is a regular file, a directory, a special character or block device, a socket, or any other special pseudo-file device. The next three characters, designated as rw- gives the permissions for the owner of the file. The next three characters, r-- gives the permissions for the group that the file belongs to. The final three characters, r--, gives the permissions for the rest of the world. A dash means that the permission is turned off. In the case of this file, the permissions are set so the owner can read and write to the file, the group can read the file, and the rest of the world can only read the file. According to the table above, the permissions for this file would be 644, where each digit represents the three parts of the file's permission. This is all well and good, but how does the system control permissions on devices? FreeBSD actually treats most hardware devices as a file that programs can open, read, and write data to just like any other file. These special device files are stored on the /dev directory. Directories are also treated as files. They have read, write, and execute permissions. The executable bit for a directory has a slightly different meaning than that of files. When a directory is marked executable, it means it can be moved into, i.e. it is possible to cd into it. This also means that within the directory it is possible to access files whose names are known (subject, of course, to the permissions on the files themselves). In particular, in order to able to perform a directory listing, read permission must be set on the directory, whilst to delete a file that one knows the name of, it is necessary to have write and execute permissions to the directory containing the file. There are more to permissions, but they are primarily used in special circumstances such as setuid binaries and sticky directories. If you want more information on file permissions and how to set them, be sure to look at the &man.chmod.1; man page. Directory Structure directory hierarchy The FreeBSD directory hierarchy is fundamental to obtaining an overall understanding of the system. The most important concept to grasp is that of the root directory, /. This directory is the first one mounted at boot time and it contains the base system necessary to prepare the operating system for multi-user operation. The root - directory also contains mount points for every other file system + directory also contains mount points for every other filesystem that you may want to mount. - A mount point is a directory where additional file systems can - be grafted onto the root file system. Standard mount points include + A mount point is a directory where additional filesystems can + be grafted onto the root filesystem. Standard mount points include /usr, /var, /mnt, and /cdrom. These directories are usually referenced to entries in the file /etc/fstab. /etc/fstab is - a table of various file systems and mount points for reference by the - system. Most of the file systems in /etc/fstab + a table of various filesystems and mount points for reference by the + system. Most of the filesystems in /etc/fstab are mounted automatically at boot time from the script &man.rc.8; unless they contain the option. Consult the &man.fstab.5; manual page for more information on the format of the /etc/fstab file and the options it contains. A complete description of the filesystem hierarchy is available in &man.hier.7;. For now, a brief overview of the most common directories will suffice. Directory Description / Root directory of the filesystem. /bin/ User utilities fundamental to both single-user and multi-user environments. /boot/ Programs and configuration files used during operating system bootstrap. /boot/defaults/ Default bootstrapping configuration files; see &man.loader.conf.5;. /dev/ Device nodes; see &man.intro.4;. /etc/ System configuration files and scripts. /etc/defaults/ Default system configuration files; see &man.rc.8;. /etc/mail/ Configuration files for mail transport agents such as &man.sendmail.8;. /etc/namedb/ named configuration files; see &man.named.8;. /etc/periodic/ Scripts that are run daily, weekly, and monthly, via &man.cron.8;; see &man.periodic.8;. /etc/ppp/ ppp configuration files; see &man.ppp.8;. /mnt/ Empty directory commonly used by system administrators as a temporary mount point. /proc/ - Process file system; see &man.procfs.5;, + Process filesystem; see &man.procfs.5;, &man.mount.procfs.8;. /root/ Home directory for the root account. /sbin/ System programs and administration utilities fundamental to both single-user and multi-user environments. /stand/ Programs used in a standalone environment. /tmp/ Temporary files, usually a &man.mfs.8; memory-based filesystem (the contents of /tmp are usually NOT preserved across a system reboot). /usr/ The majority of user utilities and applications. /usr/bin/ Common utilities, programming tools, and applications. /usr/include/ Standard C include files. /usr/lib/ Archive libraries. /usr/libdata/ Miscellaneous utility data files. /usr/libexec/ System daemons & system utilities (executed by other programs). /usr/local/ Local executables, libraries, etc. Also used as the default destination for the FreeBSD ports framework. Within /usr/local, the general layout sketched out by &man.hier.7; for /usr should be used. Exceptions are the man directory is directly under /usr/local rather than under /usr/local/share. Ports documentation is in share/doc/port. /usr/obj/ Architecture-specific target tree produced by building the /usr/src tree. /usr/ports The FreeBSD ports collection (optional). /usr/sbin/ System daemons & system utilities (executed by users). /usr/share/ Architecture-independent files. /usr/src/ BSD and/or local source files. /usr/X11R6/ X11R6 distribution executables, libraries, etc (optional). /var/ Multi-purpose log, temporary, transient, and spool files. /var/log/ Miscellaneous system log files. /var/mail/ User mailbox files. /var/spool/ Miscellaneous printer and mail system spooling directories. /var/tmp/ Temporary files that are kept between system reboots. /var/yp NIS maps. Mounting and Unmounting Filesystems The filesystem is best visualized as a tree, rooted, as it were, at /. /dev, /usr, and the other directories in the root directory are branches, which may have their own branches, such as /usr/local, and so on. root filesystem There are various reasons to house some of these directories on separate filesystems. /var contains the directories log/, spool/, and various types of temporary files, and as such, may get filled up. Filling up the root filesystem is not a good idea, so splitting /var from / is often favorable. Another common reason to contain certain directory trees on other filesystems is if they are to be housed on separate physical disks, or are separate virtual disks, such as Network File System mounts, or CDROM drives. The <filename>fstab</filename> File filesystems mounted with fstab During the boot process, filesystems listed in /etc/fstab are automatically mounted (unless they are listed with the option). The /etc/fstab file contains a list of lines of the following format: device /mount-point fstype options dumpfreq passno device A device name (which should exist), as explained in Disk naming conventions above. mount-point A directory (which should exist), on which to mount the filesystem. fstype The filesystem type to pass to &man.mount.8;. The default FreeBSD filesystem is ufs. options Either for read-write filesystems, or for read-only filesystems, followed by any other options that may be needed. A common option is for filesystems not normally mounted during the boot sequence. Other options are listed in the &man.mount.8; manual page. dumpfreq This is used by dump to determine which filesystems require dumping. If the field is missing, a value of zero is assumed. passno This determines the order in which filesystems should be checked. Filesystems that should be skipped should have their passno set to zero. The root filesystem (which needs to be checked before everything else) should have it's passno set to one, and other filesystems' passno should be set to values greater than one. If more than one filesystems have the same passno then &man.fsck.8; will attempt to check filesystems in parallel if possible. The mount Command filesystems mounting The &man.mount.8; command is what is ultimately used to mount filesystems. In its most basic form, you use: &prompt.root; mount device mountpoint There are plenty of options, as mentioned in the &man.mount.8; manual page, but the most common are: Mount Options Mount all the filesystems listed in /etc/fstab. Exceptions are those marked as noauto, excluded by the flag, or those that are already mounted. Do everything except for the actual system call. This option is useful in conjunction with the flag to determine what the mount is actually trying to do. Force the mount of an unclean filesystem (dangerous), or forces the revocation of write access when downgrading a filesystem's mount status from read-write to read-only. Mount the filesystem read-only. This is identical to using the argument to the option. fstype Mount the given filesystem as the given filesystem type, or mount only filesystems of the given type, if given the option. ufs is the default filesystem type. Update mount options on the filesystem. Be verbose. Mount the filesystem read-write. The option takes a comma-separated list of the options, including the following: nodev Do not interpret special devices on the filesystem. This is a useful security option. noexec Do not allow execution of binaries on this filesystem. This is also a useful security option. nosuid Do not interpret setuid or setgid flags on the filesystem. This is also a useful security option. The <command>umount</command> Command filesystems unmounting The &man.umount.8; command takes, as a parameter, one of a mountpoint, a device name, or the or option. All forms take to force unmounting, and for verbosity. Be warned that is not generally a good idea. Forcibly unmounting filesystems might crash the computer or damage data on the filesystem. and are used to unmount all mounted filesystems, possibly modified by the filesystem types listed after . , however, does not attempt to unmount the root filesystem. Processes FreeBSD is a multi-tasking operating system. This means that it seems as though more than one program is running at once. Each program running at any one time is called a process. Every command you run will start at least one new process, and there are a number of system processes that run all the time, keeping the system functional. Each process is uniquely identified by a number called a process ID, or PID, and, like files, each process also has one owner and group. The owner and group information is used to determine what files and devices the process can open, using the file permissions discussed earlier. Most processes also have a parent process. The parent process is the process that started them. For example, if you are typing commands to the shell then the shell is a process, and any commands you run are also processes. Each process you run in this way will have your shell as its parent process. The exception to this is a special process called init. init is always the first process, so its PID is always 1. init is started automatically by the kernel when FreeBSD starts. Two commands are particularly useful to see the processes on the system, &man.ps.1; and &man.top.1;. The &man.ps.1; command is used to show a static list of the currently running processes, and can show their PID, how much memory they are using, the command line they were started with, and so on. The &man.top.1; command displays all the running processes, and updates the display every few seconds, so that you can interactively see what your computer is doing. By default, &man.ps.1; only shows you the commands that are running and are owned by you. For example: &prompt.user; ps PID TT STAT TIME COMMAND 298 p0 Ss 0:01.10 tcsh 7078 p0 S 2:40.88 xemacs mdoc.xsl (xemacs-21.1.14) 37393 p0 I 0:03.11 xemacs freebsd.dsl (xemacs-21.1.14) 48630 p0 S 2:50.89 /usr/local/lib/netscape-linux/navigator-linux-4.77.bi 48730 p0 IW 0:00.00 (dns helper) (navigator-linux-) 72210 p0 R+ 0:00.00 ps 390 p1 Is 0:01.14 tcsh 7059 p2 Is+ 1:36.18 /usr/local/bin/mutt -y 6688 p3 IWs 0:00.00 tcsh 10735 p4 IWs 0:00.00 tcsh 20256 p5 IWs 0:00.00 tcsh 262 v0 IWs 0:00.00 -tcsh (tcsh) 270 v0 IW+ 0:00.00 /bin/sh /usr/X11R6/bin/startx -- -bpp 16 280 v0 IW+ 0:00.00 xinit /home/nik/.xinitrc -- -bpp 16 284 v0 IW 0:00.00 /bin/sh /home/nik/.xinitrc 285 v0 S 0:38.45 /usr/X11R6/bin/sawfish As you can see in this example, the output from &man.ps.1; is organized into a number of columns. PID is the process ID discussed earlier. PIDs are assigned starting from 1, go up to 99999, and wrap around back to the beginning when you run out. TT shows the tty the program is running on, and can safely be ignored for the moment. STAT shows the program's state, and again, can be safely ignored. TIME is the amount of time the program has been running on the CPU—this is not necessarily the elapsed time since you started the program, as some programs spend a lot of time waiting for things to happen before they need to spend time on the CPU. Finally, COMMAND is the command line that was used to run the program. &man.ps.1; supports a number of different options to change the information that is displayed. One of the most useful sets is auxww. displays information about all the running processes, not just your own. displays the username of the process' owner, as well as memory usage. displays information about daemon processes, and causes &man.ps.1; to display the full command line, rather than truncating it once it gets too long to fit on the screen. The output from &man.top.1; is similar. A sample session looks like this: &prompt.user; top last pid: 72257; load averages: 0.13, 0.09, 0.03 up 0+13:38:33 22:39:10 47 processes: 1 running, 46 sleeping CPU states: 12.6% user, 0.0% nice, 7.8% system, 0.0% interrupt, 79.7% idle Mem: 36M Active, 5256K Inact, 13M Wired, 6312K Cache, 15M Buf, 408K Free Swap: 256M Total, 38M Used, 217M Free, 15% Inuse PID USERNAME PRI NICE SIZE RES STATE TIME WCPU CPU COMMAND 72257 nik 28 0 1960K 1044K RUN 0:00 14.86% 1.42% top 7078 nik 2 0 15280K 10960K select 2:54 0.88% 0.88% xemacs-21.1.14 281 nik 2 0 18636K 7112K select 5:36 0.73% 0.73% XF86_SVGA 296 nik 2 0 3240K 1644K select 0:12 0.05% 0.05% xterm 48630 nik 2 0 29816K 9148K select 3:18 0.00% 0.00% navigator-linu 175 root 2 0 924K 252K select 1:41 0.00% 0.00% syslogd 7059 nik 2 0 7260K 4644K poll 1:38 0.00% 0.00% mutt ... The output is split into two sections. The header (the first five lines) shows the PID of the last process to run, the system load averages (which are a measure of how busy the system is), the system uptime (time since the last reboot) and the current time. The other figures in the header relate to how many processes are running (47 in this case), how much memory and swap space has been taken up, and how much time the system is spending in different CPU states. Below that are a series of columns containing similar information to the output from &man.ps.1;. As before you can see the PID, the username, the amount of CPU time taken, and the command that was run. &man.top.1; also defaults to showing you the amount of memory space taken by the process. This is split into two columns, one for total size, and one for resident size—total size is how much memory the application has needed, and the resident size is how much it is actually using at the moment. In this example you can see that Netscape has required almost 30 MB of RAM, but is currently only using 9 MB. &man.top.1; automatically updates this display every two seconds; this can be changed with the option. Daemons, Signals, and Killing Processes When you run an editor it is easy to control the editor, tell it to load files, and so on. You can do this because the editor provides facilities to do so, and because the editor is attached to a terminal. Some programs are not designed to be run with continuous user input, and so they disconnect from the terminal at the first opportunity. For example, a web server spends all day responding to web requests, it normally does not need any input from you. Programs that transport email from site to site are another example of this class of application. We call these programs daemons. Daemons were characters in Greek mythology; neither good or evil, they were little attendant spirits that, by and large, did useful things for mankind. Much like the web servers and mail servers of today do useful things. This is why the BSD mascot has, for a long time, been the cheerful looking daemon with sneakers and a pitchfork. There is a convention to name programs that normally run as daemons with a trailing d. BIND is the Berkeley Internet Name Daemon (and the actual program that executes is called named), the Apache web server program is called httpd, the line printer spooling daemon is lpd and so on. This is a convention, not a hard and fast rule; for example, the main mail daemon for the Sendmail application is called sendmail, and not maild, as you might imagine. Sometimes you will need to communicate with a daemon process. These communications are called signals, and you can communicate with daemons (or with any running process) by sending it a signal. There are a number of different signals that you can send—some of them have a specific meaning, others are interpreted by the application, and the application's documentation will tell you how that application interprets signals. You can only send a signal to a process that you own. If you send a signal to someone else's process with &man.kill.1; or &man.kill.2; permission will be denied. The exception to this is the root user, who can send signals to everyone's processes. FreeBSD will also send applications signals in some cases. If an application is badly written, and tries to access memory that it is not supposed to, FreeBSD sends the process the Segmentation Violation signal (SIGSEGV). If an application has used the &man.alarm.3; system call to be alerted after a period of time has elapsed then it will be sent the Alarm signal (SIGALRM), and so on. Two signals can be used to stop a process, SIGTERM and SIGKILL. SIGTERM is the polite way to kill a process; the process can catch the signal, realize that you want it to shut down, close any log files it may have open, and generally finish whatever it is doing at the time before shutting down. In some cases a process may even ignore SIGTERM if it is in the middle of some task that can not be interrupted. SIGKILL can not be ignored by a process. This is the I do not care what you are doing, stop right now signal. If you send SIGKILL to a process then FreeBSD will stop that process there and then Not quite true—there are a few things that can not be interrupted. For example, if the process is trying to read from a file that is on another computer on the network, and the other computer has gone away for some reason (been turned off, or the network has a fault), then the process is said to be uninterruptible. Eventually the process will time out, typically after two minutes. As soon as this time out occurs the process will be killed. . The other signals you might want to use are SIGHUP, SIGUSR1, and SIGUSR2. These are general purpose signals, and different applications will do different things when they are sent. Suppose that you have changed your web server's configuration file—you would like to tell the web server to re-read its configuration. You could stop and restart httpd, but this would result in a brief outage period on your web server, which may be undesirable. Most daemons are written to respond to the SIGHUP signal by re-reading their configuration file. So instead of killing and restarting httpd you would send it the SIGHUP signal. Because there is no standard way to respond to these signals, different daemons will have different behavior, so be sure and read the documentation for the daemon in question. Signals are sent using the &man.kill.1; command, as this example shows. Sending a Signal to a Process This example shows how to send a signal to &man.inetd.8;. The &man.inetd.8; configuration file is /etc/inetd.conf, and &man.inetd.8; will re-read this configuration file when it is sent SIGHUP. Find the process ID of the process you want to send the signal to. Do this using &man.ps.1; and &man.grep.1;. The &man.grep.1; command is used to search through output, looking for the string you specify. This command is run as a normal user, and &man.inetd.8; is run as root, so the options must be given to &man.ps.1;. &prompt.user; ps -ax | grep inetd 198 ?? IWs 0:00.00 inetd -wW So the &man.inetd.8; PID is 198. In some cases the grep inetd command might also occur in this output. This is because of the way &man.ps.1; has to find the list of running processes. Use &man.kill.1; to send the signal. Because &man.inetd.8; is being run by root you must use &man.su.1; to become root first. &prompt.user; su Password: &prompt.root; /bin/kill -s HUP 198 In common most with Unix commands, &man.kill.1; will not print any output if it is successful. If you send a signal to a process that you do not own then you will see kill: PID: Operation not permitted. If you mistype the PID you will either send the signal to the wrong process, which could be bad, or, if you are lucky, you will have sent the signal to a PID that is not currently in use, and you will see kill: PID: No such process. Why Use <command>/bin/kill</command>? Many shells provide the kill command as a built in command; that is, the shell will send the signal directly, rather than running /bin/kill. This can be very useful, but different shells have a different syntax for specifying the name of the signal to send. Rather than try to learn all of them, it can be simpler just to use the /bin/kill ... command directly. Sending other signals is very similar, just substitute TERM or KILL in the command line as necessary. Killing random process on the system can be a bad idea. In particular, &man.init.8;, process ID 1, is very special. Running /bin/kill -s KILL 1 is a quick way to shutdown your system. Always double check the arguments you run &man.kill.1; with before you press Return. Shells shells command-line In FreeBSD, a lot of everyday work is done in a command line interface called a shell. A shell's main job is to take commands from the input channel and execute them. A lot of shells also have built in functions to help everyday tasks such a file management, file globing, command line editing, command macros, and environment variables. FreeBSD comes with a set of shells, such as sh, the Bourne Shell, and tcsh, the improved C-shell. Many other shells are available from the FreeBSD Ports Collection, such as zsh and bash. Which shell do you use? It is really a matter of taste. If you are a C programmer you might feel more comfortable with a C-like shell such as tcsh. If you have come from Linux or are new to a Unix command line interface you might try bash. The point is that each shell has unique properties that may or may not work with your preferred working environment, and that you have a choice of what shell to use. One common feature in a shell is file-name completion. Given the typing of the first few letters of a command or filename, you can usually have the shell automatically complete the rest of the command or filename by hitting the Tab key on the keyboard. Here is an example. Suppose you have two files called foobar and foo.bar. You want to delete foo.bar. So what you would type on the keyboard is: rm fo[Tab].[Tab]. The shell would print out rm foo[BEEP].bar. The [BEEP] is the console bell, which is the shell telling me it was unable to totally complete the filename because there is more than one match. Both foobar and foo.bar start with fo, but it was able to complete to foo. If you type in ., then hit Tab again, the shell would be able to fill in the rest of the filename for you. environment variables Another function of the shell is environment variables. Environment variables are a variable key pair stored in the shell's environment space. This space can be read by any program invoked by the shell, and thus contains a lot of program configuration. Here is a list of common environment variables and what they mean: environment variables Variable Description USER Current logged in user's name. PATH Colon separated list of directories to search for binaries. DISPLAY Network name of the X11 display to connect to, if available. SHELL The current shell. TERM The name of the user's terminal. Used to determine the capabilities of the terminal. TERMCAP Database entry of the terminal escape codes to perform various terminal functions. OSTYPE Type of operating system. e.g., FreeBSD. MACHTYPE The CPU architecture that the system is running on. EDITOR The user's preferred text editor. PAGER The user's preferred text pager. MANPATH Colon separated list of directories to search for manual pages. Bourne shells To view or set an environment variable differs somewhat from shell to shell. For example, in the C-Style shells such as tcsh and csh, you would use setenv to set and view environment variables. Under Bourne shells such as sh and bash, you would use set and export to view and set your current environment variables. For example, to set or modify the EDITOR environment variable, under csh or tcsh a command like this would set EDITOR to /usr/local/bin/emacs: &prompt.user; setenv EDITOR /usr/local/bin/emacs Under Bourne shells: &prompt.user; export EDITOR="/usr/local/bin/emacs" You can also make most shells expand the environment variable by placing a $ character in front of it on the command line. For example, echo $TERM would print out whatever $TERM is set to, because the shell expands $TERM and passes it on to echo. Shells treat a lot of special characters, called meta-characters as special representations of data. The most common one is the * character, which represents any number of characters in a filename. These special meta-characters can be used to do file name globing. For example, typing in echo * is almost the same as typing in ls because the shell takes all the files that match * and puts them on the command line for echo to see. To prevent the shell from interpreting these special characters, they can be escaped from the shell by putting a backslash (\) character in front of them. echo $TERM prints whatever your terminal is set to. echo \$TERM prints $TERM as is. Changing Your Shell The easiest way to change your shell is to use the chsh command. Running chsh will place you into the editor that is in your EDITOR environment variable; if it is not set, you will be placed in vi. Change the Shell: line accordingly. You can also give chsh the option; this will set your shell for you, without requiring you to enter an editor. For example, if you wanted to change your shell to bash, the following should do the trick: &prompt.user; chsh -s /usr/local/bin/bash Running chsh with no parameters and editing the shell from there would work also. The shell that you wish to use must be present in the /etc/shells file. If you have installed a shell from the ports collection, then this should have been done for you already. If you installed the shell by hand, you must do this. For example, if you installed bash by hand and placed it into /usr/local/bin, you would want to: &prompt.root; echo "/usr/local/bin/bash" >> /etc/shells Then rerun chsh. Text Editors text editors editors A lot of configuration in FreeBSD is done by editing text files. Because of this, it would be a good idea to become familiar with a text editor. FreeBSD comes with a few as part of the base system, and many more are available in the ports collection. ee The easiest and simplest editor to learn is an editor called ee, which stands for easy editor. To start ee, one would type at the command line ee filename where filename is the name of the file to be edited. For example, to edit /etc/rc.conf, type in ee /etc/rc.conf. Once inside of ee, all of the commands for manipulating the editor's functions are listed at the top of the display. The caret ^ character means the control key on the keyboard, so ^e expands to pressing the control key plus the letter e. To leave ee, hit the escape key, then choose leave editor. The editor will prompt you to save any changes if the file has been modified. vi editors vi emacs editors emacs FreeBSD also comes with more powerful text editors such as vi as part of the base system, and emacs and vim as part of the FreeBSD Ports Collection. These editors offer much more functionality and power at the expense of being a little more complicated to learn. However if you plan on doing a lot of text editing, learning a more powerful editor such as vim or emacs will save you much more time in the long run. Devices and Device Nodes A device is a term used mostly for hardware-related activities in a system, including disks, printers, graphics cards, and keyboards. When FreeBSD boots, the majority of what FreeBSD displays are devices being detected. You can look through the boot messages again by viewing /var/run/dmesg.boot. For example, acd0 is the first IDE CDROM drive, while kbd0 represents the keyboard. Most of these devices in a Unix operating system must be accessed through a special file called device nodes, which are located in the /dev directory. Creating Device Nodes When adding a new device to your system, or compiling in support for additional devices, a device driver often-times needs to be created. MAKEDEV Script On systems without DEVFS, device nodes are created using the &man.MAKEDEV.8; script as shown below: &prompt.root; cd /dev &prompt.root; sh MAKEDEV ad1 This example would make the proper device nodes for the second IDE drive when installed. devfs (Device File System) - The device file system, or devfs, provides access to + The device filesystem, or devfs, provides access to kernel's device namespace in the global filesystem namespace. Instead of having to create and modify device nodes, devfs maintains this particular filesystem for you. See the &man.devfs.5; man page for more information. devfs is used by default in FreeBSD 5.0. For More Information... Manual Pages manual pages The most comprehensive documentation on FreeBSD is in the form of manual pages. Nearly every program on the system comes with a short reference manual explaining the basic operation and various arguments. These manuals can be viewed with the man command. Use of the man command is simple: &prompt.user; man command command is the name of the command you wish to learn about. For example, to learn more about ls command type: &prompt.user; man ls The online manual is divided up into numbered sections: User commands. System calls and error numbers. Functions in the C libraries. Device drivers. File formats. Games and other diversions. Miscellaneous information. System maintenance and operation commands. Kernel developers. In some cases, the same topic may appear in more than one section of the online manual. For example, there is a chmod user command and a chmod() system call. In this case, you can tell the man command which one you want by specifying the section: &prompt.user; man 1 chmod This will display the manual page for the user command chmod. References to a particular section of the online manual are traditionally placed in parenthesis in written documentation, so &man.chmod.1; refers to the chmod user command and &man.chmod.2; refers to the system call. This is fine if you know the name of the command and simply wish to know how to use it, but what if you cannot recall the command name? You can use man to search for keywords in the command descriptions by using the switch: &prompt.user; man -k mail With this command you will be presented with a list of commands that have the keyword mail in their descriptions. This is actually functionally equivalent to using the apropos command. So, you are looking at all those fancy commands in /usr/bin but do not have the faintest idea what most of them actually do? Simply do: &prompt.user; cd /usr/bin &prompt.user; man -f * or &prompt.user; cd /usr/bin &prompt.user; whatis * which does the same thing. GNU Info Files Free Software Foundation FreeBSD includes many applications and utilities produced by the Free Software Foundation (FSF). In addition to manual pages, these programs come with more extensive hypertext documents called info files which can be viewed with the info command or, if you installed emacs, the info mode of emacs. To use the &man.info.1; command, simply type: &prompt.user; info For a brief introduction, type h. For a quick command reference, type ?. diff --git a/en_US.ISO8859-1/books/handbook/boot/chapter.sgml b/en_US.ISO8859-1/books/handbook/boot/chapter.sgml index a971305f63..d4d384f656 100644 --- a/en_US.ISO8859-1/books/handbook/boot/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/boot/chapter.sgml @@ -1,690 +1,690 @@ The FreeBSD Booting Process Synopsis booting bootstrap The process of starting a computer and loading the operating system is referred to as the bootstrap process, or simply booting. FreeBSD's boot process provides a great deal of flexibility in customizing what happens when you start the system, allowing you to select from different operating systems installed on the same computer, or even different versions of the same operating system or installed kernel. This chapter details the configuration options you can set and how to customize the FreeBSD boot process. This includes everything that happens until the FreeBSD kernel has started, probed for devices, and started &man.init.8;. If you are not quite sure when this happens, it occurs when the text color changes from bright white to grey. After reading this chapter, you will know: What the components of the FreeBSD bootstrap system are, and how they interact. The options you can give to the components in the FreeBSD bootstrap to control the boot process. x86 only This chapter only describes the boot process for FreeBSD running on Intel x86 systems. The Booting Problem Turning on a computer and starting the operating system poses an interesting dilemma. By definition, the computer does not know how to do anything until the operating system is started. This includes running programs from the disk. So if the computer can not run a program from the disk without the operating system, and the operating system programs are on the disk, how is the operating system started? This problem parallels one in the book The Adventures of Baron Munchausen. A character had fallen part way down a manhole, and pulled himself out by grabbing his bootstraps, and lifting. In the early days of computing the term bootstrap was applied to the mechanism used to load the operating system, which has become shortened to booting. On x86 hardware the Basic Input/Output System (BIOS) is responsible for loading the operating system. To do this, the BIOS looks on the hard disk for the Master Boot Record (MBR), which must be located on a specific place on the disk. The BIOS has enough knowledge to load and run the MBR, and assumes that the MBR can then carry out the rest of the tasks involved in loading the operating system. BIOS Basic Input/Output System If you only have one operating system installed on your disks then the standard MBR will suffice. This MBR searches for the first bootable slice on the disk, and then runs the code on that slice to load the remainder of the operating system. If you have installed multiple operating systems on your disks then you can install a different MBR, one that can display a list of different operating systems, and allows you to choose the one to boot from. FreeBSD comes with one such MBR which can be installed, and other operating system vendors also provide alternative MBRs. The remainder of the FreeBSD bootstrap system is divided into three stages. The first stage is run by the MBR, which knows just enough to get the computer into a specific state and run the second stage. The second stage can do a little bit more, before running the third stage. The third stage finishes the task of loading the operating system. The work is split into these three stages because the PC standards put limits on the size of the programs that can be run at stages one and two. Chaining the tasks together allows FreeBSD to provide a more flexible loader. kernel init The kernel is then started and it begins to probe for devices and initialize them for use. Once the kernel boot process is finished, the kernel passes control to the user process &man.init.8;, which then makes sure the disks are in a usable state. &man.init.8; then starts the user-level resource configuration which mounts filesystems, sets up network cards to communicate on the network, and generally starts all the processes that usually are run on a FreeBSD system at startup. The MBR, and Boot Stages One, Two, and Three MBR, <filename>/boot/boot0</filename> Master Boot Record (MBR) The FreeBSD MBR is located in /boot/boot0. This is a copy of the MBR, as the real MBR must be placed on a special part of the disk, outside the FreeBSD area. boot0 is very simple, since the program in the MBR can only be 512 bytes in size. If you have installed the FreeBSD MBR and have installed multiple operating systems on your hard disks then you will see a display similar to this one at boot time. <filename>boot0</filename> Screenshot F1 DOS F2 FreeBSD F3 Linux F4 ?? F5 Drive 1 Default: F2 Other operating systems, in particular Windows 95, have been known to overwrite an existing MBR with their own. If this happens to you, or you want to replace your existing MBR with the FreeBSD MBR then use the following command. &prompt.root; fdisk -B -b /boot/boot0 device Where device is the device that you boot from, such as ad0 for the first IDE disk, ad2 for the first IDE disk on a second IDE controller, da0 for the first SCSI disk, and so on. If you are a Linux user, however, and prefer that LILO control the boot process, you can edit the /etc/lilo.conf file for FreeBSD, or select during the FreeBSD installation process. If you have installed the the FreeBSD boot manager, you can boot back into Linux and modify the LILO configuration file /etc/lilo.conf and add the following option: other=/dev/hdXY table=/dev/hdb loader=/boot/chain.b label=FreeBSD which will permit the booting of FreeBSD and Linux via LILO. In our example, we use XY to determine drive number and partition. If you are using a SCSI drive, you will want to change /dev/hdXY to read something similar to /dev/sdXY, which again uses the XY syntax. The can be omitted if you have both operating systems on the same drive. You can now run /sbin/lilo -v to commit your new changes to the system, this should be verified with screen messages. Stage One, <filename>/boot/boot1</filename>, and Stage Two, <filename>/boot/boot2</filename> Conceptually the first and second stages are part of the same program, on the same area of the disk. Because of space constraints they have been split into two, but you would always install them together. They are found on the boot sector of the boot slice, which is where boot0, or any other program on the MBR expects to find the program to run to continue the boot process. The files in the /boot directory are copies of the real files, which are stored outside of the FreeBSD filesystem. boot1 is very simple, since it too can only be 512 bytes in size, and knows just enough about the FreeBSD disklabel, which stores information about the slice, to find and execute boot2. boot2 is slightly more sophisticated, and understands the FreeBSD filesystem enough to find files on it, and can provide a simple interface to choose the kernel or loader to run. Since the loader is much more sophisticated, and provides a nice easy-to-use boot configuration, boot2 usually runs it, but previously it was tasked to run the kernel directly. <filename>boot2</filename> Screenshot >> FreeBSD/i386 BOOT Default: 0:ad(0,a)/kernel boot: If you ever need to replace the installed boot1 and boot2 use &man.disklabel.8;. &prompt.root; disklabel -B diskslice Where diskslice is the disk and slice you boot from, such as ad0s1 for the first slice on the first IDE disk. Dangerously Dedicated Mode If you use just the disk name, such as ad0, in the &man.disklabel.8; command you will create a dangerously dedicated disk, without slices. This is almost certainly not what you want to do, so make sure you double check the &man.disklabel.8; command before you press Return. Stage Three, <filename>/boot/loader</filename> boot-loader The loader is the final stage of the three-stage bootstrap, and is located on the filesystem, usually as /boot/loader. The loader is intended as a user-friendly method for configuration, using an easy-to-use built-in command set, backed up by a more powerful interpreter, with a more complex command set. Loader Program Flow During initialization, the loader will probe for a console and for disks, and figure out what disk it is booting from. It will set variables accordingly, and an interpreter is started where user commands can be passed from a script or interactively. loader loader configuration The loader will then read /boot/loader.rc, which by default reads in /boot/defaults/loader.conf which sets reasonable defaults for variables and reads /boot/loader.conf for local changes to those variables. loader.rc then acts on these variables, loading whichever modules and kernel are selected. Finally, by default, the loader issues a 10 second wait for key presses, and boots the kernel if it is not interrupted. If interrupted, the user is presented with a prompt which understands the easy-to-use command set, where the user may adjust variables, unload all modules, load modules, and then finally boot or reboot. Loader Built-In Commands These are the most commonly used loader commands. For a complete discussion of all available commands, please see &man.loader.8; autoboot seconds Proceeds to boot the kernel if not interrupted within the time span given, in seconds. It displays a countdown, and the default time span is 10 seconds. boot -options kernelname Immediately proceeds to boot the kernel, with the given options, if any, and with the kernel name given, if it is. boot-conf Goes through the same automatic configuration of modules based on variables as what happens at boot. This only makes sense if you use unload first, and change some variables, most commonly kernel. help topic Shows help messages read from /boot/loader.help. If the topic given is index, then the list of available topics is given. include filename … Processes the file with the given filename. The file is read in, and interpreted line by line. An error immediately stops the include command. load type filename Loads the kernel, kernel module, or file of the type given, with the filename given. Any arguments after filename are passed to the file. ls path Displays a listing of files in the given path, or the root directory, if the path is not specified. If is specified, file sizes will be shown too. lsdev Lists all of the devices from which it may be possible to load modules. If is specified, more details are printed. lsmod Displays loaded modules. If is specified, more details are shown. more filename Displays the files specified, with a pause at each LINES displayed. reboot Immediately reboots the system. set variable set variable=value Sets the loader's environment variables. unload Removes all loaded modules. Loader Examples Here are some practical examples of loader usage. single-user mode To simply boot your usual kernel, but in single-user mode: boot -s To unload your usual kernel and modules, and then load just your old (or another) kernel: kernel.old unload load kernel.old You can use kernel.GENERIC to refer to the generic kernel that comes on the install disk, or kernel.old to refer to your previously installed kernel (when you have upgraded or configured your own kernel, for example). Use the following to load your usual modules with another kernel: unload set kernel="kernel.old" boot-conf To load a kernel configuration script (an automated script which does the things you would normally do in the kernel boot-time configurator): load -t userconfig_script /boot/kernel.conf Kernel Interaction During Boot kernel boot interaction Once the kernel is loaded by either loader (as usual) or boot2 (bypassing the loader), it examines its boot flags, if any, and adjusts its behavior as necessary. kernel bootflags Kernel Boot Flags Here are the more common boot flags: during kernel initialization, ask for the device - to mount as the root file system. + to mount as the root filesystem. boot from CDROM. run UserConfig, the boot-time kernel configurator boot into single-user mode be more verbose during kernel startup There are other boot flags, read &man.boot.8; for more information on them. init Init: Process Control Initialization Once the kernel has finished booting, it passes control to the user process init, which is located at /sbin/init, or the program path specified in the init_path variable in loader. Automatic Reboot Sequence The automatic reboot sequence makes sure that the filesystems available on the system are consistent. If they are not, and fsck cannot fix the inconsistencies, init drops the system into single-user mode for the system administrator to take care of the problems directly. Single-User Mode single-user mode console This mode can be reached through the automatic reboot sequence, or by the user booting with the option or setting the boot_single variable in loader. It can also be reached by calling shutdown without the reboot () or halt () options, from multi-user mode. If the system console is set to insecure in /etc/ttys, then the system prompts for the root password before initiating single-user mode. An Insecure Console in /etc/ttys # name getty type status comments # # If console is marked "insecure", then init will ask for the root password # when going to single-user mode. console none unknown off insecure An insecure console means that you consider your physical security to the console to be insecure, and want to make sure only someone who knows the root password may use single-user mode, and it does not mean that you want to run your console insecurely. Thus, if you want security, choose insecure, not secure. Multi-User Mode multi-user mode If init finds your filesystems to be in order, or once the user has finished in single-user mode, the system enters multi-user mode, in which it starts the resource configuration of the system. rc files Resource Configuration (rc) The resource configuration system reads in configuration defaults from /etc/defaults/rc.conf, and system-specific details from /etc/rc.conf, and then proceeds to mount the system filesystems mentioned in /etc/fstab, start up networking services, start up miscellaneous system daemons, and finally runs the startup scripts of locally installed packages. The &man.rc.8; manual page is a good reference to the resource configuration system, as is examining the scripts themselves. Shutdown Sequence shutdown Upon controlled shutdown, via shutdown, init will attempt to run the script /etc/rc.shutdown, and then proceed to send all processes the TERM signal, and subsequently the KILL signal to any that do not terminate timely. diff --git a/en_US.ISO8859-1/books/handbook/config/chapter.sgml b/en_US.ISO8859-1/books/handbook/config/chapter.sgml index 38e1318126..e57b1a5b8d 100644 --- a/en_US.ISO8859-1/books/handbook/config/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/config/chapter.sgml @@ -1,1228 +1,1228 @@ Chern Lee Written by Mike Smith Based on a tutorial written by Matt Dillon Also based on tuning(7) written by Configuration and Tuning Synopsis system configuration/optimization Configuring a system correctly can substantially reduce the amount of work involved in maintaining and upgrading it in the future. This chapter describes some of the aspects of administrative configuration of FreeBSD systems. This chapter will also describe some of the parameters that can be set to tune a FreeBSD system for optimum performance. After reading this chapter, you will know: Why and how to efficiently size, layout, and place filesystems and swap partitions on your hard drive. The basics of the rc.conf configuration and /usr/local/etc/rc.d startup systems. How to configure virtual hosts on your network devices. How to use the various configuration files in /etc. How to tune FreeBSD using sysctl variables. How to tune disk performance and modify kernel limitations. Before reading this chapter, you should: Understand the basics of Unix and FreeBSD (). Be familiar with keeping FreeBSD sources up to date (), and the basics of kernel configuration/compilation (). Initial Configuration Partition Layout Partition layout /etc /var /usr Base Partitions When laying out your filesystem with &man.disklabel.8; or &man.sysinstall.8;, it is important to remember that hard drives can transfer data at a faster rate from the outer tracks than the inner. Knowing this, you should place your smaller, heavily-accessed filesystems, such as root and swap, closer to the outside of the drive, while placing larger partitions, such as /usr, towards the inner. To do so, it is a good idea to create partitions in a similar order: root, swap, /var, /usr. The size of your /var partition reflects the intended use of your machine. /var is primarily used to hold mailboxes, log files, and printer spools. Mailboxes and log files, in particular, can grow to unexpected sizes based upon how many users are on your system and how long your log files are kept. If you intend to run a mail server, a /var partition of over a gigabyte can be suitable. Additionally, /var/tmp must be large enough to contain any packages you may wish to add. The /usr partition holds the bulk of the files required to support the system and a subdirectory within it called /usr/local holds the bulk of the files installed from the &man.ports.7; hierarchy. If you do not use ports all that much and do not intend to keep system source (/usr/src) on the machine, you can get away with a 1 gigabyte /usr partition. However, if you install a lot of ports (especially window managers and Linux binaries), we recommend at least a two gigabyte /usr and if you also intend to keep system source on the machine, we recommend a three gigabyte /usr. Do not underestimate the amount of space you will need in this partition, it can creep up and surprise you! When sizing your partitions, keep in mind the space requirements for your system to grow. Running out of space in one partition while having plenty in another can lead to much frustration. Some users who have used &man.sysinstall.8;'s Auto-defaults partition sizer have found either their root or /var partitions too small later on. Partition wisely and generously. Swap Partition swap sizing swap partition As a rule of thumb, your swap space should typically be double the amount of main memory. For example, if the machine has 128 megabytes of memory, the swap file should be 256 megabytes. Systems with lesser memory may perform better with a lot more swap. It is not recommended that you configure any less than 256 megabytes of swap on a system and you should keep in mind future memory expansion when sizing the swap partition. The kernel's VM paging algorithms are tuned to perform best when the swap partition is at least two times the size of main memory. Configuring too little swap can lead to inefficiencies in the VM page scanning code as well as create issues later on if you add more memory to your machine. Finally, on larger systems with multiple SCSI disks (or multiple IDE disks operating on different controllers), it is strongly recommend that you configure swap on each drive (up to four drives). The swap partitions on the drives should be approximately the same size. The kernel can handle arbitrary sizes but internal data structures scale to 4 times the largest swap partition. Keeping the swap partitions near the same size will allow the kernel to optimally stripe swap space across the disks. Do not worry about overdoing it a little, swap space is the saving grace of Unix. Even if you do not normally use much swap, it can give you more time to recover from a runaway program before being forced to reboot. Why Partition? Why partition at all? Why not create one big root partition and be done with it? Then I do not have to worry about undersizing things! There are several reasons this is not a good idea. First, each partition has different operational characteristics and separating them allows the filesystem to tune itself to those characteristics. For example, the root and /usr partitions are read-mostly, with very little writing, while a lot of reading and writing could occur in /var and /var/tmp. By properly partitioning your system, fragmentation introduced in the smaller more heavily write-loaded partitions will not bleed over into the mostly-read partitions. Additionally, keeping the write-loaded partitions closer to the edge of the disk, for example before the really big partition instead of after in the partition table, will increase I/O performance in the partitions where you need it the most. Now it is true that you might also need I/O performance in the larger partitions, but they are so large that shifting them more towards the edge of the disk will not lead to a significant performance improvement whereas moving /var to the edge can have a huge impact. Finally, there are safety concerns. Having a small, neat root partition that is essentially read-only gives it a greater chance of surviving a bad crash intact. Core Configuration rc files rc.conf The principal location for system configuration information is within /etc/rc.conf. This file contains a wide range of configuration information, principally used at system startup to configure the system. Its name directly implies this; it is configuration information for the rc* files. An administrator should make entries in the rc.conf file to override the default settings from /etc/defaults/rc.conf. The defaults file should not be copied verbatim to /etc - it contains default values, not examples. All system-specific changes should be made in the rc.conf file itself. A number of strategies may be applied in clustered applications to separate site-wide configuration from system-specific configuration in order to keep administration overhead down. The recommended approach is to place site-wide configuration into another file, such as /etc/rc.conf.site, and then include this file into /etc/rc.conf, which will contain only system-specific information. As rc.conf is read by &man.sh.1; it is trivial to achieve this. For example: rc.conf: . rc.conf.site hostname="node15.example.com" network_interfaces="fxp0 lo0" ifconfig_fxp0="inet 10.1.1.1" rc.conf.site: defaultrouter="10.1.1.254" saver="daemon" blanktime="100" The rc.conf.site file can then be distributed to every system using rsync or a similar program, while the rc.conf file remains unique. Upgrading the system using &man.sysinstall.8; or make world will not overwrite the rc.conf file, so system configuration information will not be lost. Application Configuration Typically, installed applications have their own configuration files, with their own syntax, etc. It is important that these files be kept separate from the base system, so that they may be easily located and managed by the package management tools. /usr/local/etc Typically, these files are installed in /usr/local/etc. In the case where an application has a large number of configuration files, a subdirectory will be created to hold them. Normally, when a port or package is installed, sample configuration files are also installed. These are usually identified with a .default suffix. If there are no existing configuration files for the application, they will be created by copying the .default files. For example, consider the contents of the directory /usr/local/etc/apache: -rw-r--r-- 1 root wheel 2184 May 20 1998 access.conf -rw-r--r-- 1 root wheel 2184 May 20 1998 access.conf.default -rw-r--r-- 1 root wheel 9555 May 20 1998 httpd.conf -rw-r--r-- 1 root wheel 9555 May 20 1998 httpd.conf.default -rw-r--r-- 1 root wheel 12205 May 20 1998 magic -rw-r--r-- 1 root wheel 12205 May 20 1998 magic.default -rw-r--r-- 1 root wheel 2700 May 20 1998 mime.types -rw-r--r-- 1 root wheel 2700 May 20 1998 mime.types.default -rw-r--r-- 1 root wheel 7980 May 20 1998 srm.conf -rw-r--r-- 1 root wheel 7933 May 20 1998 srm.conf.default The filesize difference shows that only the srm.conf file has been changed. A later update of the apache port would not overwrite this changed file. Starting Services services It is common for a system to host a number of services. These may be started in several different fashions, each having different advantages. /usr/local/etc/rc.d Software installed from a port or the packages collection will often place a script in /usr/local/etc/rc.d which is invoked at system startup with a argument, and at system shutdown with a argument. This is the recommended way for starting system-wide services that are to be run as root, or that expect to be started as root. These scripts are registered as part of the installation of the package, and will be removed when the package is removed. A generic startup script in /usr/local/etc/rc.d looks like: #!/bin/sh echo -n ' FooBar' case "$1" in start) /usr/local/bin/foobar ;; stop) kill -9 `cat /var/run/foobar.pid` ;; *) echo "Usage: `basename $0` {start|stop}" >&2 exit 64 ;; esac exit 0 The startup scripts of FreeBSD will look in /usr/local/etc/rc.d for scripts that have an .sh extension and are executable by root. Those scripts that are found are called with an option at startup, and at shutdown to allow them to carry out their purpose. So if you wanted the above sample script to be picked up and run at the proper time during system startup, you should save it to a file called FooBar.sh in /usr/local/etc/rc.d and make sure it's executable. You can make a shell script executable with &man.chmod.1; as shown below: &prompt.root; chmod 755 FooBar.sh Some services expect to be invoked by &man.inetd.8; when a connection is received on a suitable port. This is common for mail reader servers (POP and IMAP, etc.). These services are enabled by editing the file /etc/inetd.conf. See &man.inetd.8; for details on editing this file. Some additional system services may not be covered by the toggles in /etc/rc.conf. These are traditionally enabled by placing the command(s) to invoke them in /etc/rc.local. As of FreeBSD 3.1 there is no default /etc/rc.local; if it is created by the administrator it will however be honored in the normal fashion. Note that rc.local is generally regarded as the location of last resort; if there is a better place to start a service, do it there. Do not place any commands in /etc/rc.conf. To start daemons, or run any commands at boot time, place a script in /usr/local/etc/rc.d instead. It is also possible to use the &man.cron.8; daemon to start system services. This approach has a number of advantages, not least being that because &man.cron.8; runs these processes as the owner of the crontab, services may be started and maintained by non-root users. This takes advantage of a feature of &man.cron.8;: the time specification may be replaced by @reboot, which will cause the job to be run when &man.cron.8; is started shortly after system boot. Virtual Hosts virtual hosts ip aliases A very common use of FreeBSD is virtual site hosting, where one server appears to the network as many servers. This is achieved by assigning multiple network addresses to a single interface. A given network interface has one real address, and may have any number of alias addresses. These aliases are normally added by placing alias entries in /etc/rc.conf. An alias entry for the interface fxp0 looks like: ifconfig_fxp0_alias0="inet xxx.xxx.xxx.xxx netmask xxx.xxx.xxx.xxx" Note that alias entries must start with alias0 and proceed upwards in order, (for example, _alias1, _alias2, and so on). The configuration process will stop at the first missing number. The calculation of alias netmasks is important, but fortunately quite simple. For a given interface, there must be one address which correctly represents the network's netmask. Any other addresses which fall within this network must have a netmask of all 1's. For example, consider the case where the fxp0 interface is connected to two networks, the 10.1.1.0 network with a netmask of 255.255.255.0 and the 202.0.75.16 network with a netmask of 255.255.255.240. We want the system to appear at 10.1.1.1 through 10.1.1.5 and at 202.0.75.17 through 202.0.75.20. The following entries configure the adapter correctly for this arrangement: ifconfig_fxp0="inet 10.1.1.1 netmask 255.255.255.0" ifconfig_fxp0_alias0="inet 10.1.1.2 netmask 255.255.255.255" ifconfig_fxp0_alias1="inet 10.1.1.3 netmask 255.255.255.255" ifconfig_fxp0_alias2="inet 10.1.1.4 netmask 255.255.255.255" ifconfig_fxp0_alias3="inet 10.1.1.5 netmask 255.255.255.255" ifconfig_fxp0_alias4="inet 202.0.75.17 netmask 255.255.255.240" ifconfig_fxp0_alias5="inet 202.0.75.18 netmask 255.255.255.255" ifconfig_fxp0_alias6="inet 202.0.75.19 netmask 255.255.255.255" ifconfig_fxp0_alias7="inet 202.0.75.20 netmask 255.255.255.255" Configuration Files <filename>/etc</filename> Layout There are a number of directories in which configuration information is kept. These include: /etc Generic system configuration information; data here is system-specific. /etc/defaults Default versions of system configuration files. /etc/mail Extra &man.sendmail.8; configuration, other MTA configuration files. /etc/ppp Configuration for both user- and kernel-ppp programs. /etc/namedb Default location for &man.named.8; data. Normally the boot file is located here, and contains a directive to refer to other data in /var/db. /usr/local/etc Configuration files for installed applications. May contain per-application subdirectories. /usr/local/etc/rc.d Start/stop scripts for installed applications. /var/db Persistent system-specific data files, such as &man.named.8; zone files, database files, and so on. Hostnames hostname DNS <filename>/etc/resolv.conf</filename> resolv.conf /etc/resolv.conf dictates how FreeBSD's resolver accesses the Internet Domain Name System (DNS). The most common entries to resolv.conf are: nameserver The IP address of a name server the resolver should query. The servers are queried in the order listed with a maximum of three. search Search list for hostname lookup. This is normally determined by the domain of the local hostname. domain The local domain name. A typical resolv.conf: search example.com nameserver 147.11.1.11 nameserver 147.11.100.30 Only one of the search and domain options should be used. If you are using DHCP, &man.dhclient.8; usually rewrites resolv.conf with information received from the DHCP server. <filename>/etc/hosts</filename> hosts /etc/hosts is a simple text database reminiscent of the old Internet. It works in conjunction with DNS and NIS providing name to IP address mappings. Local computers connected via a LAN can be placed in here for simplistic naming purposes instead of setting up a &man.named.8; server. Additionally, /etc/hosts can be used to provide a local record of Internet names, reducing the need to query externally for commonly accessed names. # $FreeBSD$ # # Host Database # This file should contain the addresses and aliases # for local hosts that share this file. # In the presence of the domain name service or NIS, this file may # not be consulted at all; see /etc/nsswitch.conf for the resolution order. # # ::1 localhost localhost.my.domain myname.my.domain 127.0.0.1 localhost localhost.my.domain myname.my.domain # # Imaginary network. #10.0.0.2 myname.my.domain myname #10.0.0.3 myfriend.my.domain myfriend # # According to RFC 1918, you can use the following IP networks for # private nets which will never be connected to the Internet: # # 10.0.0.0 - 10.255.255.255 # 172.16.0.0 - 172.31.255.255 # 192.168.0.0 - 192.168.255.255 # # In case you want to be able to connect to the Internet, you need # real official assigned numbers. PLEASE PLEASE PLEASE do not try # to invent your own network numbers but instead get one from your # network provider (if any) or from the Internet Registry (ftp to # rs.internic.net, directory `/templates'). # /etc/hosts takes on the simple format of: [Internet address] [official hostname] [alias1] [alias2] ... For example: 10.0.0.1 myRealHostname.example.com myRealHostname foobar1 foobar2 Consult &man.hosts.5; for more information. Log File Configuration log files <filename>syslog.conf</filename> syslog.conf syslog.conf is the configuration file for the &man.syslogd.8; program. It indicates which types of syslog messages are logged to particular log files. # $FreeBSD$ # # Spaces ARE valid field separators in this file. However, # other *nix-like systems still insist on using tabs as field # separators. If you are sharing this file between systems, you # may want to use only tabs as field separators here. # Consult the syslog.conf(5) manual page. *.err;kern.debug;auth.notice;mail.crit /dev/console *.notice;kern.debug;lpr.info;mail.crit;news.err /var/log/messages security.* /var/log/security mail.info /var/log/maillog lpr.info /var/log/lpd-errs cron.* /var/log/cron *.err root *.notice;news.err root *.alert root *.emerg * # uncomment this to log all writes to /dev/console to /var/log/console.log #console.info /var/log/console.log # uncomment this to enable logging of all log messages to /var/log/all.log #*.* /var/log/all.log # uncomment this to enable logging to a remote log host named loghost #*.* @loghost # uncomment these if you're running inn # news.crit /var/log/news/news.crit # news.err /var/log/news/news.err # news.notice /var/log/news/news.notice !startslip *.* /var/log/slip.log !ppp *.* /var/log/ppp.log Consult the &man.syslog.conf.5; manual page for more information. <filename>newsyslog.conf</filename> newsyslog.conf newsyslog.conf is the configuration file for &man.newsyslog.8;, a program that is normally scheduled to run by &man.cron.8;. &man.newsyslog.8; determines when log files require archiving or rearranging. logfile is moved to logfile.0, logfile.0 is moved to logfile.1, and so on. Alternatively, the log files may be archived in &man.gzip.1; format causing them to be named: logfile.0.gz, logfile.1.gz, and so on. newsyslog.conf indicates which log files are to be managed, how many are to be kept, and when they are to be touched. Log files can be rearranged and/or archived when they have either reached a certain size, or at a certain periodic time/date. # configuration file for newsyslog # $FreeBSD$ # # filename [owner:group] mode count size when [ZB] [/pid_file] [sig_num] /var/log/cron 600 3 100 * Z /var/log/amd.log 644 7 100 * Z /var/log/kerberos.log 644 7 100 * Z /var/log/lpd-errs 644 7 100 * Z /var/log/maillog 644 7 * @T00 Z /var/log/sendmail.st 644 10 * 168 B /var/log/messages 644 5 100 * Z /var/log/all.log 600 7 * @T00 Z /var/log/slip.log 600 3 100 * Z /var/log/ppp.log 600 3 100 * Z /var/log/security 600 10 100 * Z /var/log/wtmp 644 3 * @01T05 B /var/log/daily.log 640 7 * @T00 Z /var/log/weekly.log 640 5 1 $W6D0 Z /var/log/monthly.log 640 12 * $M1D0 Z /var/log/console.log 640 5 100 * Z Consult the &man.newsyslog.8; manual page for more information. <filename>sysctl.conf</filename> sysctl.conf sysctl sysctl.conf looks much like rc.conf. Values are set in a variable=value form. The specified values are set after the system goes into multi-user mode. Not all variables are settable in this mode. A sample sysctl.conf turning off logging of fatal signal exits and letting Linux programs know they are really running under FreeBSD. kern.logsigexit=0 # Do not log fatal signal exits (e.g. sig 11) compat.linux.osname=FreeBSD compat.linux.osrelease=4.3-STABLE Tuning with sysctl sysctl Tuning with sysctl &man.sysctl.8; is an interface that allows you to make changes to a running FreeBSD system. This includes many advanced options of the TCP/IP stack and virtual memory system that can dramatically improve performance for an experienced system administrator. Over five hundred system variables can be read and set using &man.sysctl.8;. At its core, &man.sysctl.8; serves two functions: to read and to modify system settings. To view all readable variables: &prompt.user; sysctl -a To read a particular variable, for example, kern.maxproc: &prompt.user; sysctl kern.maxproc kern.maxproc: 1044 To set a particular variable, use the intuitive variable=value syntax: &prompt.root; sysctl kern.maxfiles=5000 kern.maxfiles: 2088 -> 5000 Settings of sysctl variables are usually either strings, numbers, or booleans (a boolean being 1 for yes or a 0 for no). Tuning Disks Sysctl Variables <varname>vfs.vmiodirenable</varname> vfs.vmiodirenable The vfs.vmiodirenable sysctl variable may be set to either 0 (off) or 1 (on); it is 1 by default. This variable controls how directories are cached by the system. Most directories are small, using just a single fragment (typically 1K) in the filesystem and less (typically 512 bytes) in the buffer cache. However, when operating in the default mode the buffer cache will only cache a fixed number of directories even if you have a huge amount of memory. Turning on this sysctl allows the buffer cache to use the VM Page Cache to cache the directories, making all the memory available for caching directories. However, the minimum in-core memory used to cache a directory is the physical page size (typically 4K) rather than 512 bytes. We recommend turning this option on if you are running any services which manipulate large numbers of files. Such services can include web caches, large mail systems, and news systems. Turning on this option will generally not reduce performance even with the wasted memory but you should experiment to find out. <varname>hw.ata.wc</varname> hw.ata.wc FreeBSD 4.3 flirted with turning off IDE write caching. This reduced write bandwidth to IDE disks but was considered necessary due to serious data consistency issues introduced by hard drive vendors. The problem is that IDE drives lie about when a write completes. With IDE write caching turned on, IDE hard drives not only write data to disk out of order, but will sometimes delay writing some blocks indefinitely when under heavy disk loads. A crash or power failure may cause serious filesystem corruption. FreeBSD's default was changed to be safe. Unfortunately, the result was such a huge performance loss that we changed write caching back to on by default after the release. You should check the default on your system by observing the hw.ata.wc sysctl variable. If IDE write caching is turned off, you can turn it back on by setting the kernel variable back to 1. This must be done from the boot loader at boot time. Attempting to do it after the kernel boots will have no effect. For more information, please see &man.ata.4;. Soft Updates Soft Updates tunefs The &man.tunefs.8; program can be used to fine-tune a filesystem. This program has many different options, but for now we are only concerned with toggling Soft Updates on and off, which is done by: &prompt.root; tunefs -n enable /filesystem &prompt.root; tunefs -n disable /filesystem A filesystem cannot be modified with &man.tunefs.8; while it is mounted. A good time to enable Soft Updates is before any partitions have been mounted, in single-user mode. As of FreeBSD 4.5, it is possible to enable Soft Updates at filesystem creation time, through use of the -U option to &man.newfs.8;. Soft Updates drastically improves meta-data performance, mainly file creation and deletion, through the use of a memory cache. We recommend turning Soft Updates on on all of your filesystems. There are two downsides to Soft Updates that you should be aware of: First, Soft Updates guarantees filesystem consistency in the case of a crash but could very easily be several seconds (even a minute!) behind updating the physical disk. If your system crashes you may lose more work than otherwise. Secondly, Soft Updates delays the freeing of filesystem blocks. If you have a filesystem (such as the root filesystem) which is almost full, performing a major update, such as make installworld, can cause the filesystem to run out of space and the update to fail. More details about Soft Updates Soft Updates (Details) There are two traditional approaches to writing a filesystem's meta-data back to disk. (Meta-data updates are updates to non-content data like inodes or directories.) Historically, the default behaviour was to write out meta-data updates synchronously. If a directory had been changed, the system waited until the change was actually written to disk. The file data buffers (file contents) were passed through the buffer cache and backed up to disk later on asynchronously. The advantage of this implementation is that it operates safely. If there is a failure during an update, the meta-data are always in a consistent state. A file is either created completely or not at all. If the data blocks of a file did not find their way out of the buffer cache onto the disk by the time of the crash, &man.fsck.8; is able to recognize this and repair the filesystem by setting the file length to 0. Additionally, the implementation is clear and simple. The disadvantage is that meta-data changes are slow. An rm -r, for instance, touches all the files in a directory sequentially, but each directory change (deletion of a file) will be written synchronously to the disk. This includes updates to the directory itself, to the inode table, and possibly to indirect blocks allocated by the file. Similar considerations apply for unrolling large hierarchies (tar -x). The second case is asynchronous meta-data updates. This is the default for Linux/ext2fs and mount -o async for *BSD ufs. All meta-data updates are simply being passed through the buffer cache too, that is, they will be intermixed with the updates of the file content data. The advantage of this implementation is there is no need to wait until each meta-data update has been written to disk, so all operations which cause huge amounts of meta-data updates work much faster than in the synchronous case. Also, the implementation is still clear and simple, so there is a low risk for bugs creeping into the code. The disadvantage is that there is no guarantee at all for a consistent state of the filesystem. If there is a failure during an operation that updated large amounts of meta-data (like a power failure, or someone pressing the reset button), - the file system + the filesystem will be left in an unpredictable state. There is no opportunity - to examine the state of the file system when the system + to examine the state of the filesystem when the system comes up again; the data blocks of a file could already have been written to the disk while the updates of the inode table or the associated directory were not. It is actually impossible to implement a fsck which is able to clean up the resulting chaos (because the necessary information is not available on the disk). If the filesystem has been damaged beyond repair, the only choice is to newfs it and restore it from backup. The usual solution for this problem was to implement dirty region logging, which is also referred to as journaling, although that term is not used consistently and is occasionally applied to other forms of transaction logging as well. Meta-data updates are still written synchronously, but only into a small region of the disk. Later on they will be moved to their proper location. Because the logging area is a small, contiguous region on the disk, there are no long distances for the disk heads to move, even during heavy operations, so these operations are quicker than synchronous updates. Additionally the complexity of the implementation is fairly limited, so the risk of bugs being present is low. A disadvantage is that all meta-data are written twice (once into the logging region and once to the proper location) so for normal work, a performance pessimization might result. On the other hand, in case of a crash, all pending meta-data operations can be quickly either rolled-back or completed from the logging area after the system comes up again, resulting in a fast filesystem startup. Kirk McKusick, the developer of Berkeley FFS, solved this problem with Soft Updates: all pending meta-data updates are kept in memory and written out to disk in a sorted sequence (ordered meta-data updates). This has the effect that, in case of heavy meta-data operations, later updates to an item catch the earlier ones if the earlier ones are still in memory and have not already been written to disk. So all operations on, say, a directory are generally performed in memory before the update is written to disk (the data blocks are sorted according to their position so that they will not be on the disk ahead of their meta-data). If the system crashes, this causes an implicit log rewind: all operations which did not find their way to the disk appear as if they had never happened. A consistent filesystem state is maintained that appears to be the one of 30 to 60 seconds earlier. The algorithm used guarantees that all resources in use are marked as such in their appropriate bitmaps: blocks and inodes. After a crash, the only resource allocation error that occurs is that resources are marked as used which are actually free. &man.fsck.8; recognizes this situation, and frees the resources that are no longer used. It is safe to ignore the dirty state of the filesystem after a crash by forcibly mounting it with mount -f. In order to free resources that may be unused, &man.fsck.8; needs to be run at a later time. This is the idea behind the background fsck: at system startup time, only a snapshot of the filesystem is recorded. The fsck can be run later on. All filesystems can then be mounted dirty, so the system startup proceeds in multiuser mode. Then, background fscks will be scheduled for all filesystems where this is required, to free resources that may be unused. (Filesystems that do not use Soft Updates still need the usual foreground fsck though.) The advantage is that meta-data operations are nearly as fast as asynchronous updates (i.e. faster than with logging, which has to write the meta-data twice). The disadvantages are the complexity of the code (implying a higher risk for bugs in an area that is highly sensitive regarding loss of user data), and a higher memory consumption. Additionally there are some idiosyncrasies one has to get used to. After a crash, the state of the filesystem appears to be somewhat older. In situations where the standard synchronous approach would have caused some zero-length files to remain after the fsck, these files do not exist at all with a Soft Updates filesystem because neither the meta-data nor the file contents have ever been written to disk. Disk space is not released until the updates have been written to disk, which may take place some time after running rm. This may cause problems when installing large amounts of data on a filesystem that does not have enough free space to hold all the files twice. Tuning Kernel Limits Tuning kernel limits File/Process Limits <varname>kern.maxfiles</varname> kern.maxfiles kern.maxfiles can be raised or lowered based upon your system requirements. This variable indicates the maximum number of file descriptors on your system. When the file descriptor table is full, file: table is full will show up repeatedly in the system message buffer, which can be viewed with the dmesg command. Each open file, socket, or fifo uses one file descriptor. A large-scale production server may easily require many thousands of file descriptors, depending on the kind and number of services running concurrently. kern.maxfile's default value is dictated by the option in your kernel configuration file. kern.maxfiles grows proportionally to the value of . When compiling a custom kernel, it is a good idea to set this kernel configuration option according to the uses of your system. From this number, the kernel is given most of its pre-defined limits. Even though a production machine may not actually have 256 users connected as once, the resources needed may be similar to a high-scale web server. As of FreeBSD 4.5, setting to 0 in your kernel configuration file will choose a reasonable default value based on the amount of RAM present in your system. Network Limits The kernel configuration option dictates the amount of network mbufs available to the system. A heavily-trafficked server with a low number of MBUFs will hinder FreeBSD's ability. Each cluster represents approximately 2K of memory, so a value of 1024 represents 2 megabytes of kernel memory reserved for network buffers. A simple calculation can be done to figure out how many are needed. If you have a web server which maxes out at 1000 simultaneous connections, and each connection eats a 16K receive and 16K send buffer, you need approximately 32MB worth of network buffers to cover the web server. A good rule of thumb is to multiply by 2, so 2x32 MB / 2 KB = 64 MB / 2 kB = 32768. Adding Swap Space No matter how well you plan, sometimes a system doesn't run as you expect. If you find you need more swap space, it's simple enough to add. You have three ways to increase swap space: adding a new hard drive, enabling swap over NFS, and creating a swap file on an existing partition. Swap on a New Hard Drive The best way to add swap, of course, is to use this as an excuse to add another hard drive. You can always use another hard drive, after all. If you can do this, go reread the discussion of swap space from the Initial Configuration section of the Handbook for some suggestions on how to best arrange your swap. Swapping over NFS Swapping over NFS is only recommended if you do not have a local hard disk to swap to. Swapping over NFS is slow and inefficient in versions of FreeBSD prior to 4.x. It is reasonably fast and efficient in 4.0-RELEASE and newer. Even with newer versions of FreeBSD, NFS swapping will be limited by the available network bandwidth and puts an additional burden on the NFS server. Swapfiles You can create a file of a specified size to use as a swap file. In our example here we will use a 64Mb file called /usr/swap0. You can use any name you want, of course. Creating a Swapfile Be certain that your kernel configuration includes the vnode driver. It is not in recent versions of GENERIC. pseudo-device vn 1 #Vnode driver (turns a file into a device) create a vn-device: &prompt.root; cd /dev &prompt.root; sh MAKEDEV vn0 create a swapfile (/usr/swap0): &prompt.root; dd if=/dev/zero of=/usr/swap0 bs=1024k count=64 set proper permissions on (/usr/swap0): &prompt.root; chmod 0600 /usr/swap0 enable the swap file in /etc/rc.conf: swapfile="/usr/swap0" # Set to name of swapfile if aux swapfile desired. Reboot the machine or to enable the swap file immediately, type: &prompt.root; vnconfig -e /dev/vn0b /usr/swap0 swap diff --git a/en_US.ISO8859-1/books/handbook/disks/chapter.sgml b/en_US.ISO8859-1/books/handbook/disks/chapter.sgml index 06e9c99283..a6f8c2d0b9 100644 --- a/en_US.ISO8859-1/books/handbook/disks/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/disks/chapter.sgml @@ -1,2251 +1,2251 @@ Storage Synopsis This chapter covers the use of disks in FreeBSD. This includes memory-backed disks, network-attached disks, and standard SCSI/IDE storage devices. After reading this chapter, you will know: The terminology FreeBSD uses to describe the organization of data on a physical disk (partitions and slices). How to mount and unmount filesystems. How to add additional hard disks to your system. How to setup virtual filesystems, such as memory disks. How to use quotas to limit disk space usage. How to create and burn CDs and DVDs on FreeBSD. The various storage media options for backups. How to use backup programs available under FreeBSD. How to backup to floppy disks. Device Names The following is a list of physical storage devices supported in FreeBSD, and the device names associated with them. Physical Disk Naming Conventions Drive type Drive device name IDE hard drives ad IDE CDROM drives acd SCSI hard drives and USB Mass storage devices da SCSI CDROM drives cd Assorted non-standard CDROM drives mcd for Mitsumi CD-ROM, scd for Sony CD-ROM, matcd for Matsushita/Panasonic CD-ROM Floppy drives fd SCSI tape drives sa IDE tape drives ast Flash drives fla for DiskOnChip Flash device RAID drives myxd for Mylex, and amrd for AMI MegaRAID, idad for Compaq Smart RAID.
David O'Brien Originally contributed by Adding Disks disks adding Lets say we want to add a new SCSI disk to a machine that currently only has a single drive. First turn off the computer and install the drive in the computer following the instructions of the computer, controller, and drive manufacturer. Due to the wide variations of procedures to do this, the details are beyond the scope of this document. Login as user root. After you have installed the drive, inspect /var/run/dmesg.boot to ensure the new disk was found. Continuing with our example, the newly added drive will be da1 and we want to mount it on /1 (if you are adding an IDE drive, the device name will be wd1 in pre-4.0 systems, or ad1 in most 4.X systems). partitions slices fdisk Because FreeBSD runs on IBM-PC compatible computers, it must take into account the PC BIOS partitions. These are different from the traditional BSD partitions. A PC disk has up to four BIOS partition entries. If the disk is going to be truly dedicated to FreeBSD, you can use the dedicated mode. Otherwise, FreeBSD will have to live within one of the PC BIOS partitions. FreeBSD calls the PC BIOS partitions slices so as not to confuse them with traditional BSD partitions. You may also use slices on a disk that is dedicated to FreeBSD, but used in a computer that also has another operating system installed. This is to not confuse the fdisk utility of the other operating system. In the slice case the drive will be added as /dev/da1s1e. This is read as: SCSI disk, unit number 1 (second SCSI disk), slice 1 (PC BIOS partition 1), and e BSD partition. In the dedicated case, the drive will be added simply as /dev/da1e. Using &man.sysinstall.8; sysinstall adding disks su Navigating <application>Sysinstall</application> You may use /stand/sysinstall to partition and label a new disk using its easy to use menus. Either login as user root or use the su command. Run /stand/sysinstall and enter the Configure menu. Within the FreeBSD Configuration Menu, scroll down and select the Fdisk option. <application>fdisk</application> Partition Editor Once inside fdisk, we can type A to use the entire disk for FreeBSD. When asked if you want to remain cooperative with any future possible operating systems, answer YES. Write the changes to the disk using W. Now exit the FDISK editor by typing q. Next you will be asked about the Master Boot Record. Since you are adding a disk to an already running system, choose None. Disk Label Editor BSD partitions Next, you need to exit sysinstall and start it again. Follow the directions above, although this time choose the Label option. This will enter the Disk Label Editor. This is where you will create the traditional BSD partitions. A disk can have up to eight partitions, labeled a-h. A few of the partition labels have special uses. The a partition is used for the root partition (/). Thus only your system disk (e.g, the disk you boot from) should have an a partition. The b partition is used for swap partitions, and you may have many disks with swap partitions. The c partition addresses the entire disk in dedicated mode, or the entire FreeBSD slice in slice mode. The other partitions are for general use. sysinstall's Label editor favors the e partition for non-root, non-swap partitions. Within the - Label editor, create a single file system by typing + Label editor, create a single filesystem by typing C. When prompted if this will be a FS - (file system) or swap, choose FS and type in a + (filesystem) or swap, choose FS and type in a mount point (e.g, /mnt). When adding a disk in post-install mode, sysinstall will not create entries in /etc/fstab for you, so the mount point you specify is not important. You are now ready to write the new label to the disk and - create a file system on it. Do this by typing + create a filesystem on it. Do this by typing W. Ignore any errors from sysinstall that it could not mount the new partition. Exit the Label Editor and sysinstall completely. Finish The last step is to edit /etc/fstab to add an entry for your new disk. Using Command Line Utilities Using Slices This setup will allow your disk to work correctly with other operating systems that might be installed on your computer and will not confuse other operating systems' fdisk utilities. It is recommended to use this method for new disk installs. Only use dedicated mode if you have a good reason to do so! &prompt.root; dd if=/dev/zero of=/dev/rda1 bs=1k count=1 &prompt.root; fdisk -BI da1 #Initialize your new disk &prompt.root; disklabel -B -w -r da1s1 auto #Label it. &prompt.root; disklabel -e da1s1 # Edit the disklabel just created and add any partitions. &prompt.root; mkdir -p /1 &prompt.root; newfs /dev/da1s1e # Repeat this for every partition you created. &prompt.root; mount -t ufs /dev/da1s1e /1 # Mount the partition(s) &prompt.root; vi /etc/fstab # Add the appropriate entry/entries to your /etc/fstab. If you have an IDE disk, substitute ad for da. On pre-4.X systems use wd. Dedicated OS/2 If you will not be sharing the new drive with another operating system, you may use the dedicated mode. Remember this mode can confuse Microsoft operating systems; however, no damage will be done by them. IBM's OS/2 however, will appropriate any partition it finds which it does not understand. &prompt.root; dd if=/dev/zero of=/dev/rda1 bs=1k count=1 &prompt.root; disklabel -Brw da1 auto &prompt.root; disklabel -e da1 # create the `e' partition &prompt.root; newfs -d0 /dev/rda1e &prompt.root; mkdir -p /1 &prompt.root; vi /etc/fstab # add an entry for /dev/da1e &prompt.root; mount /1 An alternate method is: &prompt.root; dd if=/dev/zero of=/dev/rda1 count=2 &prompt.root; disklabel /dev/rda1 | disklabel -BrR da1 /dev/stdin &prompt.root; newfs /dev/rda1e &prompt.root; mkdir -p /1 &prompt.root; vi /etc/fstab # add an entry for /dev/da1e &prompt.root; mount /1 Network, Memory, and File-Based Filesystems virtual disks disks virtual Aside from the disks you physically insert into your computer: floppies, CDs, hard drives, and so forth; other forms of disks are understood by FreeBSD - the virtual disks. NFS Coda disks memory These include network filesystems such as the Network Filesystem and Coda, memory-based filesystems such as md and file-backed filesystems created by vnconfig or mdconfig. vnconfig: File-Backed Filesystem disks file-backed &man.vnconfig.8; configures and enables vnode pseudo-disk devices. A vnode is a representation of a file, and is the focus of file activity. This means that &man.vnconfig.8; uses files to create and operate a filesystem. One possible use is the mounting of floppy or CD images kept in files. To mount an existing filesystem image: Using vnconfig to mount an Existing Filesystem Image &prompt.root; vnconfig vn0 diskimage &prompt.root; mount /dev/vn0c /mnt To create a new filesystem image with vnconfig: Creating a New File-Backed Disk with vnconfig &prompt.root; dd if=/dev/zero of=newimage bs=1k count=5k 5120+0 records in 5120+0 records out &prompt.root; vnconfig -s labels -c vn0 newimage &prompt.root; disklabel -r -w vn0 auto &prompt.root; newfs vn0c Warning: 2048 sector(s) in last cylinder unallocated /dev/rvn0c: 10240 sectors in 3 cylinders of 1 tracks, 4096 sectors 5.0MB in 1 cyl groups (16 c/g, 32.00MB/g, 1280 i/g) super-block backups (for fsck -b #) at: 32 &prompt.root; mount /dev/vn0c /mnt &prompt.root; df /mnt Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/vn0c 4927 1 4532 0% /mnt md: Memory Filesystem disks memory filesystem md is a simple, efficient means to create memory filesystems. Simply take a filesystem you have prepared with, for example, &man.vnconfig.8;, and: md Memory Disk &prompt.root; dd if=newimage of=/dev/md0 5120+0 records in 5120+0 records out &prompt.root; mount /dev/md0c /mnt &prompt.root; df /mnt Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/md0c 4927 1 4532 0% /mnt File System Quotas accounting disk space disk quotas Quotas are an optional feature of the operating system that allow you to limit the amount of disk space and/or the number of files a user or members of a group may allocate on a per-file system basis. This is used most often on timesharing systems where it is desirable to limit the amount of resources any one user or group of users may allocate. This will prevent one user or group of users from consuming all of the available disk space. Configuring Your System to Enable Disk Quotas Before attempting to use disk quotas, it is necessary to make sure that quotas are configured in your kernel. This is done by adding the following line to your kernel configuration file: options QUOTA The stock GENERIC kernel does not have this enabled by default, so you will have to configure, build and install a custom kernel in order to use disk quotas. Please refer to for more information on kernel configuration. Next you will need to enable disk quotas in /etc/rc.conf. This is done by adding the line: enable_quotas=YES disk quotas checking For finer control over your quota startup, there is an additional configuration variable available. Normally on bootup, - the quota integrity of each file system is checked by the + the quota integrity of each filesystem is checked by the quotacheck program. The quotacheck facility insures that the data in - the quota database properly reflects the data on the file system. + the quota database properly reflects the data on the filesystem. This is a very time consuming process that will significantly affect the time your system takes to boot. If you would like to skip this step, a variable in /etc/rc.conf is made available for the purpose: check_quotas=NO If you are running FreeBSD prior to 3.2-RELEASE, the configuration is simpler, and consists of only one variable. Set the following in your /etc/rc.conf: check_quotas=YES Finally you will need to edit /etc/fstab - to enable disk quotas on a per-file system basis. This is where + to enable disk quotas on a per-filesystem basis. This is where you can either enable user or group quotas or both for all of your - file systems. + filesystems. - To enable per-user quotas on a file system, add the + To enable per-user quotas on a filesystem, add the userquota option to the options field in the - /etc/fstab entry for the file system you want + /etc/fstab entry for the filesystem you want to enable quotas on. For example: /dev/da1s2g /home ufs rw,userquota 1 2 Similarly, to enable group quotas, use the groupquota option instead of userquota. To enable both user and group quotas, change the entry as follows: /dev/da1s2g /home ufs rw,userquota,groupquota 1 2 By default, the quota files are stored in the root directory of - the file system with the names quota.user and + the filesystem with the names quota.user and quota.group for user and group quotas respectively. See &man.fstab.5; for more information. Even though the &man.fstab.5; manual page says that you can specify an alternate location for the quota files, this is not recommended because the various quota utilities do not seem to handle this properly. At this point you should reboot your system with your new kernel. /etc/rc will automatically run the appropriate commands to create the initial quota files for all of the quotas you enabled in /etc/fstab, so there is no need to manually create any zero length quota files. In the normal course of operations you should not be required to run the quotacheck, quotaon, or quotaoff commands manually. However, you may want to read their manual pages just to be familiar with their operation. Setting Quota Limits disk quotas limits Once you have configured your system to enable quotas, verify that they really are enabled. An easy way to do this is to run: &prompt.root; quota -v You should see a one line summary of disk usage and current - quota limits for each file system that quotas are enabled + quota limits for each filesystem that quotas are enabled on. You are now ready to start assigning quota limits with the edquota command. You have several options on how to enforce limits on the amount of disk space a user or group may allocate, and how many files they may create. You may limit allocations based on disk space (block quotas) or number of files (inode quotas) or a combination of both. Each of these limits are further broken down into two categories: hard and soft limits. hard limit A hard limit may not be exceeded. Once a user reaches his hard limit he may not make any further allocations on the file system in question. For example, if the user has a hard limit of - 500 blocks on a file system and is currently using 490 blocks, the + 500 blocks on a filesystem and is currently using 490 blocks, the user can only allocate an additional 10 blocks. Attempting to allocate an additional 11 blocks will fail. soft limit Soft limits, on the other hand, can be exceeded for a limited amount of time. This period of time is known as the grace period, which is one week by default. If a user stays over his or her soft limit longer than the grace period, the soft limit will turn into a hard limit and no further allocations will be allowed. When the user drops back below the soft limit, the grace period will be reset. The following is an example of what you might see when you run the edquota command. When the edquota command is invoked, you are placed into the editor specified by the EDITOR environment variable, or in the vi editor if the EDITOR variable is not set, to allow you to edit the quota limits. &prompt.root; edquota -u test Quotas for user test: /usr: blocks in use: 65, limits (soft = 50, hard = 75) inodes in use: 7, limits (soft = 50, hard = 60) /usr/var: blocks in use: 0, limits (soft = 50, hard = 75) inodes in use: 0, limits (soft = 50, hard = 60) - You will normally see two lines for each file system that has + You will normally see two lines for each filesystem that has quotas enabled. One line for the block limits, and one line for inode limits. Simply change the value you want updated to modify the quota limit. For example, to raise this user's block limit from a soft limit of 50 and a hard limit of 75 to a soft limit of 500 and a hard limit of 600, change: /usr: blocks in use: 65, limits (soft = 50, hard = 75) to: /usr: blocks in use: 65, limits (soft = 500, hard = 600) The new quota limits will be in place when you exit the editor. Sometimes it is desirable to set quota limits on a range of uids. This can be done by use of the option on the edquota command. First, assign the desired quota limit to a user, and then run edquota -p protouser startuid-enduid. For example, if user test has the desired quota limits, the following command can be used to duplicate those quota limits for uids 10,000 through 19,999: &prompt.root; edquota -p test 10000-19999 For more information see &man.edquota.8;. Checking Quota Limits and Disk Usage disk quotas checking You can use either the quota or the repquota commands to check quota limits and disk usage. The quota command can be used to check individual user or group quotas and disk usage. A user may only examine his own quota, and the quota of a group he is a member of. Only the super-user may view all user and group quotas. The repquota command can be used to get a summary - of all quotas and disk usage for file systems with quotas + of all quotas and disk usage for filesystems with quotas enabled. The following is some sample output from the quota -v command for a user that has quota - limits on two file systems. + limits on two filesystems. Disk quotas for user test (uid 1002): Filesystem blocks quota limit grace files quota limit grace /usr 65* 50 75 5days 7 50 60 /usr/var 0 50 75 0 50 60 grace period - On the /usr file system in the above + On the /usr filesystem in the above example, this user is currently 15 blocks over the soft limit of 50 blocks and has 5 days of the grace period left. Note the asterisk * which indicates that the user is currently over his quota limit. - Normally file systems that the user is not using any disk + Normally filesystems that the user is not using any disk space on will not show up in the output from the quota command, even if he has a quota limit - assigned for that file system. The option - will display those file systems, such as the - /usr/var file system in the above + assigned for that filesystem. The option + will display those filesystems, such as the + /usr/var filesystem in the above example. Quotas over NFS NFS Quotas are enforced by the quota subsystem on the NFS server. The &man.rpc.rquotad.8; daemon makes quota information available to the &man.quota.1; command on NFS clients, allowing users on those machines to see their quota statistics. Enable rpc.rquotad in /etc/inetd.conf like so: rquotad/1 dgram rpc/udp wait root /usr/libexec/rpc.rquotad rpc.rquotad Now restart inetd: &prompt.root; kill -HUP `cat /var/run/inetd.pid` Mike Meyer Contributed by Creating and Using Optical Media (CDs & DVDs) CDROMs creating Introduction CDs have a number of features that differentiate them from conventional disks. Initially, they were not writable by the user. They are designed so that they can be read continuously without delays to move the head between tracks. They are also much easier to transport between systems than similarly sized media were at the time. CDs do have tracks, but this refers to a section of data to be read continuously and not a physical property of the disk. To produce a CD on FreeBSD, you prepare the data files that are going to make up the tracks on the CD, then write the tracks to the CD. ISO 9660 filesystems ISO-9660 - The ISO 9660 file system was designed to deal with these - differences. It unfortunately codifies file system limits that were + The ISO 9660 filesystem was designed to deal with these + differences. It unfortunately codifies filesystem limits that were common then. Fortunately, it provides an extension mechanism that allows properly written CDs to exceed those limits while still working with systems that do not support those extensions. mkisofs The mkisofs program is used to produce a data file containing an ISO 9660 file system. It has options that support various extensions, and is described below. You can install it with the sysutils/mkisofs ports. CD burner ATAPI Which tool to use to burn the CD depends on whether your CD burner is ATAPI or something else. ATAPI CD burners use the burncd program that is part of the base system. SCSI and USB CD burners should use cdrecord from the sysutils/cdrtools port. burncd has a limited number of supported drives. To find out if a drive is supported, see CD-R/RW supported drives. mkisofs - mkisofs produces an ISO 9660 file system - that is an image of a directory tree in the Unix file system name + mkisofs produces an ISO 9660 filesystem + that is an image of a directory tree in the Unix filesystem name space. The simplest usage is: &prompt.root; mkisofs imagefile.iso /path/to/tree filesystems ISO-9660 This command will create an imagefile - containing an ISO 9660 file system that is a copy of the tree at + containing an ISO 9660 filesystem that is a copy of the tree at /path/to/tree. In the process, it will map the file names to names that fit the limitations of the - standard ISO 9660 file system, and will exclude files that have - names uncharacteristic of ISO file systems. + standard ISO 9660 filesystem, and will exclude files that have + names uncharacteristic of ISO filesystems. filesystems HFS filesystems Joliet A number of options are available to overcome those restrictions. In particular, enables the Rock Ridge extensions common to Unix systems, enables Joliet extensions used by Microsoft systems, and - can be used to create HFS file systems used + can be used to create HFS filesystems used by MacOS. For CDs that are going to be used only on FreeBSD systems, can be used to disable all filename restrictions. When used with , it produces a - file system image that is identical to the FreeBSD tree you started + filesystem image that is identical to the FreeBSD tree you started from, though it may violate the ISO 9660 standard in a number of ways. CDROMs creating bootable The last option of general use is . This is used to specify the location of the boot image for use in producing an El Torito bootable CD. This option takes an argument which is the path to a boot image from the top of the tree being written to the CD. So, given that /tmp/myboot holds a bootable FreeBSD system with the boot image in /tmp/myboot/boot/cdboot, you could produce the - image of an ISO 9660 file system in + image of an ISO 9660 filesystem in /tmp/bootable.iso like so: &prompt.root; mkisofs boot/cdboot /tmp/bootable.iso /tmp/myboot Having done that, if you have vn - configured in your kernel, you can mount the file system with: + configured in your kernel, you can mount the filesystem with: &prompt.root; vnconfig vn0c /tmp/bootable.iso &prompt.root; mount cd9660 /dev/vn0c /mnt At which point you can verify that /mnt and /tmp/myboot are identical. There are many other options you can use with mkisofs to fine-tune its behavior. In particular: modifications to an ISO 9660 layout and the creation of Joilet and HFS discs. See the &man.mkisofs.8; manual page for details. burncd CDROMs burning If you have an ATAPI CD burner, you can use the burncd command to burn an ISO image onto a CD. burncd is part of the base system, installed as /usr/sbin/burncd. Usage is very simple, as it has few options: &prompt.root; burncd cddevice data imagefile.iso fixate Will burn a copy of imagefile.iso on cddevice. The default device is /dev/acd0c. See &man.burncd.8; for options to set the write speed, eject the CD after burning, and write audio data. cdrecord If you do not have an ATAPI CD burner, you will have to use cdrecord to burn your CDs. cdrecord is not part of the base system; you must install it from either the port at sysutils/cdrtools or the appropriate package. Changes to the base system can cause binary versions of this program to fail, possibly resulting in a coaster. You should therefore either upgrade the port when you upgrade your system, or if you are tracking -STABLE, upgrade the port when a new version becomes available. While cdrecord has many options, basic usage is even simpler than burncd. Burning an ISO 9660 image is done with: &prompt.root; cdrecord device imagefile.iso The tricky part of using cdrecord is finding the to use. To find the proper setting, use the flag of cdrecord, which might produce results like this: CDROMs burning &prompt.root; cdrecord Cdrecord 1.9 (i386-unknown-freebsd4.2) Copyright (C) 1995-2000 Jörg Schilling Using libscg version 'schily-0.1' scsibus0: 0,0,0 0) 'SEAGATE ' 'ST39236LW ' '0004' Disk 0,1,0 1) 'SEAGATE ' 'ST39173W ' '5958' Disk 0,2,0 2) * 0,3,0 3) 'iomega ' 'jaz 1GB ' 'J.86' Removable Disk 0,4,0 4) 'NEC ' 'CD-ROM DRIVE:466' '1.26' Removable CD-ROM 0,5,0 5) * 0,6,0 6) * 0,7,0 7) * scsibus1: 1,0,0 100) * 1,1,0 101) * 1,2,0 102) * 1,3,0 103) * 1,4,0 104) * 1,5,0 105) 'YAMAHA ' 'CRW4260 ' '1.0q' Removable CD-ROM 1,6,0 106) 'ARTEC ' 'AM12S ' '1.06' Scanner 1,7,0 107) * This lists the appropriate value for the devices on the list. Locate your CD burner, and use the three numbers separated by commas as the value for . In this case, the CRW device is 1,5,0, so the appropriate input would be =1,5,0. There are easier ways to specify this value; see &man.cdrecord.1; for details. That is also the place to look for information on writing audio tracks, controlling the speed, and other things. Duplicating Data CDs You can copy a data CD to a image file that is functionally equivalent to the image file created with mkisofs, and you can use it to duplicate any data CD. The example given here assumes that your CDROM device is acd0. Substitute your correct CDROM device. A c must be appended to the end of the device name to indicate the entire partition or, in the case of CDROMs, the entire disc. &prompt.root; dd if=/dev/acd0c of=file.iso bs=2048 Now that you have an image, you can burn it to CD as described above. This does not work with audio CDs. Using Data CDs Now that you have created a standard data CDROM, you probably want to mount it and read the data on it. By default, &man.mount.8; assumes that a filesystem is of type ufs. If you try something like: &prompt.root; mount /dev/cd0c/mnt you will get a complaint about Incorrect super block, and no mount. The CDROM is not a UFS filesystem, so attempts to mount it as such will fail. You just need to tell &man.mount.8; that the filesystem is of type ISO9660, and everything will work. You do this by specifying the option &man.mount.8;. For example, if you want to mount the CDROM device, /dev/cd0c, under /mnt, you would execute: &prompt.root; mount -t cd9660 /dev/cd0c /mnt Note that your device name (/dev/cd0c in this example) could be different, depending on the interface your CDROM uses. Also, the option just executes &man.mount.cd9660.8;. The above example could be shortened to: &prompt.root; mount_cd9660 /dev/cd0c /mnt You can generally use data CDROMs from any vendor in this way. Disks with certain ISO 9660 extensions might behave oddly, however. For example, Joliet disks store all filenames in two-byte Unicode characters. The FreeBSD kernel does not speak Unicode (yet!), so non-English characters show up as question marks. (If you are running FreeBSD 4.3 or later, the CD9660 driver includes hooks to load an appropriate Unicode conversion table on the fly. Modules for some of the common encodings are available via the sysutils/cd9660_unicode port.) Occasionally, you might get Device not configured when trying to mount a CDROM. This usually means that the CDROM drive thinks that there is no disk in the tray, or that the drive is not visible on the bus. It can take a couple of seconds for a CDROM drive to realize that it has been fed, so be patient. Sometimes, a SCSI CDROM may be missed because it didn't have enough time to answer the bus reset. If you have a SCSI CDROM please add the following option to your kernel configuration and rebuild your kernel. options SCSI_DELAY=15000 This tells your SCSI bus to pause 15 seconds during boot, to give your CDROM drive every possible chance to answer the bus reset. Burning Raw Data CDs You can choose to burn a file directly to CD, without creating an ISO 9660 filesystem. Some people do this for backup purposes. This runs more quickly than burning a standard CD: &prompt.root; burncd -f /dev/acd1c -s 12 data archive.tar.gz fixate In order to retrieve the data burned to such a CD, you must read data from the raw device node: &prompt.root; tar xzvf /dev/acd1c You cannot mount this disk as you would a normal CDROM. Such a CDROM cannot be read under any operating system except FreeBSD. If you want to be able to mount the CD, or share data with another operating system, you must use sysutils/mkisofs as described above. RAID Software RAID Christopher Shumway Written by Valentino Vaschetto Marked up by ccd (Concatenated Disk Configuration) It seems like today everyone has a collection of multimedia files. Everything from mp3's to video clips. I have converted most of my audio CDROM collection to mp3's so I can have all of my music in one centralized location, and not have to hunt down the audio CD with that one song I got stuck in my head. The problem I was faced with is where to store all these files? When choosing a mass storage solution, the most important factors to consider are speed, reliability, and cost. It is very rare to have all three in favor, normally a fast, reliable mass storage device is expensive, and to cut back on cost either speed or reliability must be sacrificed. In designing my system, I ranked the requirements by most favorable to least favorable. In this situation, cost was the biggest factor. I needed a lot of storage for a reasonable price. The next factor, speed, is not quite as important, since most of the usage would be over a one hundred megabit switched Ethernet, and that would most likely be the bottleneck. The ability to spread the file input/output operations out over several disks would be more than enough speed for this network. Finally, the consideration of reliability was an easy one to answer. All of the data being put on this mass storage device was already backed up on CD-R's. This drive was primarily here for online live storage for easy access, so if a drive went bad, I could just replace it, rebuild the filesystem, and copy back the data from CD-R's. To sum it up, I need something that will give me the most amount of storage space for my money. The cost of large IDE disks are cheap these days. I found a place that was selling Western Digital 30.7gb 5400 RPM IDE disks for about one-hundred and thirty US dollars. I bought three of them, giving me approximately ninety gigabytes of online storage. Installing the Hardware I installed the hard drives in a system that already had one IDE disk in as the system disk. The ideal solution would be for each IDE disk to have its own IDE controller and cable, but without fronting more costs to acquire a dual IDE controller this would not be a possibility. So, I jumpered two disks as slaves, and one as master. One went on the first IDE controller as a slave to the system disk, and the other two where slave/master on the secondary IDE controller. Upon reboot, the system BIOS was configured to automatically detect the disks attached. More importantly, FreeBSD detected them on reboot: ad0: 19574MB <WDC WD205BA> [39770/16/63] at ata0-master UDMA33 ad1: 29333MB <WDC WD307AA> [59598/16/63] at ata0-slave UDMA33 ad2: 29333MB <WDC WD307AA> [59598/16/63] at ata1-master UDMA33 ad3: 29333MB <WDC WD307AA> [59598/16/63] at ata1-slave UDMA33 At this point, if FreeBSD does not detect the disks, be sure that you have jumpered them correctly. I have heard numerous reports with problems using cable select instead of true slave/master configuration. The next consideration was how to attach them as part of the filesystem. I did a little research on &man.vinum.8; and FreeBSD's &man.ccd.4;. In this particular configuration, &man.ccd.4; appeared to be a better choice mainly because it has fewer parts. Less parts tends to indicate less chance of breakage. Vinum appears to be a bit of an overkill for my needs. Setting up the CCD CCD allows me to take several identical disks and concatenate them into one logical filesystem. In order to use ccd, I need a kernel with ccd support built into it. I added this line to my kernel configuration file and rebuilt the kernel: pseudo-device ccd 4 ccd support can also be loaded as a kernel loadable module in FreeBSD 4.0 or later. To set up ccd, first I need to disklabel the disks. Here is how I disklabeled them: disklabel -r -w ad1 auto disklabel -r -w ad2 auto disklabel -r -w ad3 auto This created a disklabel ad1c, ad2c and ad3c that spans the entire disk. The next step is to change the disklabel type. To do that I had to edit the disklabel: disklabel -e ad1 disklabel -e ad2 disklabel -e ad3 This opened up the current disklabel on each disk respectively in whatever editor the EDITOR environment variable was set to, in my case, &man.vi.1;. Inside the editor I had a section like this: 8 partitions: # size offset fstype [fsize bsize bps/cpg] c: 60074784 0 unused 0 0 0 # (Cyl. 0 - 59597) I needed to add a new "e" partition for &man.ccd.4; to use. This usually can be copied of the "c" partition, but the must be 4.2BSD. Once I was done, my disklabel should look like this: 8 partitions: # size offset fstype [fsize bsize bps/cpg] c: 60074784 0 unused 0 0 0 # (Cyl. 0 - 59597) e: 60074784 0 4.2BSD 0 0 0 # (Cyl. 0 - 59597) Building the Filesystem Now that I have all of the disks labeled, I needed to build the ccd. To do that, I used a utility called &man.ccdconfig.8;. ccdconfig takes several arguments, the first argument being the device to configure, in this case, /dev/ccd0c. The device node for ccd0c may not exist yet, so to create it, perform the following commands: cd /dev sh MAKEDEV ccd0 The next argument ccdconfig expects is the interleave for the filesystem. The interleave defines the size of a stripe in disk blocks, normally five hundred and twelve bytes. So, an interleave of thirty-two would be sixteen thousand three hundred and eighty-four bytes. After the interleave comes the flags for ccdconfig. If you want to enable drive mirroring, you can specify a flag here. In this configuration, I am not mirroring the ccd, so I left it as zero. The final arguments to ccdconfig are the devices to place into the array. Putting it all together I get this command: ccdconfig ccd0 32 0 /dev/ad1e /dev/ad2e /dev/ad3e This configures the ccd. I can now &man.newfs.8; the filesystem. newfs /dev/ccd0c Making it all Automatic Finally, if I want to be able to mount the ccd, I need to configure it first. I write out my current configuration to /etc/ccd.conf using the following command: ccdconfig -g > /etc/ccd.conf When I reboot, the script /etc/rc runs ccdconfig -C if /etc/ccd.conf exists. This automatically configures the ccd so it can be mounted. If you are booting into single user mode, before you can mount the ccd, you need to issue the following command to configure the array: ccdconfig -C Then, we need an entry for the ccd in /etc/fstab so it will be mounted at boot time. /dev/ccd0c /media ufs rw 2 2 vinum (Logical Volume Manager) XXX Hardware RAID RAID Hardware FreeBSD supports a wide variety of hardware RAID controllers from many popular manufacturers such as Adaptec, 3Ware, Mylex, DPT, AMI, Dell, HP, IBM, and more. The list of supported adapters is growing all the time, so make sure to check the release notes for complete information. Tape Backup Media tape media The major tape media are the 4mm, 8mm, QIC, mini-cartridge and DLT. 4mm (DDS: Digital Data Storage) tape media DDS (4mm) tapes tape media QIC tapes 4mm tapes are replacing QIC as the workstation backup media of choice. This trend accelerated greatly when Conner purchased Archive, a leading manufacturer of QIC drives, and then stopped production of QIC drives. 4mm drives are small and quiet but do not have the reputation for reliability that is enjoyed by 8mm drives. The cartridges are less expensive and smaller (3 x 2 x 0.5 inches, 76 x 51 x 12 mm) than 8mm cartridges. 4mm, like 8mm, has comparatively short head life for the same reason, both use helical scan. Data throughput on these drives starts ~150kB/s, peaking at ~500kB/s. Data capacity starts at 1.3 GB and ends at 2.0 GB. Hardware compression, available with most of these drives, approximately doubles the capacity. Multi-drive tape library units can have 6 drives in a single cabinet with automatic tape changing. Library capacities reach 240 GB. The DDS-3 standard now supports tape capacities up to 12 GB (or 24 GB compressed). 4mm drives, like 8mm drives, use helical-scan. All the benefits and drawbacks of helical-scan apply to both 4mm and 8mm drives. Tapes should be retired from use after 2,000 passes or 100 full backups. 8mm (Exabyte) tape media Exabyte (8mm) tapes 8mm tapes are the most common SCSI tape drives; they are the best choice of exchanging tapes. Nearly every site has an Exabyte 2 GB 8mm tape drive. 8mm drives are reliable, convenient and quiet. Cartridges are inexpensive and small (4.8 x 3.3 x 0.6 inches; 122 x 84 x 15 mm). One downside of 8mm tape is relatively short head and tape life due to the high rate of relative motion of the tape across the heads. Data throughput ranges from ~250kB/s to ~500kB/s. Data sizes start at 300 MB and go up to 7 GB. Hardware compression, available with most of these drives, approximately doubles the capacity. These drives are available as single units or multi-drive tape libraries with 6 drives and 120 tapes in a single cabinet. Tapes are changed automatically by the unit. Library capacities reach 840+ GB. The Exabyte Mammoth model supports 12 GB on one tape (24 GB with compression) and costs approximately twice as much as conventional tape drives. Data is recorded onto the tape using helical-scan, the heads are positioned at an angle to the media (approximately 6 degrees). The tape wraps around 270 degrees of the spool that holds the heads. The spool spins while the tape slides over the spool. The result is a high density of data and closely packed tracks that angle across the tape from one edge to the other. QIC tape media QIC-150 QIC-150 tapes and drives are, perhaps, the most common tape drive and media around. QIC tape drives are the least expensive "serious" backup drives. The downside is the cost of media. QIC tapes are expensive compared to 8mm or 4mm tapes, up to 5 times the price per GB data storage. But, if your needs can be satisfied with a half-dozen tapes, QIC may be the correct choice. QIC is the most common tape drive. Every site has a QIC drive of some density or another. Therein lies the rub, QIC has a large number of densities on physically similar (sometimes identical) tapes. QIC drives are not quiet. These drives audibly seek before they begin to record data and are clearly audible whenever reading, writing or seeking. QIC tapes measure (6 x 4 x 0.7 inches; 15.2 x 10.2 x 1.7 mm). Mini-cartridges, which also use 1/4" wide tape are discussed separately. Tape libraries and changers are not available. Data throughput ranges from ~150kB/s to ~500kB/s. Data capacity ranges from 40 MB to 15 GB. Hardware compression is available on many of the newer QIC drives. QIC drives are less frequently installed; they are being supplanted by DAT drives. Data is recorded onto the tape in tracks. The tracks run along the long axis of the tape media from one end to the other. The number of tracks, and therefore the width of a track, varies with the tape's capacity. Most if not all newer drives provide backward-compatibility at least for reading (but often also for writing). QIC has a good reputation regarding the safety of the data (the mechanics are simpler and more robust than for helical scan drives). Tapes should be retired from use after 5,000 backups. XXX* Mini-Cartridge DLT tape media DLT DLT has the fastest data transfer rate of all the drive types listed here. The 1/2" (12.5mm) tape is contained in a single spool cartridge (4 x 4 x 1 inches; 100 x 100 x 25 mm). The cartridge has a swinging gate along one entire side of the cartridge. The drive mechanism opens this gate to extract the tape leader. The tape leader has an oval hole in it which the drive uses to "hook" the tape. The take-up spool is located inside the tape drive. All the other tape cartridges listed here (9 track tapes are the only exception) have both the supply and take-up spools located inside the tape cartridge itself. Data throughput is approximately 1.5MB/s, three times the throughput of 4mm, 8mm, or QIC tape drives. Data capacities range from 10 GB to 20 GB for a single drive. Drives are available in both multi-tape changers and multi-tape, multi-drive tape libraries containing from 5 to 900 tapes over 1 to 20 drives, providing from 50 GB to 9 TB of storage. With compression, DLT Type IV format supports up to 70 GB capacity. Data is recorded onto the tape in tracks parallel to the direction of travel (just like QIC tapes). Two tracks are written at once. Read/write head lifetimes are relatively long; once the tape stops moving, there is no relative motion between the heads and the tape. AIT tape media AIT AIT is a new format from Sony, and can hold up to 50 GB (with compression) per tape. The tapes contain memory chips which retain an index of the tape's contents. This index can be rapidly read by the tape drive to determine the position of files on the tape, instead of the several minutes that would be required for other tapes. Software such as SAMS:Alexandria can operate forty or more AIT tape libraries, communicating directly with the tape's memory chip to display the contents on screen, determine what files were backed up to which tape, locate the correct tape, load it, and restore the data from the tape. Libraries like this cost in the region of $20,000, pricing them a little out of the hobbyist market. Using a New Tape for the First Time The first time that you try to read or write a new, completely blank tape, the operation will fail. The console messages should be similar to: sa0(ncr1:4:0): NOT READY asc:4,1 sa0(ncr1:4:0): Logical unit is in process of becoming ready The tape does not contain an Identifier Block (block number 0). All QIC tape drives since the adoption of QIC-525 standard write an Identifier Block to the tape. There are two solutions: mt fsf 1 causes the tape drive to write an Identifier Block to the tape. Use the front panel button to eject the tape. Re-insert the tape and dump data to the tape. dump will report DUMP: End of tape detected and the console will show: HARDWARE FAILURE info:280 asc:80,96. rewind the tape using: mt rewind. Subsequent tape operations are successful. Backup Programs backup software The three major programs are &man.dump.8;, &man.tar.1;, and &man.cpio.1;. Dump and Restore backup software dump / restore dump restore The traditional Unix backup programs are dump and restore. They operate on the drive as a collection of disk blocks, below the abstractions of files, links and directories that are created by the filesystems. dump backs up an entire filesystem on a device. It is unable to backup only part of a filesystem or a directory tree that spans more than one filesystem. dump does not write files and directories to tape, but rather writes the raw data blocks that comprise files and directories. If you use dump on your root directory, you would not back up /home, /usr or many other directories since these are typically mount points for other filesystems or symbolic links into those filesystems. dumphas quirks that remain from its early days in Version 6 of AT&T Unix (circa 1975). The default parameters are suitable for 9-track tapes (6250 bpi), not the high-density media available today (up to 62,182 ftpi). These defaults must be overridden on the command line to utilize the capacity of current tape drives. rhosts It is also possible to backup data across the network to a tape drive attached to another computer with rdump and rrestore. Both programs rely upon rcmd and ruserok to access the remote tape drive. Therefore, the user performing the backup must have rhosts access to the remote computer. The arguments to rdump and rrestore must be suitable to use on the remote computer. (e.g. When rdumping from a FreeBSD computer to an Exabyte tape drive connected to a Sun called komodo, use: /sbin/rdump 0dsbfu 54000 13000 126 komodo:/dev/nrsa8 /dev/rda0a 2>&1) Beware: there are security implications to allowing rhosts commands. Evaluate your situation carefully. It is also possible to use rdump and rrestore in a more secure fashion over ssh. Using <command>rdump</command> over <application>ssh</application> &prompt.root; /sbin/dump -0uan -f - /usr | gzip -2 | ssh1 -c blowfish \ targetuser@targetmachine.example.com dd of=/mybigfiles/dump-usr-l0.gz <command>tar</command> backup software tar &man.tar.1; also dates back to Version 6 of AT&T Unix (circa 1975). tar operates in cooperation with the filesystem; tar writes files and directories to tape. tar does not support the full range of options that are available from &man.cpio.1;, but tar does not require the unusual command pipeline that cpio uses. tar Most versions of tar do not support backups across the network. The GNU version of tar, which FreeBSD utilizes, supports remote devices using the same syntax as rdump. To tar to an Exabyte tape drive connected to a Sun called komodo, use: /usr/bin/tar cf komodo:/dev/nrsa8 . 2>&1. For versions without remote device support, you can use a pipeline and rsh to send the data to a remote tape drive. &prompt.root; tar cf - . | rsh hostname dd of=tape-device obs=20b If you are worried about the security of backing up over a network you should use the ssh command instead of rsh. <command>cpio</command> backup software cpio &man.cpio.1; is the original Unix file interchange tape program for magnetic media. cpio has options (among many others) to perform byte-swapping, write a number of different archive formats, and pipe the data to other programs. This last feature makes cpio and excellent choice for installation media. cpio does not know how to walk the directory tree and a list of files must be provided through stdin. cpio cpio does not support backups across the network. You can use a pipeline and rsh to send the data to a remote tape drive. &prompt.root; for f in directory_list; do find $f >> backup.list done &prompt.root; cpio -v -o --format=newc < backup.list | ssh user@host "cat > backup_device" Where directory_list is the list of directories you want to back up, user@host is the user/hostname combination that will be performing the backups, and backup_device is where the backups should be written to (e.g., /dev/nrsa0). <command>pax</command> backup software pax pax POSIX IEEE &man.pax.1; is IEEE/POSIX's answer to tar and cpio. Over the years the various versions of tar and cpio have gotten slightly incompatible. So rather than fight it out to fully standardize them, POSIX created a new archive utility. pax attempts to read and write many of the various cpio and tar formats, plus new formats of its own. Its command set more resembles cpio than tar. <application>Amanda</application> backup software Amanda Amanda Amanda (Advanced Maryland Network Disk Archiver) is a client/server backup system, rather than a single program. An Amanda server will backup to a single tape drive any number of computers that have Amanda clients and a network connection to the Amanda server. A common problem at sites with a number of large disks is that the length of time required to backup to data directly to tape exceeds the amount of time available for the task. Amanda solves this problem. Amanda can use a "holding disk" to backup several filesystems at the same time. Amanda creates "archive sets": a group of tapes used over a period of time to create full backups of all the filesystems listed in Amanda's configuration file. The "archive set" also contains nightly incremental (or differential) backups of all the filesystems. Restoring a damaged filesystem requires the most recent full backup and the incremental backups. The configuration file provides fine control of backups and the network traffic that Amanda generates. Amanda will use any of the above backup programs to write the data to tape. Amanda is available as either a port or a package, it is not installed by default. Do Nothing Do nothing is not a computer program, but it is the most widely used backup strategy. There are no initial costs. There is no backup schedule to follow. Just say no. If something happens to your data, grin and bear it! If your time and your data is worth little to nothing, then Do nothing is the most suitable backup program for your computer. But beware, Unix is a useful tool, you may find that within six months you have a collection of files that are valuable to you. Do nothing is the correct backup method for /usr/obj and other directory trees that can be exactly recreated by your computer. An example is the files that comprise the HTML or Postscript version of this Handbook. These document formats have been created from SGML input files. Creating backups of the HTML or PostScript files is not necessary. The SGML files are backed up regularly. Which Backup Program Is Best? LISA &man.dump.8; Period. Elizabeth D. Zwicky torture tested all the backup programs discussed here. The clear choice for preserving all your data and all the peculiarities of Unix filesystems is dump. Elizabeth created filesystems containing a large variety of unusual conditions (and some not so unusual ones) and tested each program by doing a backup and restore of those filesystems. The peculiarities included: files with holes, files with holes and a block of nulls, files with funny characters in their names, unreadable and unwritable files, devices, files that change size during the backup, files that are created/deleted during the backup and more. She presented the results at LISA V in Oct. 1991. See torture-testing Backup and Archive Programs. Emergency Restore Procedure Before the Disaster There are only four steps that you need to perform in preparation for any disaster that may occur. disklabel First, print the disklabel from each of your disks (e.g. disklabel da0 | lpr), your filesystem table (/etc/fstab) and all boot messages, two copies of each. fix-it floppies Second, determine that the boot and fix-it floppies (boot.flp and fixit.flp) have all your devices. The easiest way to check is to reboot your machine with the boot floppy in the floppy drive and check the boot messages. If all your devices are listed and functional, skip on to step three. Otherwise, you have to create two custom bootable floppies which have a kernel that can mount all of your disks and access your tape drive. These floppies must contain: fdisk, disklabel, newfs, mount, and whichever backup program you use. These programs must be statically linked. If you use dump, the floppy must contain restore. Third, create backup tapes regularly. Any changes that you make after your last backup may be irretrievably lost. Write-protect the backup tapes. Fourth, test the floppies (either boot.flp and fixit.flp or the two custom bootable floppies you made in step two.) and backup tapes. Make notes of the procedure. Store these notes with the bootable floppy, the printouts and the backup tapes. You will be so distraught when restoring that the notes may prevent you from destroying your backup tapes (How? In place of tar xvf /dev/rsa0, you might accidentally type tar cvf /dev/rsa0 and over-write your backup tape). For an added measure of security, make bootable floppies and two backup tapes each time. Store one of each at a remote location. A remote location is NOT the basement of the same office building. A number of firms in the World Trade Center learned this lesson the hard way. A remote location should be physically separated from your computers and disk drives by a significant distance. A Script for Creating a Bootable Floppy /mnt/sbin/init gzip -c -best /sbin/fsck > /mnt/sbin/fsck gzip -c -best /sbin/mount > /mnt/sbin/mount gzip -c -best /sbin/halt > /mnt/sbin/halt gzip -c -best /sbin/restore > /mnt/sbin/restore gzip -c -best /bin/sh > /mnt/bin/sh gzip -c -best /bin/sync > /mnt/bin/sync cp /root/.profile /mnt/root cp -f /dev/MAKEDEV /mnt/dev chmod 755 /mnt/dev/MAKEDEV chmod 500 /mnt/sbin/init chmod 555 /mnt/sbin/fsck /mnt/sbin/mount /mnt/sbin/halt chmod 555 /mnt/bin/sh /mnt/bin/sync chmod 6555 /mnt/sbin/restore # # create the devices nodes # cd /mnt/dev ./MAKEDEV std ./MAKEDEV da0 ./MAKEDEV da1 ./MAKEDEV da2 ./MAKEDEV sa0 ./MAKEDEV pty0 cd / # # create minimum filesystem table # cat > /mnt/etc/fstab < /mnt/etc/passwd < /mnt/etc/master.passwd < After the Disaster The key question is: did your hardware survive? You have been doing regular backups so there is no need to worry about the software. If the hardware has been damaged. First, replace those parts that have been damaged. If your hardware is okay, check your floppies. If you are using a custom boot floppy, boot single-user (type -s at the boot: prompt). Skip the following paragraph. If you are using the boot.flp and fixit.flp floppies, keep reading. Insert the boot.flp floppy in the first floppy drive and boot the computer. The original install menu will be displayed on the screen. Select the Fixit--Repair mode with CDROM or floppy. option. Insert the fixit.flp when prompted. restore and the other programs that you need are located in /mnt2/stand. Recover each filesystem separately. mount root partition disklabel newfs Try to mount (e.g. mount /dev/da0a /mnt) the root partition of your first disk. If the disklabel was damaged, use disklabel to re-partition and label the disk to match the label that you printed and saved. Use newfs to re-create the filesystems. Re-mount the root partition of the floppy read-write (mount -u -o rw /mnt). Use your backup program and backup tapes to recover the data for this filesystem (e.g. restore vrf /dev/sa0). Unmount the filesystem (e.g. umount /mnt) Repeat for each filesystem that was damaged. Once your system is running, backup your data onto new tapes. Whatever caused the crash or data loss may strike again. Another hour spent now may save you from further distress later. * I did not prepare for the Disaster, What Now? ]]> Julio Merino Contributed by Floppy disks Floppy disks are, nowadays, an old-fashioned medium to store/share data. Although, there are still some times when you need to use them, because you do not have any other removable storage media or you need to use what you have saved in them on any other computer. This section will explain how to use floppy disks in FreeBSD, that is, formating and copying/restoring data from them. But... I really have written this to help you about how to create forced-size floppies. The device Floppy disks are accessed through entries in /dev (like any other device). To access the raw floppy disk you can use /dev/rfdX, where X stands for the drive number, usually 0. When the disk is formatted you can use /dev/fdX, or whichever of the other devices named /dev/fdXY, where Y stands for a letter. These are all the same. Other important devices are /dev/fdX.size, where size is a floppy disk size in kilobytes. These entries are used at low-level format time to determine the disk size. Sometimes you will have to (re)create these entries under /dev. To do it, you can issue: &prompt.root; cd /dev && ./MAKEDEV "fd*" Formatting A floppy disk needs to be low-level formated before it can be used. This is usually done by the vendor but you may want to do it to check media integrity or to force the disk capacity to be bigger. To format the floppy at a low-level fashion you need to use fdformat. This utility expects the device name as an argument. We will use those /dev/fdX.size devices, which will allow us to format the floppy to its real size, or force them. So you insert a new 3.5inch floppy disk in your drive and issue: &prompt.root; /usr/sbin/fdformat /dev/rfd0.1440 This will take a while... You should notice any disk error here (this can help you determining which disks are good or bad). To force the floppy disk size, we will use other entries in /dev. Get the same floppy and issue: &prompt.root; /usr/sbin/fdformat /dev/rfd0.1720 It will take some more time than before (forced disks are slower). When it finishes, you will have a 1720kb floppy disk, but for the moment you will not notice any difference. You may use other disk sizes that you can find in /dev, but the most stable/compatible is the 1720kb for 3.5inch disks. The disklabel After low-level formatting the disk, you will need to place a disklabel on it. This disklabel will be destroyed later, but it is needed by the system to determine the size of the disk and its geometry later. The new disklabel will take over the whole disk, and will contain all the proper information about the geometry of the normal or forced floppy. Take a look to /etc/disktab now; you will see geometry values of all kinds of floppy disks. You can run now disklabel like: &prompt.root; /sbin/disklabel -B -r -w /dev/rfd0 fdsize Replace fdsize with fd1440, fd1720 or whichever size you want. The last field instructs disklabel which entry to take from /etc/disktab to use. The filesystem Now your floppy is ready to be high-level formated. This will place a new filesystem on it, which will let FreeBSD read and write to the disk. After creating the new filesystem, the disklabel is destroyed, so if you want to reformat the disk, you will have to recreate the disklabel another time. You can choose now which filesystem to use on your floppy. You can use UFS or FAT, though UFS is not a good idea for floppies. Choose FAT which is nice for floppies. To put a new filesystem on the floppy do this: &prompt.root; /sbin/newfs_msdos /dev/fd0 As we created a disklabel before, newfs will be able to fetch disk data and construct the new filesystem. And now, your disk is ready for use... Using the floppy You have two choices to use the floppy. You can either mount the disk with mount_msdos, or you can use mtools. Mtools are great, but you will need to install them from the ports system. Try it; issue a mdir. If you forced the disk, you will notice its extra size! A last note about forced disks: they are compatible with practically all other operating systems without any external utility to read/write them. Microsoft systems will recognize them without problems. But note that there may be times when the floppy drive itself is not able to read them (this may happen with very old drives). Backups to Floppies Can I Use floppies for Backing Up My Data? backup floppies floppy disks Floppy disks are not really a suitable media for making backups as: The media is unreliable, especially over long periods of time Backing up and restoring is very slow They have a very limited capacity (the days of backing up an entire hard disk onto a dozen or so floppies has long since passed). However, if you have no other method of backing up your data then floppy disks are better than no backup at all. If you do have to use floppy disks then ensure that you use good quality ones. Floppies that have been lying around the office for a couple of years are a bad choice. Ideally use new ones from a reputable manufacturer. So How Do I Backup My Data to Floppies? The best way to backup to floppy disk is to use tar with the (multi volume) option, which allows backups to span multiple floppies. To backup all the files in the current directory and sub-directory use this (as root): &prompt.root; tar Mcvf /dev/fd0 * When the first floppy is full tar will prompt you to insert the next volume (because tar is media independent it refers to volumes. In this context it means floppy disk) Prepare volume #2 for /dev/fd0 and hit return: This is repeated (with the volume number incrementing) until all the specified files have been archived. Can I Compress My Backups? tar gzip compression Unfortunately, tar will not allow the option to be used for multi-volume archives. You could, of course, gzip all the files, tar them to the floppies, then gunzip the files again! How Do I Restore My Backups? To restore the entire archive use: &prompt.root; tar Mxvf /dev/fd0 There are two ways that you can use to restore only specific files. First, you can start with the first floppy and use: &prompt.root; tar Mxvf /dev/fd0 filename tar will prompt you to insert subsequent floppies until it finds the required file. Alternatively, if you know which floppy the file is on then you can simply insert that floppy and use the same command as above. Note that if the first file on the floppy is a continuation from the previous one then tar will warn you that it cannot restore it, even if you have not asked it to! diff --git a/en_US.ISO8859-1/books/handbook/install/chapter.sgml b/en_US.ISO8859-1/books/handbook/install/chapter.sgml index c54ffe2e88..b4e47538f5 100644 --- a/en_US.ISO8859-1/books/handbook/install/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/install/chapter.sgml @@ -1,5362 +1,5362 @@ Jim Mock Restructured, reorganized, and parts rewritten by Randy Pratt The sysinstall walkthrough, screenshots, and general copy by Installing FreeBSD Synopsis installation FreeBSD is provided with a text-based, easy to use installation program called Sysinstall. This is the default installation program for FreeBSD, although vendors are free to provide their own installation suite if they wish. This chapter describes how to use Sysinstall to install FreeBSD. After reading this chapter, you will know: How to create the FreeBSD installation disks. How FreeBSD refers to, and subdivides, your hard disks. How to start Sysinstall. The questions Sysinstall will ask you, what they mean, and how to answer them. Before reading this chapter, you should: Read the supported hardware list that shipped with the version of FreeBSD you are installing, and verify that your hardware is supported. In general, these installation instructions are written for i386 (PC compatible) architecture computers. Where applicable, instructions specific to other platforms (for example, Alpha) will be listed. Pre-installation Tasks Inventory Your Computer Before installing FreeBSD you should attempt to inventory the components in your computer. The FreeBSD installation routines will show you the components (hard disks, network cards, CDROM drives, and so forth) with their model number and manufacturer. FreeBSD will also attempt to determine the correct configuration for these devices, which includes information about IRQ and IO port usage. Due to the vagaries of PC hardware this process is not always completely successful, and you may need to correct FreeBSD's determination of your configuration. If you already have another operating system installed, such as Windows or Linux, it is a good idea to use the facilities provided by those operating systems to see how your hardware is already configured. If you are really not sure what settings an expansion card is using, you may find it printed on the card itself. Popular IRQ numbers are 3, 5, and 7, and IO port addresses are normally written as hexadecimal numbers, such as 0x330. We recommend you print or write down this information before installing FreeBSD. It may help to use a table, like this: Sample Device Inventory Device Name IRQ IO port(s) Notes First hard disk N/A N/A 4GB, made by Seagate, first IDE master CDROM N/A N/A First IDE slave Second hard disk N/A N/A 2GB, made by IBM, second IDE master First IDE controller 14 0x1f0 Network card N/A N/A Intel 10/100 Modem N/A N/A 3Com 56K faxmodem, on COM1 …
Backup Your Data If the computer you will be installing FreeBSD on contains valuable data then ensure you have it backed up, and that you have tested the backups before installing FreeBSD. The FreeBSD installation routine will prompt you several times before writing any data to your disk, but once that process has started it cannot be undone. Decide Where to Install FreeBSD If you want FreeBSD to use all your disk, then there is nothing more to concern yourself with at this point — you can skip to the next section. However, if you need FreeBSD to co-exist with other operating systems then you need to have a rough understanding of how data is laid out on the disk, and how this affects you. Disk Layouts for the i386 A PC disk can be divided into discrete chunks. These chunks are called partitions. By design, the PC only supports four partitions per disk. These partitions are called primary partitions. To work around this limitation and allow more than four partitions, a new partition type was created, the extended partition. A disk may contain only one extended partition. Special partitions, called logical partitions, can be created inside this extended partition. Each partition has a partition ID, which is a number used to identify the type of data on the partition. FreeBSD partitions have the partition ID 165. In general, each operating system that you use will identify partitions in a particular way. For example, DOS, and its descendants, like Windows, assign each primary and logical partition a drive letter, starting with C:. FreeBSD must be installed into a primary partition. FreeBSD can keep all its data, including any files that you create, on this one partition. However, if you have multiple disks, then you can create a FreeBSD partition on all, or some, of them. When you install FreeBSD, you must have one partition available. This might be a blank partition that you have prepared, or it might be an existing partition that contains data that you no longer care about. If you are already using all the partitions on all your disks, then you will have to free one of them for FreeBSD using the tools provided by the other operating systems you use (e.g., fdisk on DOS or Windows). If you have a spare partition then you can use that. However, you may need to shrink one or more of your existing partitions first. A minimal installation of FreeBSD takes as little as 100MB of disk space. However, that is a very minimal install, leaving almost no space for your own files. A more realistic minimum is 250MB without a graphical environment, and 350MB or more if you want a graphical user interface. If you intend to install a lot of third party software as well, then you will need more space. You can use a commercial tool such as Partition Magic to resize your partitions to make space for FreeBSD. The tools directory on the CDROM contains two free software tools which can carry out this task, FIPS and PResizer. Documentation for both of these is in the same directory. Incorrect use of these tools can delete the data on your disk. Be sure that you have recent, working backups before using them. Using an existing partition unchanged Suppose that you have a computer with a single 4GB disk that already has a version of Windows installed, and you have split the disk into two drive letters, C: and D:, each of which is 2GB in size. You have 1GB of data on C:, and 0.5GB of data on D:. This means that your disk has two partitions on it, one per drive letter. You can copy all your existing data from D: to C:, which will free up the second partition, ready for FreeBSD. Shrinking an existing partition Suppose that you have a computer with a single 4GB disk, that already has a version of Windows installed. When you installed Windows you created one large partition, giving you a C: drive that is 4GB in size. You are currently using 1.5GB of space, and want FreeBSD to have 2GB of space. In order to install FreeBSD you will need to either: Backup your Windows data, and then reinstall Windows, asking for a 2GB partition at install time. Use one of the tools such as Partition Magic, described above, to shrink your Windows partition. Disk Layouts for the Alpha Alpha You will need a dedicated disk for FreeBSD on the Alpha. It is not possible to share a disk with another operating system at this time. Depending on the specific Alpha machine you have, this disk can either be a SCSI disk or an IDE disk, as long as your machine is capable of booting from it. Following the conventions of the Digital / Compaq manuals all SRM input is shown in uppercase. SRM is case insensitive. To find the names and types of disks in your machine, use the SHOW DEVICE command from the SRM console prompt: >>>show device dka0.0.0.4.0 DKA0 TOSHIBA CD-ROM XM-57 3476 dkc0.0.0.1009.0 DKC0 RZ1BB-BS 0658 dkc100.1.0.1009.0 DKC100 SEAGATE ST34501W 0015 dva0.0.0.0.1 DVA0 ewa0.0.0.3.0 EWA0 00-00-F8-75-6D-01 pkc0.7.0.1009.0 PKC0 SCSI Bus ID 7 5.27 pqa0.0.0.4.0 PQA0 PCI EIDE pqb0.0.1.4.0 PQB0 PCI EIDE This example is from a Digital Personal Workstation 433au and shows three disks attached to the machine. The first is a CDROM drive called DKA0 and the other two are disks and are called DKC0 and DKC100 respectively. Disks with names of the form DKx are SCSI disks. For example DKA100 refers to a SCSI with SCSI target ID 1 on the first SCSI bus (A), whereas DKC300 refers to a SCSI disk with SCSI ID 3 on the third SCSI bus (C). Devicename PKx refers to the SCSI host bus adapter. As seen in the SHOW DEVICE output SCSI CDROM drives are treated as any other SCSI hard disk drive. IDE disks have names similar to DQx, while PQx is the associated IDE controller. Collect Your Network Configuration Details If you intend to connect to a network as part of your FreeBSD installation (for example, if you will be installing from an FTP site, or an NFS server), then you need to know your network configuration. You will be prompted for this information during the installation so that FreeBSD can connect to the network to complete the install. Connecting to an Ethernet Network, or Cable/DSL Modem If you connect to an Ethernet network, or you have an Internet connection via cable or DSL, then you will need the following information: IP address. IP address of the default gateway. Hostname. DNS server IP addresses. If you do not know this information, then ask your system administrator or service provider. They may say that this information is assigned automatically, using DHCP. If so, make a note of this. Connecting Using a Modem If you dial up to an ISP using a regular modem then you can still install FreeBSD over the Internet, it will just take a very long time. You will need to know: The phone number to dial for your ISP. The COM: port your modem is connected to. The username and password for your ISP account. Check for FreeBSD Errata Although the FreeBSD project strives to ensure that each release of FreeBSD is as stable as possible, bugs do occasionally creep into the process. On very rare occasions those bugs affect the installation process. As these problems are discovered and fixed they are noted in the FreeBSD Errata, posted on the FreeBSD web site. You should check the errata before installing to make sure that there are no late-breaking problems which you should be aware of. Information about all the releases, including the errata for each release, can be found on the release information section of the FreeBSD web site. Prepare the Boot Discs FreeBSD can be installed from a number of different media; CDROM, DVD, FTP (both anonymous and non-anonymous), NFS, tape, or an existing MS-DOS partition. If you have FreeBSD on CDROM or DVD, and your computer allows you to boot from the CDROM or DVD (typically a BIOS option called Boot Order or similar) then you can skip this section. The FreeBSD CDROM and DVD images are bootable and can be used to install FreeBSD without any other special preparation. The FreeBSD installation process is started by booting your computer into the FreeBSD installer—it is not a program you run within another operating system. To do this, you must create some floppy disks that can be booted from, and then boot from them. If you are not installing directly from CDROM, DVD, or FTP then you are probably preparing your own installation media (e.g., an MS-DOS partition), which must be prepared before you install FreeBSD. This is a slightly more advanced, infrequent activity, and is documented in . This includes the scenario where you want to create your own FTP site on your own network so that other computers can use your site as a FreeBSD FTP installation site. In general, to create boot floppy images, follow these steps: Acquire the Boot Floppy Images The boot discs are available on your installation media in the floppies directory, and can also be downloaded from the floppies directory. The floppy images have a .flp extension. The floppies/ directory contains a number of different images, and the ones you will need to use depends on the version of FreeBSD you are installing, and in some cases, the hardware you are installing to. In most cases you will need two files, kern.flp and mfsroot.flp, but check README.TXT in the same directory to be sure. Your FTP program must use binary mode to download these disk images. Some web browsers have been known to use text (or ASCII) mode, which will be apparent if you cannot boot from the disks. Prepare the Floppy Disks You must prepare one floppy disk per image file you had to download. It is imperative that these disks are free from defects. The easiest way to test this is to format the disks for yourself. Do not trust pre-formatted floppies. If you try to install FreeBSD and the installation program crashes, freezes, or otherwise misbehaves, one of the first things to suspect is the floppies. Try writing the floppy image files to some other disks and try again. Write the Image Files to the Floppy Disks The .flp files are not regular files you copy to the disk. Instead, they are images of the complete contents of the disk. This means that you cannot use commands like DOS' copy to write the files. Instead, you must use specific tools to write the images directly to the disk. DOS If you are creating the floppies on a computer running DOS/Windows, then we provide a tool to do this called fdimage. If you are using the floppies from the CDROM, and your CDROM is the E: drive, then you would run this: E:\> tools\fdimage floppies\kern.flp A: Repeat this command for each .flp file, replacing the floppy disk each time, being sure to label the disks with the name of the file that you copied to them. Adjust the command line as necessary, depending on where you have placed the .flp files. If you do not have the CDROM, then fdimage can be downloaded from the tools directory on the FreeBSD FTP site. If you are writing the floppies on a Unix system (such as another FreeBSD system) you can use the &man.dd.1; command to write the image files directly to disk. On FreeBSD, you would run: &prompt.root; dd if=kern.flp of=/dev/fd0 On FreeBSD, /dev/fd0 refers to the first floppy disk (the A: drive). /dev/fd1 would be the B: drive, and so on. Other Unix variants might have different names for the floppy disk devices, and you will need to check the documentation for the system as necessary. You are now ready to start installing FreeBSD. Starting the Installation By default, the installation will not make any changes to your disk(s) until you see the following message: Last Chance: Are you SURE you want continue the installation? If you're running this on a disk with data you wish to save then WE STRONGLY ENCOURAGE YOU TO MAKE PROPER BACKUPS before proceeding! We can take no responsibility for lost disk contents! The install can be exited at any time prior to the final warning without changing the contents of the hard drive. If you are concerned that you have configured something incorrectly you can just turn the computer off before this point, and no damage will be done. Booting Booting for the i386 Start with your computer turned off. Turn on the computer. As it starts it should display an option to enter the system set up menu, or BIOS, commonly reached by keys like F2, F10, Del, or Alt S . Use whichever keystroke is indicated on screen. In some cases your computer may display a graphic while it starts. Typically, pressing Esc will dismiss the graphic and allow you to see the necessary messages. Find the setting that controls which devices the system boots from. This is commonly shown as a list of devices, such as Floppy, CDROM, First Hard Disk, and so on. If you needed to prepare boot floppies, then make sure that the floppy disk is selected. If you are booting from the CDROM then make sure that that is selected instead. In case of doubt, you should consult the manual that came with your computer, and/or its motherboard. Make the change, then save and exit. The computer should now restart. If you needed to prepare boot floppies, as described in then one of them will be the first boot disc, probably the one containing kern.flp. Put this disc in your floppy drive. If you are booting from CDROM, then you will need to turn on the computer, and insert the CDROM at the first opportunity. If your computer starts up as normal, and loads your existing operating system then either: The disks were not inserted early enough in the boot process. Leave them in, and try restarting your computer. The BIOS changes earlier did not work correctly. You should redo that step until you get the right option. FreeBSD will start to boot. If you are booting from CDROM you will see a display similar to this: Verifying DMI Pool Data ........ Boot from ATAPI CD-ROM : 1. FD 2.88MB System Type-(00) Uncompressing ... done BTX loader 1.00 BTX version is 1.01 Console: internal video/keyboard BIOS drive A: is disk0 BIOS drive B: is disk1 BIOS drive C: is disk2 BIOS drive C: is disk3 BIOS 639kB/261120kB available memory FreeBSD/i386 bootstrap loader, Revision 0.8 (murray@builder.freebsdmall.com, Thu Jan 17 19:28:57 PST 2002) /kernel text=0x266691 data=0x407c+0x20d68 \ | Hit [Enter] to boot immediately, or any other key for command prompt. Booting [kernel] in 9 seconds... _ If you are booting from floppy disc, you will see a display similar to this: Verifying DMI Pool Data ........ BTX loader 1.00 BTX version is 1.01 Console: internal video/keyboard BIOS drive A: is disk0 BIOS drive C: is disk1 BIOS 639kB/261120kB available memory FreeBSD/i386 bootstrap loader, Revision 0.8 (murray@builder.freebsdmall.com, Thu Jan 17 19:28:57 PST 2002) /kernel text=0x266691 data=0x407c+0x20d68 | Please insert MFS root floppy and press enter: Follow these instructions by removing the kern.flp disc, insert the mfsroot.flp disc, and press Enter. Irrespective of whether you booted from floppy or CDROM, the boot process will then get to this point: Hit [Enter] to boot immediately, or any other key for command prompt. Booting [kernel] in 9 seconds... _ Either wait ten seconds, or press Enter. This will then launch the kernel configuration menu. Booting for the Alpha Alpha Start with your computer turned off. Turn on the computer and wait for a boot monitor prompt. If you needed to prepare boot floppies, as described in then one of them will be the first boot disc, probably the one containing kern.flp. Put this disc in your floppy drive and type the following command to boot the disk (substituting the name of your floppy drive if necessary): >>>BOOT DVA0 -FLAGS '' -FILE '' If you are booting from CDROM, insert the CDROM into the drive and type the following command to start the installation (substituting the name of the appropriate CDROM drive if necessary): >>>BOOT DKA0 -FLAGS '' -FILE '' FreeBSD will start to boot. If you are booting from a floppy disc, at some point you will see the message: Please insert MFS root floppy and press enter: Follow these instructions by removing the kern.flp disc, insert the mfsroot.flp disc, and press Enter. Irrespective of whether you booted from floppy or CDROM, the boot process will then get to this point: Hit [Enter] to boot immediately, or any other key for command prompt. Booting [kernel] in 9 seconds... _ Either wait ten seconds, or press Enter. This will then launch the kernel configuration menu. Kernel Configuration The kernel is the core of the operating system. It is responsible for many things, including access to all the devices you may have on your system, such as hard disks, network cards, sound cards, and so on. Each piece of hardware supported by the FreeBSD kernel has a driver associated with it. Each driver has a two or three letter name, such as sa for the SCSI sequential access driver, or sio for the Serial I/O driver (which manages COM ports). When the kernel starts, each driver checks the system to see whether or not the hardware it supports exists on your system. If it does, then the driver configures the hardware and makes it available to the rest of the kernel. This checking is commonly referred to as device probing. Unfortunately, it is not always possible to do this in a safe way. Some hardware drivers do not co-exist well together, and probing for one piece of hardware can sometimes leave another in an inconsistent state. This is a basic limitation of the design of the PC. Many older devices are called ISA devices—as opposed to PCI devices. The ISA specification requires each device to have some information hard coded into it, typically the Interrupt Request Line number (IRQ) and IO port address that the driver uses. This information is commonly set by using physical jumpers on the card, or by using a DOS based utility. This was often a source of problems, because it was not possible to have two devices that shared the same IRQ or port address. Newer devices follow the PCI specification, which does not require this, as the devices are supposed to cooperate with the BIOS, and be told which IRQ and IO port addresses to use. If you have any ISA devices in your computer then FreeBSD's driver for that device will need to be configured with the IRQ and port address that you have set the card to. This is why carrying out an inventory of your hardware (see ) can be useful. Unfortunately, the default IRQs and memory ports used by some drivers clash. This is because some ISA devices are shipped with IRQs or memory ports that clash. The defaults in FreeBSD's drivers are deliberately set to mirror the manufacturer's defaults, so that, out of the box, as many devices as possible will work. This is almost never an issue when running FreeBSD day-to-day. Your computer will not normally contain two pieces of hardware that clash, because one of them would not work (irrespective of the operating system you are using). It becomes an issue when you are installing FreeBSD for the first time because the kernel used to carry out the install has to contain as many drivers as possible, so that many different hardware configurations can be supported. This means that some of those drivers will have conflicting configurations. The devices are probed in a strict order, and if you own a device that is probed late in the process, but conflicted with an earlier probe, then your hardware might not function or be probed correctly when you install FreeBSD. Because of this, the first thing you have the opportunity to do when installing FreeBSD is look at the list of drivers that are configured into the kernel, and either disable some of them, if you do not own that device, or confirm (and alter) the driver's configuration if you do own the device but the defaults are wrong. This probably sounds much more complicated than it actually is. shows the first kernel configuration menu. We recommend that you choose the Start kernel configuration in full-screen visual mode option, as it presents the easiest interface for the new user.
Kernel Configuration Menu
The kernel configuration screen () is then divided into four sections. A collapsible list of all the drivers that are currently marked as active, subdivided into groups such as Storage, and Network. Each driver is shown as a description, its two or three letter driver name, and the IRQ and memory port used by that driver. In addition, if an active driver conflicts with another active driver then CONF is shown next to the driver name. This section also shows the total number of conflicting drivers that are currently active. Drivers that have been marked inactive. They remain in the kernel, but they will not probe for their device when the kernel starts. These are subdivided into groups in the same way as the active driver list. More detail about the currently selected driver, including its IRQ and memory port address. Information about the keystrokes that are valid at this point in time.
The Kernel Device Configuration Visual Interface
At this point there will always be conflicts listed. Do not worry about this, it is to be expected; all the drivers are enabled, and as has already been explained, some of them will conflict with one another. You now have to work through the list of drivers, resolving the conflicts. Resolving Driver Conflicts Press X. This will completely expand the list of drivers, so you can see all of them. You will need to use the arrow keys to scroll back and forth through the active driver list. shows the result of pressing X.
Expanded Driver List
Disable all the drivers for devices that you do not have. To disable a driver, highlight it with the arrow keys and press Del. The driver will be moved to the Inactive Drivers list. If you inadvertently disable a device that you need then press Tab to switch to the Inactive Drivers list, select the driver that you disabled, and press Enter to move it back to the active list. Do not disable sc0. This controls the screen, and you will need this unless you are installing over a serial cable. Only disable atkbd0 if you are using a USB keyboard. If you have a normal keyboard then you must keep atkbd0. If there are no conflicts listed then you can skip this step. Otherwise, the remaining conflicts need to be examined. If they do not have the indication of an allowed conflict in the message area, then either the IRQ/address for device probe will need to be changed, or the IRQ/address on the hardware will need to be changed. To change the driver's configuration for IRQ and IO port address, select the device and press Enter. The cursor will move to the third section of the screen, and you can change the values. You should enter the values for IRQ and port address that you discovered when you made your hardware inventory. Press Q to finish editing the device's configuration and return to the active driver list. If you are not sure what these figures should be then you can try using -1. Some FreeBSD drivers can safely probe the hardware to discover what the correct value should be, and a value of -1 configures them to do this. The procedure for changing the address on the hardware varies from device to device. For some devices you may need to physically remove the card from your computer and adjust jumper settings or DIP switches. Other cards may have come with a DOS floppy that contains the programs used to reconfigure the card. In any case, you should refer to the documentation that came with the device. This will obviously entail restarting your computer, so you will need to boot back into the FreeBSD installation routine when you have reconfigured the card. When all the conflicts have been resolved the screen will look similar to .
Driver Configuration With No Conflicts
As you can see, the active driver list is now much smaller, with only drivers for the hardware that actually exists being listed. You can now save these changes, and move on to the next step of the install. Press Q to quit the device configuration interface. This message will appear: Save these parameters before exiting? ([Y]es/[N]o/[C]ancel) Answer Y to save the parameters and the probing will start. After displaying the probe results in white on black text Sysinstall will start and display its main menu ().
Sysinstall Main Menu
Reviewing the Device Probe Results The last few hundred lines that have been displayed on screen are stored and can be reviewed. To review the buffer, press Scroll Lock. This turns on scrolling in the display. You can then use the arrow keys, or PageUp and PageDown to view the results. Press Scroll Lock again to stop scrolling. Do this now, to review the text that scrolled off the screen when the kernel was carrying out the device probes. You will see text similar to , although the precise text will differ depending on the devices that you have in your computer.
Typical Device Probe Results avail memory = 254611456 (248644K bytes) Preloaded elf kernel "kernel" at 0xc069a000. Preloaded mfs_root "/mfsroot" at 0xc069a084. md1: Malloc disk npx0: <math processor> on motherboard npx0: INT 16 interface pcib0: <Host to PCI bridge> on motherboard pci0: <PCI bus> on pcib0 pcib1: <VIA 82C598MVP (Apollo MVP3) PCI-PCI (AGP bridge> at device 1.0 on pci0 pci1: <PCI bus> on pcib1 pci1: <Matrox MGA G200 AGP graphics accelerator> at 0.0 irq 11 isab0: <VIA 82C586 PCI-ISA bridge> at device 7.0 on pci0 isa0: <ISA bus> on isab0 atapci0: <VIA 82C586 ATA33 controller> port 0xe000-0xe00f at device 7.1 on pci0 ata0: at 0x1f0 irq 14 on atapci0 uhci0: <VIA 83C572 USB controller> port 0xe400-0xe41f irq 10 at device 7.2 on pci0 usb0: <VIA 83C572 USB controller> on uhci0 usb0: USB revision 1.0 uhub0: VIA UHCI root hub, class 9/0, rev 1.00/1.00, addr 1 uhub0: 2 ports with 2 removable, self powered chip1: <VIA 82C586B ACPI interface> at device 7.3 on pci0 ed0: <NE2000 PCI Ethernet (RealTek 8029)> port 0xe800-0xe81f irq 9 at device 10.0 on pci0 ed0: address 52:54:05:de:73:1b, type NE2000 (16bit) isa0: too many dependant configs (8) isa0: unexpected small tag 14 orm0; <Option ROM> at iomem 0xc0000-0xc7fff on isa0 fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq6 drq2 on isa0 fdc0: FIFO enabled, 8 bytes threshold fd0: <1440-KB 3.5" drive> on fdc0 drive 0 atkbdc0: <keyboard controller (i8042)> at port 0x60-0x64 on isa0 atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0 kbd0 at atkbd0 psm0: <PS/2 Mouse> irq 12 on atkbdc0 psm0: model Generic PS/2 mouse, device ID 0 vga0: <Generic ISA VGA> at port 0x3c0-0c3df iomem 0xa0000-0xbffff on isa0 sc0: <System console> at flags 0x100 on isa0 sc0: VGA <16 virtual consoles, flags-0x300> sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0 sio0: type 16550A sio1: at port 0x2f8-0x2ff irq3 on isa0 sio1: type 16550A ppc0: <Parallel port> at port 0x378-0x37f irq 7 on isa0 ppc0: SMC-like chipset (ECP/EPP/PS2/NIBBLE) in COMPATIBLE mode ppc0: FIFO with 16/16/15 bytes threshold ppbus0: IEEE1284 device found /NIBBLE Probing for PnP devices on ppbus0: ppi0: <Parallel I/O> on ppbus0 plip0: <PLIP network interface> on ppbus0 ad0: 8063MB <IBM-DHEA-38451> [16383/16/63] at ata0-master using UDMA33 acd0: CDROM <DELTA OTC-H101/ST3 F/W by OIPD> at ata0-slave using PIO4 Mounting root from ufs:/dev/md0c /stand/sysinstall running as init on vty0
Check the probe results carefully to make sure that FreeBSD found all the devices you expected. If a device was not found, then it will not be listed. If the device's driver required configuring with the IRQ and port address then you should check that you entered them correctly. If you need to make changes to the UserConfig device probing, its easy to exit the sysinstall program and start over again. Its also a good way to become more familiar with the process.
Select Sysinstall Exit
Use the arrow keys to select Exit Install from the Main Install Screen menu. The following message will display: User Confirmation Requested Are you sure you wish to exit? The system will reboot (be sure to remove any floppies from the drives). [ Yes ] No The install program will start again if the CDROM is left in the drive and [Yes] is selected. If you are booting from floppies it will be necessary to remove the mfsroot.flp floppy and replace it with kern.flp before rebooting. Introducing Sysinstall Sysinstall is the installation application provided by the FreeBSD Project. It is console based and is divided into a number of menus and screens that you can use to configure and control the installation process. The Sysinstall menu system is controlled by the arrow keys, Enter, Space, and other keys. A detailed description of these keys, and what they do, is contained in Sysinstall's usage information. To review this information, ensure that the Usage entry is highlighted and that the [Select] button is selected, as shown in , then press Enter. The instructions for using the menu system will be displayed. After reviewing them, press Enter to return to the Main Menu.
Selecting Usage From Sysinstall Main Menu
Selecting The Documentation Menu From the Main Menu, select Doc with the arrow keys and press Enter.
Selecting Documentation Menu
This will display the Documentation Menu.
Sysinstall Documentation Menu
It is important to read the documents provided. To view a document, select it with the arrow keys and press Enter. When finished reading a document, pressing Enter will return to the Documentation Menu. To return to the Main Installation Menu, select Exit with the arrow keys and press Enter. Selecting The Keymap Menu To change the keyboard mapping, use the arrow keys to select Keymap from the menu and press Enter.
Sysinstall Main Menu
A different keyboard mapping may be chosen by selecting the menu item using up/down arrow keys and pressing Space. Pressing Space again will unselect the item. When finished, choose the &gui.ok; using the arrow keys and press Enter. Only a partial list is shown in this screen representation. Selecting &gui.cancel; will use the default keymap and return to the Main Install Menu.
Sysinstall Keymap Menu
Installation Options Screen Select Options and press Enter.
Sysinstall Main Menu
Sysinstall Options
The default values are usually fine for most users and do not need to be changed. The description of the selected item will appear at the bottom of the screen highlighted in blue. Notice that one of the options is Use Defaults to reset all values to startup defaults. Press F1 to read the help screen about the various options. Pressing Q will return to the Main Install menu. Begin A Standard Installation The Standard installation is the option recommended for those new to Unix or FreeBSD. Use the arrow keys to select Standard and then press Enter to start the installation.
Begin Standard Installation
Allocating Disk Space Your first task is to allocate disk space for FreeBSD, and label that space so that Sysinstall can prepare it. In order to do this you need to know how FreeBSD expects to find information on the disk. BIOS Drive Numbering Before you install and configure FreeBSD on your system, there is an important subject that you should be aware of, especially if you have multiple hard drives. DOS Microsoft Windows In a PC running a BIOS-dependent operating system such as MS-DOS or Microsoft Windows, the BIOS is able to abstract the normal disk drive order, and the operating system goes along with the change. This allows the user to boot from a disk drive other than the so-called primary master. This is especially convenient for some users who have found that the simplest and cheapest way to keep a system backup is to buy an identical second hard drive, and perform routine copies of the first drive to the second drive using Ghost or XCOPY . Then, if the first drive fails, or is attacked by a virus, or is scribbled upon by an operating system defect, he can easily recover by instructing the BIOS to logically swap the drives. It is like switching the cables on the drives, but without having to open the case. SCSI BIOS More expensive systems with SCSI controllers often include BIOS extensions which allow the SCSI drives to be re-ordered in a similar fashion for up to seven drives. A user who is accustomed to taking advantage of these features may become surprised when the results with FreeBSD are not as expected. FreeBSD does not use the BIOS, and does not know the logical BIOS drive mapping. This can lead to very perplexing situations, especially when drives are physically identical in geometry, and have also been made as data clones of one another. When using FreeBSD, always restore the BIOS to natural drive numbering before installing FreeBSD, and then leave it that way. If you need to switch drives around, then do so, but do it the hard way, and open the case and move the jumpers and cables. An Illustration from the Files of Bill and Fred's Exceptional Adventures: Bill breaks-down an older Wintel box to make another FreeBSD box for Fred. Bill installs a single SCSI drive as SCSI unit zero and installs FreeBSD on it. Fred begins using the system, but after several days notices that the older SCSI drive is reporting numerous soft errors and reports this fact to Bill. After several more days, Bill decides it is time to address the situation, so he grabs an identical SCSI drive from the disk drive archive in the back room. An initial surface scan indicates that this drive is functioning well, so Bill installs this drive as SCSI unit four and makes an image copy from drive zero to drive four. Now that the new drive is installed and functioning nicely, Bill decides that it is a good idea to start using it, so he uses features in the SCSI BIOS to re-order the disk drives so that the system boots from SCSI unit four. FreeBSD boots and runs just fine. Fred continues his work for several days, and soon Bill and Fred decide that it is time for a new adventure -- time to upgrade to a newer version of FreeBSD. Bill removes SCSI unit zero because it was a bit flaky and replaces it with another identical disk drive from the archive. Bill then installs the new version of FreeBSD onto the new SCSI unit zero using Fred's magic Internet FTP floppies. The installation goes well. Fred uses the new version of FreeBSD for a few days, and certifies that it is good enough for use in the engineering department. It is time to copy all of his work from the old version. So Fred mounts SCSI unit four (the latest copy of the older FreeBSD version). Fred is dismayed to find that none of his precious work is present on SCSI unit four. Where did the data go? When Bill made an image copy of the original SCSI unit zero onto SCSI unit four, unit four became the new clone. When Bill re-ordered the SCSI BIOS so that he could boot from SCSI unit four, he was only fooling himself. FreeBSD was still running on SCSI unit zero. Making this kind of BIOS change will cause some or all of the Boot and Loader code to be fetched from the selected BIOS drive, but when the FreeBSD kernel drivers take-over, the BIOS drive numbering will be ignored, and FreeBSD will transition back to normal drive numbering. In the illustration at hand, the system continued to operate on the original SCSI unit zero, and all of Fred's data was there, not on SCSI unit four. The fact that the system appeared to be running on SCSI unit four was simply an artifact of human expectations. We are delighted to mention that no data bytes were killed or harmed in any way by our discovery of this phenomenon. The older SCSI unit zero was retrieved from the bone pile, and all of Fred's work was returned to him, (and now Bill knows that he can count as high as zero). Although SCSI drives were used in this illustration, the concepts apply equally to IDE drives. Disk Organization The smallest unit of organization that FreeBSD uses to find files is the filename. Filenames are case-sensitive, which means that readme.txt and README.TXT are two separate files. FreeBSD does not use the extension (.txt) of a file to determine whether the file is program, or a document, or some other form of data. Files are stored in directories. A directory may contain no files, or it may contain many hundreds of files. A directory can also contain other directories, allowing you to build up a hierarchy of directories within one another. This makes it much easier to organize your data. Files and directories are referenced by giving the file or directory name, followed by a forward slash, /, followed by any other directory names that are necessary. If you have directory foo, which contains directory bar, which contains the file readme.txt, then the full name, or path to the file is foo/bar/readme.txt. Directories and files are stored in a filesystem. Each filesystem contains exactly one directory at the very top level, called the root directory for that filesystem. This root directory can then contain other directories. So far this is probably similar to any other operating system you may have used. There are a few differences; for example, DOS uses \ to separate file and directory names, while MacOS uses :. FreeBSD does not use drive letters, or other drive names in the path. You would not write c:/foo/bar/readme.txt on FreeBSD. Instead, one filesystem is designated the root filesystem. The root filesystem's root directory is referred to as /. Every other filesystem is then mounted under the root filesystem. No matter how many disks you have on your FreeBSD system, every directory appears to be part of the same disk. Suppose you have three filesystems, called A, B, and C. Each filesystem has one root directory, which contains two other directories, called A1, A2 (and likewise B1, B2 and C1, C2). Call A the root filesystem. If you used the ls command to view the contents of this directory you would see two subdirectories, A1 and A2. The directory tree looks like this: / | +--- A1 | `--- A2 A filesystem must be mounted on to a directory in another filesystem. So now suppose that you mount filesystem B on to the directory A1. The root directory of B replaces A1, and the directories in B appear accordingly: / | +--- A1 | | | +--- B1 | | | `--- B2 | `--- A2 Any files that are in the B1 or B2 directories can be reached with the path /A1/B1 or /A1/B2 as necessary. Any files that were in /A1 have been temporarily hidden. They will reappear if B is unmounted from A. If B had been mounted on A2 then the diagram would look like this: / | +--- A1 | `--- A2 | +--- B1 | `--- B2 and the paths would be /A2/B1 and /A2/B2 respectively. Filesystems can be mounted on top of one another. Continuing the last example, the C filesystem could be mounted on top of the B1 directory in the B filesystem, leading to this arrangement: / | +--- A1 | `--- A2 | +--- B1 | | | +--- C1 | | | `--- C2 | `--- B2 Or C could be mounted directly on to the A filesystem, under the A1 directory: / | +--- A1 | | | +--- C1 | | | `--- C2 | `--- A2 | +--- B1 | `--- B2 If you are familiar with DOS, this is similar, although not identical, to the join command. This is not normally something you need to concern yourself with. Typically you create filesystems when installing FreeBSD and decide where to mount them, and then never change them unless you add a new disk. It is entirely possible to have one large root filesystem, and not need to create any others. There are some drawbacks to this approach, and one advantage. Benefits of multiple filesystems Different filesystems can have different mount options. For example, with careful planning, the root filesystem can be mounted read-only, making it impossible for you to inadvertently delete or edit a critical file. FreeBSD automatically optimizes the layout of files on a filesystem, depending on how the filesystem is being used. So a filesystem that contains many small files that are written frequently will have a different optimization to one that contains fewer, larger files. By having one big filesystem this optimization breaks down. FreeBSD's filesystems are very robust should you lose power. However, a power loss at a critical point could still damage the structure of the filesystem. By splitting your data over multiple filesystems it is more likely that the system will still come up, making it easier for you to restore from backup as necessary. Benefit of a single filesystem Filesystems are a fixed size. If you create a filesystem when you install FreeBSD and give it a specific size, you may later discover that you need to make the partition bigger. This is not easily accomplished without backing up, recreating the filesystems with the size, and then restoring. FreeBSD 4.4 and up have a featured command, the &man.growfs.8;, which will makes it possible to increase the size of a filesystem on the fly, removing this limitation. Filesystems are contained in partitions. This does not have the same meaning as the earlier usage of the term partition in this chapter, because of FreeBSD's Unix heritage. Each partition is identified by a letter, a through to h. Each partition can only contain one filesystem, which means that filesystems are often described by either their typical mount point on the root filesystem, or the letter of the partition they are contained in. FreeBSD also uses disk space for swap space. Swap space provides FreeBSD with virtual memory. This allows your computer to behave as though it has much more memory than it actually does. When FreeBSD runs out of memory it moves some of the data that is not currently being used to the swap space, and moves it back in (moving something else out) when it needs it. Some partitions have certain conventions associated with them. Partition Convention a Normally contains the root filesystem b Normally contains swap space c Normally the same size as the enclosing slice. This allows utilities that need to work on the entire slice (for example, a bad block scanner) to work on the c partition. You would not normally create a filesystem on this partition. d Partition d used to have a special meaning associated with it, although that is now gone. To this day, some tools may operate oddly if told to work on partition d, so Sysinstall will not normally create partition d. Each partition-that-contains-a-filesystem is stored in what FreeBSD calls a slice. Slice is FreeBSD's term for what were earlier called partitions, and again, this is because of FreeBSD's Unix background. Slices are numbered, starting at 1, through to 4. slices partitions dangerously dedicated Slice numbers follow the device name, prefixed with an s, starting at 1. So da0s1 is the first slice on the first SCSI drive. There can only be four physical slices on a disk, but you can have logical slices inside physical slices of the appropriate type. These extended slices are numbered starting at 5, so ad0s5 is the first extended slice on a disk. These devices are used by file systems that expect to occupy a slice. Slices, dangerously dedicated physical drives, and other drives contain partitions, which are represented as letters from a to h. This letter is appended to the device name, so da0a is the a partition on the first da drive, which is dangerously dedicated. ad1s3e is the fifth partition in the third slice of the second IDE disk drive. Finally, each disk on the system is identified. A disk name starts with a code that indicates the type of disk, and then a number, indicating which disk it is. Unlike slices, disk numbering starts at 0. Common codes that you will see are listed in . When referring to a partition FreeBSD requires that you also name the slice and disk that contains the partition, and when referring to a slice you should also refer to the disk name. Do this by listing the disk name, s, the slice number, and then the partition letter. Examples are shown in . shows a conceptual model of the disk layout that should help make things clearer. In order to install FreeBSD you must first configure the disk slices, then create partitions within the slice you will use for FreeBSD, and then create a filesystem (or swap space) in each partition, and decide where that filesystem will be mounted. Disk Device Codes Code Meaning ad ATAPI (IDE) disk da SCSI direct access disk acd ATAPI (IDE) CDROM cd SCSI CDROM fd Floppy disk
Sample Disk, Slice, and Partition Names Name Meaning ad0s1a The first partition (a) on the first slice (s1) on the first IDE disk (ad0). da1s2e The fifth partition (e) on the second slice (s2) on the second SCSI disk (da1). Conceptual Model of a Disk This diagram shows FreeBSD's view of the first IDE disk attached to the system. Assume that the disk is 4GB in size, and contains two 2GB slices (DOS partitions). The first slice contains a DOS disk, C:, and the second slice contains a FreeBSD installation. This example FreeBSD installation has three partitions, and a swap partition. The three partitions will each hold a filesystem. Partition a will be used for the root filesystem, e for the /var directory hierarchy, and f for the /usr directory hierarchy. .-----------------. --. | | | | DOS / Windows | | : : > First slice, ad0s1 : : | | | | :=================: ==: --. | | | Partition a, mounted as / | | | > referred to as ad0s2a | | | | | :-----------------: ==: | | | | Partition b, used as swap | | | > referred to as ad0s2b | | | | | :-----------------: ==: | Partition c, no | | | Partition e, used as /var > filesystem, all | | > referred to as ad0s2e | of FreeBSD slice, | | | | ad0s2c :-----------------: ==: | | | | | : : | Partition f, used as /usr | : : > referred to as ad0s2f | : : | | | | | | | | --' | `-----------------' --' Creating Slices using FDisk No changes you make at this point will be written to the disk. If you think you have made a mistake and want to start again you can use the menus to exit Sysinstall and try again. If you get confused and can not see how to exit you can always turn your computer off. After choosing to begin a standard installation in Sysinstall you will be shown this message: Message In the next menu, you will need to set up a DOS-style ("fdisk") partitioning scheme for your hard disk. If you simply wish to devote all disk space to FreeBSD (overwriting anything else that might be on the disk(s) selected) then use the (A)ll command to select the default partitioning scheme followed by a (Q)uit. If you wish to allocate only free space to FreeBSD, move to a partition marked "unused" and use the (C)reate command. [ OK ] [ Press enter to continue ] Press Enter as instructed. You will then be shown a list of all the hard drives that the kernel found when it carried out the device probes. shows an example from a system with two IDE disks. They have been called ad0 and ad2.
Select Drive for FDisk
You might be wondering why ad1 is not listed here. Why has it been missed? Consider what would happen if you had two IDE hard disks, one as the master on the first IDE controller, and one as the master on the second IDE controller. If FreeBSD numbered these as it found them, as ad0 and ad1 then everything would work. But if you then added a third disk, as the slave device on the first IDE controller, it would now be ad1, and the previous ad1 would become ad2. Because device names (such as ad1s1a) are used to find filesystems, you may suddenly discover that some of your filesystems no longer appear correctly, and you would need to change your FreeBSD configuration. To work around this, the kernel can be configured to name IDE disks based on where they are, and not the order in which they were found. With this scheme the master disk on the second IDE controller will always be ad2, even if there are no ad0 or ad1 devices. This configuration is the default for the FreeBSD kernel, which is why this display shows ad0 and ad2. The machine on which this screenshot was taken had IDE disks on both master channels of the IDE controllers, and no disks on the slave channels. You should select the disk on which you want to install FreeBSD, and then press &gui.ok;. FDisk will start, with a display similar to that shown in . The FDisk display is broken into three sections. The first section, covering the first two lines of the display, shows details about the currently selected disk, including its FreeBSD name, the disk geometry, and the total size of the disk. The second section shows the slices that are currently on the disk, where they start and end, how large they are, the name FreeBSD gives them, and their description and sub-type. This example shows two small unused slices, which are artifacts of disk layout schemes on the PC. It also shows one large FAT slice, which almost certainly appears as C: in DOS / Windows, and an extended slice, which may contain other drive letters for DOS / Windows. The third section shows the commands that are available in FDisk.
Typical Fdisk Partitions Before Editing
What you do now will depend on how you want to slice up your disk. If you want to use FreeBSD for the entire disk (which will delete all the other data on this disk when you confirm that you want Sysinstall to continue later in the installation process) then you can press A, which corresponds to the Use Entire Disk option. The existing slices will be removed, and replaced with a small area flagged as unused (again, an artifact of PC disk layout), and then one large slice for FreeBSD. If you do this then you should then select the newly created FreeBSD slice using the arrow keys, and press S to mark the slice as being bootable. The screen will then look very similar to . Note the A in the Flags column, which indicates that this slice is active, and will be booted from. If you will be deleting an existing slice to make space for FreeBSD then you should select the slice using the arrow keys, and then press D. You can then press C, and be prompted for size of slice you want to create. Enter the appropriate figure and press Enter. If you have already made space for FreeBSD (perhaps by using a tool such as Partition Magic) then you can press C to create a new slice. Again, you will be prompted for the size of slice you would like to create.
Fdisk Partition Using Entire Disk
When finished, press Q. Your changes will be saved in Sysinstall, but will not yet be written to disk. Install a Boot Manager You now have the option to install a boot manager. In general, you should choose to install the FreeBSD boot manager if: You have more than one drive, and have installed FreeBSD onto a drive other than the first one. You have installed FreeBSD alongside another operating system on the same disk, and you want to choose whether to start FreeBSD or the other operating system when you start the computer. Make your choice and press Enter.
Sysinstall Boot Manager Menu
The help screen, reached by pressing F1, discusses the problems that can be encountered when trying to share the hard disk between operating systems. Creating Slices on Another Drive If there is more than one drive, it will return to the Select Drives screen after the boot manager selection. If you wish to install FreeBSD on to more than one disk, then you can select another disk here and repeat the slice process using FDisk.
Exit Select Drive
The Tab key toggles between the last drive selected, &gui.ok;, and &gui.cancel;. Press the Tab once to toggle to the &gui.ok;, then press Enter to continue with the installation. Creating Partitions using <application>Disklabel</application> You must now create some partitions inside each slice that you have just created. Remember that each partition is lettered, from a through to h, and that partitions b, c, and d have conventional meanings that you should adhere to. Certain applications can benefit from particular partition schemes, especially if you are laying out partitions across more than one disk. However, for this, your first FreeBSD installation, you do not need to give too much thought to how you partition the disk. It is more important that you install FreeBSD and start learning how to use it. You can always re-install FreeBSD to change your partition scheme when you are more familiar with the operating system. This scheme features four partitions—one for swap space, and three for filesystems. Partition Layout for First Disk Partition Filesystem Size Description a / 100MB - This is the root file system. Every other filesystem + This is the root filesystem. Every other filesystem will be mounted somewhere under this one. 100MB is a reasonable size for this filesystem. You will not be storing too much data on it, as a regular FreeBSD install will put about 40MB of data here. The remaining space is for temporary data, and also leaves expansion space if future versions of FreeBSD need more space in /. b N/A 2-3 x RAM The system's swap space is kept on this partition. Choosing the right amount of swap space can be a bit of an art. A good rule of thumb is that your swap space should be two or three times as much as the available physical memory (RAM). You should also have at least 64MB of swap, so if you have less than 32MB of RAM in your computer then set the swap amount to 64MB. If you have more than one disk then you can put swap space on each disk. FreeBSD will then use each disk for swap, which effectively speeds up the act of swapping. In this case, calculate the total amount of swap you need (e.g., 128MB), and then divide this by the number of disks you have (e.g., two disks) to give the amount of swap you should put on each disk, in this example, 64MB of swap per disk. e /var 50MB The /var directory contains variable length files; log files, and other administrative files. Many of these files are read-from or written-to extensively during FreeBSD's day-to-day running. Putting these files on another filesystem allows FreeBSD to optimise the access of these files without affecting other files in other directories that do not have the same access pattern. f /usr Rest of disk All your other files will typically be stored in /usr, and its subdirectories.
If you will be installing FreeBSD on to more than one disk then you must also create partitions in the other slices that you configured. The easiest way to do this is to create two partitions on each disk, one for the swap space, and one for a filesystem. Partition Layout for Subsequent Disks Partition Filesystem Size Description b N/A See description As already discussed, you can split swap space across each disk. Even though the a partition is free, convention dictates that swap space stays on the b partition. e /diskn Rest of disk The rest of the disk is taken up with one big partition. This could easily be put on the a partition, instead of the e partition. However, convention says that the a partition on a slice is reserved for the filesystem that will be the root (/) filesystem. You do not have to follow this convention, but Sysinstall does, so following it yourself makes the installation slightly cleaner. You can choose to mount this filesystem anywhere; this example suggests that you mount them as directories /diskn, where n is a number that changes for each disk. But you can use another scheme if you prefer.
Having chosen your partition layout you can now create it using Sysinstall. You will see this message: Message Now, you need to create BSD partitions inside of the fdisk partition(s) just created. If you have a reasonable amount of disk space (200MB or more) and don't have any special requirements, simply use the (A)uto command to allocate space automatically. If you have more specific needs or just don't care for the layout chosen by (A)uto, press F1 for more information on manual layout. [ OK ] Press Enter to start the FreeBSD partition editor, called Disklabel. shows the display when you first start Disklabel. The display is divided in to three sections. The first few lines show the name of the disk you are currently working on, and the slice that contains the partitions you are creating (at this point Disklabel calls this the Partition name rather than slice name). This display also shows the amount of free space within the slice; that is, space that was set aside in the slice, but that has not yet been assigned to a partition. The middle of the display shows the partitions that have been created, the name of the filesystem that each partition contains, their size, and some options pertaining to the creation of the filesystem. The bottom third of the screen shows the keystrokes that are valid in Disklabel.
Sysinstall Disklabel Editor
Disklabel can automatically create partitions for you and assign them default sizes. Try this now, by Pressing A. You will see a display similar to that shown in . Depending on the size of the disk you are using the defaults may or may not be appropriate. This does not matter, as you do not have to accept the defaults. Beginning with FreeBSD 4.5, the default partitioning assigns the /tmp directory its own partition instead of being part of the / partition. This helps avoid filling the / partition with temporary files.
Sysinstall Disklabel Editor With Auto Defaults
To delete the suggested partitions, and replace them with your own, use the arrow keys to select the first partition, and press D to delete it. Repeat this to delete all the suggested partitions. To create the first partition (a, mounted as /), make sure the disk information at the top of the screen is selected, and press C. A dialog box will appear prompting you for the size of the new partition (as shown in ). You can enter the size as the number of disk blocks you want to use, or, more usefully, as a number followed by either M for megabytes, G for gigabytes, or C for cylinders.
Free Space For Root Partition
The default size shown will create a partition that takes up the rest of the slice. If you are using the partition sizes described earlier, then delete the existing figure using Backspace, and then type in 64M, as shown in . Then press &gui.ok;.
Edit Root Partition Size
Having chosen the partition's size you will then asked whether this partition will contain a filesystem or swap space. The dialog box is shown in . This first partition will contain a filesystem, so check that FS is selected and then press Enter.
Choose The Root Partition Type
Finally, because you are creating a filesystem, you must tell Disklabel where the filesystem is to be mounted. The dialog box is shown in . The root filesystem's mount point is /, so type /, and then press Enter.
Choose The Root Mount Point
The display will then update to show you the newly created partition. You should repeat this procedure for the other partitions. When you create the swap partition you will not be prompted for the filesystem mount point, as swap partitions are never mounted. When you create the final partition, /usr, you can leave the suggested size as is, to use the rest of the slice. Your final FreeBSD DiskLabel Editor screen will appear similar to , although your values chosen may be different. Press Q to finish.
Sysinstall Disklabel Editor
Choosing What To Install Select The Distribution Set Deciding which distribution set to install will depend largely on the intended use of the system and the amount of disk space available. The predefined options range from installing the smallest possible configuration to everything. Those who are new to Unix and/or FreeBSD should almost certainly select one of these canned options. Customizing a distribution set is typically for the more experienced user. Press F1 for more information on the distribution set options and what they contain. When finished reviewing the help, pressing Enter will return to the Select Distributions Menu. If a graphical user interface is desired then a distribution set that is preceded by an X should be chosen. The configuration of XFree86 and selection of a default desktop is part of the post-installation steps. The default XFree86 version installed is the 3.x branch. You should check to see whether your video card is supported at the XFree86 web site. If it is only supported under the 4.x branch, then you will need to install and configure XFree86 4.x after installation. Select a distribution without X and refer to for more information. If compiling a custom kernel is anticipated, select an option which includes the source code. For more information on why a custom kernel should be built or how to build a custom kernel see . Obviously, the most versatile system is one that includes everything. If there is adequate disk space, select All as shown in by using the arrow keys and press Enter. If there is a concern about disk space consider using an option that is more suitable for the situation. Other distributions can be added after installation.
Choose Distributions
Installing The Ports Collection After selecting the desired distribution, an opportunity to install the FreeBSD Ports Collection is presented. The ports collection is an easy and convenient way to install software. The ports collection does not contain the source code necessary to compile the software. It is a collection of files which automates the downloading, compiling and installation. discusses how to use the ports collection. The installation program does not check to see if you have adequate space. Select this option only if you have adequate hard disk space. User Confirmation Requested Would you like to install the FreeBSD ports collection? This will give you ready access to over &os.numports; ported software packages, at a cost of around 100MB of disk space when "clean" and possibly much more than that if a lot of the distribution tarballs are loaded (unless you have the extra CDs from a FreeBSD CD/DVD distribution available and can mount it on /cdrom, in which case this is far less of a problem). The ports collection is a very valuable resource and well worth having on your /usr partition, so it is advisable to say Yes to this option. For more information on the ports collection & the latest ports, visit: http://www.FreeBSD.org/ports [ Yes ] No Select [ Yes ] with the arrow keys to install the ports collection or [ No ] to skip this option. Press Enter to continue. The Choose Distributions menu will redisplay.
Confirm Distributions
If satisfied with the options, select Exit with the arrow keys, ensure that &gui.ok; is highlighted, and press Enter to continue. Choosing Your Installation Media If Installing from a CDROM, use the arrow keys to highlight Install from a FreeBSD CD/DVD. Ensure that &gui.ok; is highlighted, then press Enter to proceed with the installation. For other methods of installation, select the appropriate option and follow the instructions. Press F1 to display the Online Help for installation media. Press Enter to return to the media selection menu.
Choose Installation Media
FTP Installation Modes installation network FTP There are three FTP installation modes you can choose from: active FTP, passive FTP, or via a HTTP proxy. FTP Active, Install from an FTP server This option will make all FTP transfers use Active mode. This will not work through firewalls, but will often work with older FTP servers that do not support passive mode. If your connection hangs with passive mode (the default), try active! FTP Passive, Install from an FTP server through a firewall FTP Passive mode This option instructs FreeBSD to use Passive mode for all FTP operations. This allows the user to pass through firewalls that do not allow incoming connections on random port addresses. FTP via a HTTP proxy, Install from an FTP server through a http proxy FTP via a HTTP proxy This option instructs FreeBSD to use the HTTP protocol (like a web browser) to connect to a proxy for all FTP operations. The proxy will translate the requests and send them to the FTP server. This allows the user to pass through firewalls that do not allow FTP at all, but offer a HTTP proxy. In this case, you have to specify the proxy in addition to the FTP server. For a proxy FTP server, you should usually give the name of the server you really want as a part of the username, after an @ sign. The proxy server then fakes the real server. For example, assuming you want to install from ftp.FreeBSD.org, using the proxy FTP server foo.example.com, listening on port 1024. In this case, you go to the options menu, set the FTP username to ftp@ftp.FreeBSD.org, and the password to your email address. As your installation media, you specify FTP (or passive FTP, if the proxy supports it), and the URL ftp://foo.example.com:1234/pub/FreeBSD. Since /pub/FreeBSD from ftp.FreeBSD.org is proxied under foo.example.com, you are able to install from that machine (which will fetch the files from ftp.FreeBSD.org as your installation requests them). Committing to the Installation The installation can now proceed if desired. This is also the last chance for aborting the installation to prevent changes to the hard drive. User Confirmation Requested Last Chance! Are you SURE you want to continue the installation? If you're running this on a disk with data you wish to save then WE STRONGLY ENCOURAGE YOU TO MAKE PROPER BACKUPS before proceeding! We can take no responsibility for lost disk contents! [ Yes ] No Select [ Yes ] and press Enter to proceed. The installation time will vary according to the distribution chosen, installation media used, and the speed of the computer. There will be a series of messages displayed indicating the status. The installation is complete when the following message is displayed: Message Congratulations! You now have FreeBSD installed on your system. We will now move on to the final configuration questions. For any option you do not wish to configure, simply select No. If you wish to re-enter this utility after the system is up, you may do so by typing: /stand/sysinstall . [ OK ] [ Press enter to continue ] Press Enter to proceed with post-installation configurations. Selecting [ No ] and pressing Enter will abort the installation so no changes will be made to your system. The following message will appear: Message Installation complete with some errors. You may wish to scroll through the debugging messages on VTY1 with the scroll-lock feature. You can also choose "No" at the next prompt and go back into the installation menus to try and retry whichever operations have failed. [ OK ] This message is generated because nothing was installed. Pressing Enter will return to the Main Installation Menu to exit the installation. Post-installation Configuration of various options follows the successful installation. An option can be configured by re-entering the configuration options before booting the new FreeBSD system or after installation using /stand/sysinstall and selecting Configure. Network Device Configuration If you previously configured PPP for an FTP install, this screen will not display and can be configured later as described above. For detailed information on Local Area Networks and configuring FreeBSD as a gateway/router refer to the tutorial PPP - Pedantic PPP Primer. User Confirmation Requested Would you like to configure Ethernet or SLIP/PPP network devices? [ Yes ] No To configure a network device, select [ Yes ] and press Enter. Otherwise, select [ No ] to continue.
Selecting An Ethernet Device
Select the interface to be configured with the arrow keys and press Enter. User Confirmation Requested Do you want to try IPv6 configuration of the interface? Yes [ No ] In this private local area network the current Internet type protocol (IPv4) was sufficient and [ No ] was selected with the arrow keys and Enter pressed. If you want to try the new Internet protocol (IPv6), choose [ Yes ] and press Enter. It will take several seconds to scan for RA servers. User Confirmation Requested Do you want to try DHCP configuration of the interface? Yes [ No ] If DHCP (Dynamic Host Configuration Protocol) is not required select [ No ] with the arrow keys and press Enter. Selecting [ Yes ] will execute dhclient, and if successful, will fill in the network configuration information automatically. Refer to for more information. The following Network Configuration screen shows the configuration of the Ethernet device for a system that will act as the gateway for a Local Area Network.
Set Network Configuration For ed0
Use Tab to select the information fields and fill in appropriate information: Host The fully-qualified hostname, e.g. k6-2.example.com in this case. Domain The name of the domain that your machine is in, e.g. example.com for this case. IPv4 Gateway IP address of host forwarding packets to non-local destinations. Fill this in only if the machine is a node on the network. Leave this field blank if the machine is the gateway to the Internet for the network. Name server IP address of your local DNS server. There is no local DNS server on this private local area network so the IP address of the provider's DNS server (208.163.10.2) was used. IPv4 address The IP address to be used for this interface was 192.168.0.1 Netmask The address block being used for this local area network is a Class C block (192.168.0.0 - 192.168.255.255). The default netmask is for a Class C network (255.255.255.0). Extra options to ifconfig Any interface-specific options to ifconfig you would like to add. There were none in this case. Use Tab to select &gui.ok; when finished and press Enter. User Confirmation Requested Would you like to Bring Up the ed0 interface right now? [ Yes ] No Choosing [ Yes ] and pressing Enter will bring the machine up on the network and be ready for use after leaving the installation. Configure Gateway User Confirmation Requested Do you want this machine to function as a network gateway? [ Yes ] No If the machine will be acting as the gateway for a local area network and forwarding packets between other machines then select [ Yes ] and press Enter. If the machine is a node on a network then select [ No ] and press Enter to continue. Configure Internet Services User Confirmation Requested Do you want to configure inetd and the network services that it provides? Yes [ No ] If [ No ] is selected, various services such telnetd will not be enabled. This means that remote users will not be able to telnet into this machine. Local users will be still be able to access remote machines with telnet. These services can be enabled after installation by editing /etc/inetd.conf with your favorite text editor. See for more information. Select [ Yes ] if you wish to configure these services during install. An additional confirmation will display: User Confirmation Requested The Internet Super Server (inetd) allows a number of simple Internet services to be enabled, including finger, ftp and telnetd. Enabling these services may increase risk of security problems by increasing the exposure of your system. With this in mind, do you wish to enable inetd? [ Yes ] No Select [ Yes ] to continue. User Confirmation Requested inetd(8) relies on its configuration file, /etc/inetd.conf, to determine which of its Internet services will be available. The default FreeBSD inetd.conf(5) leaves all services disabled by default, so they must be specifically enabled in the configuration file before they will function, even once inetd(8) is enabled. Note that services for IPv6 must be seperately enabled from IPv4 services. Select [Yes] now to invoke an editor on /etc/inetd.conf, or [No] to use the current settings. [ Yes ] No Selecting [ Yes ] will allow adding services by deleting the # at the beginning of a line.
Editing <filename>inetd.conf</filename>
After adding the desired services, pressing Esc will display a menu which will allow exiting and saving the changes. Anonymous FTP User Confirmation Requested Do you want to have anonymous FTP access to this machine? Yes [ No ] Deny Anonymous FTP Selecting the default [ No ] and pressing Enter will still allow users who have accounts with passwords to use FTP to access the machine. Allow Anonymous FTP Anyone can access your machine if you elect to allow anonymous FTP connections. The security implications should be considered before enabling this option. For more information about security see . To allow anonymous FTP, use the arrow keys to select [ Yes ] and press Enter. The following screen (or similar) will display:
Default Anonymous FTP Configuration
Pressing F1 will display the help: This screen allows you to configure the anonymous FTP user. The following configuration values are editable: UID: The user ID you wish to assign to the anonymous FTP user. All files uploaded will be owned by this ID. Group: Which group you wish the anonymous FTP user to be in. Comment: String describing this user in /etc/passwd FTP Root Directory: Where files available for anonymous FTP will be kept. Upload subdirectory: Where files uploaded by anonymous FTP users will go. The ftp root directory will be put in /var by default. If you do not have enough room there for the anticipated FTP needs, the /usr directory could be used by setting the FTP Root Directory to /usr/ftp. When you are satisfied with the values, press Enter to continue. User Confirmation Requested Create a welcome message file for anonymous FTP users? [ Yes ] No If you select [ Yes ] and press Enter, an editor will automatically start allowing you to edit the message.
Edit The FTP Welcome Message
This is a text editor called ee. Use the instructions to change the message or change the message later using a text editor of your choice. Note the file name/location at the bottom of the editor screen. Press Esc and a pop-up menu will default to a) leave editor. Press Enter to exit and continue. Configure Network File Services Network File Services (NFS) allows sharing of files across a network. A machine can be configured as a server, a client, or both. Refer to for a more information. NFS Server User Confirmation Requested Do you want to configure this machine as an NFS server? Yes [ No ] If there is no need for a Network File System server or client, select [ No ] and press Enter. If [ Yes ] is chosen, a message will pop-up indicating that the exports file must be created. Message Operating as an NFS server means that you must first configure an /etc/exports file to indicate which hosts are allowed certain kinds of -access to your local file systems. +access to your local filesystems. Press [Enter] now to invoke an editor on /etc/exports [ OK ] Press Enter to continue. A text editor will start allowing the exports file to be created and edited.
Editing <filename>exports</filename>
Use the instructions to add the actual exported filesystems now or later using a text editor of your choice. Note the file name/location at the bottom of the editor screen. Press Esc and a pop-up menu will default to a) leave editor. Press Enter to exit and continue. NFS Client User Confirmation Requested Do you want to configure this machine as an NFS client? Yes [ No ] With the arrow keys, select [ Yes ] or [ No ] as appropriate and press Enter. Security Profile A security profile is a set of configuration options that attempts to achieve the desired ratio of security to convenience by enabling and disabling certain programs and other settings. The more severe the security profile, the fewer programs will be enabled by default. This is one of the basic principles of security: do not run anything except what you must. Please note that the security profile is just a default setting. All programs can be enabled and disabled after you have installed FreeBSD by editing or adding the appropriate line(s) to /etc/rc.conf. For more information, please see the &man.rc.conf.5; manual page. The following table describes what each of the security profiles does. The columns are the choices you have for a security profile, and the rows are the program or feature that the profile enables or disables. Possible security profiles Extreme Moderate &man.sendmail.8; NO YES &man.sshd.8; NO YES &man.portmap.8; NO MAYBE The portmapper is enabled if the machine has been configured as an NFS client or server earlier in the installation. NFS server NO YES &man.securelevel.8; YES If you choose a security profile that sets the securelevel to Extreme or High, you must be aware of the implications. Please read the &man.init.8; manual page and pay particular attention to the meanings of the security levels, or you may have significant trouble later! NO
User Confirmation Requested Do you want to select a default security profile for this host (select No for "medium" security)? [ Yes ] No Selecting [ No ] and pressing Enter will set the security profile to medium. Selecting [ Yes ] and pressing Enter will allow selecting a different security profile.
Security Profile Options
Press F1 to display the help. Press Enter to return to selection menu. Use the arrow keys to choose Medium unless your are sure that another level is required for your needs. With &gui.ok; highlighted, press Enter. An appropriate confirmation message will display depending on which security setting was chosen. Message Moderate security settings have been selected. Sendmail and SSHd have been enabled, securelevels are disabled, and NFS server setting have been left intact. PLEASE NOTE that this still does not save you from having to properly secure your system in other ways or exercise due diligence in your administration, this simply picks a standard set of out-of-box defaults to start with. To change any of these settings later, edit /etc/rc.conf [OK] Message Extreme security settings have been selected. Sendmail, SSHd, and NFS services have been disabled, and securelevels have been enabled. PLEASE NOTE that this still does not save you from having to properly secure your system in other ways or exercise due diligence in your administration, this simply picks a more secure set of out-of-box defaults to start with. To change any of these settings later, edit /etc/rc.conf [OK] Press Enter to continue with the post-installation configuration. The security profile is not a silver bullet! Even if you use the extreme setting, you need to keep up with security issues by reading an appropriate mailing list, using good passwords and passphrases, and generally adhering to good security practices. It simply sets up the desired security to convenience ratio out of the box. System Console Settings There are several options available to customize the system console. User Confirmation Requested Would you like to customize your system console settings? [ Yes ] No To view and configure the options, select [ Yes ] and press Enter.
System Console Configuration Options
A commonly used option is the screen saver. Use the arrow keys to select Saver and then press Enter.
Screen Saver Options
Select the desired screen saver using the arrow keys and then press Enter. The System Console Configuration menu will redisplay. The default time interval is 300 seconds. To change the time interval, select Saver again. At the Screen Saver Options menu, select Timeout using the arrow keys and press Enter. A pop-up menu will appear:
Screen Saver Timeout
The value can be changed, then select &gui.ok; and press Enter to return to the System Console Configuration menu.
System Console Configuration Exit
Selecting Exit and pressing Enter will continue with the post-installation configurations. Setting The Time Zone Setting the time zone for your machine will allow it to automatically correct for any regional time changes and perform other time zone related functions properly. The example shown is for a machine located in the Eastern time zone of the United States. Your selections will vary according to your geographical location. User Confirmation Requested Would you like to set this machine's time zone now? [ Yes ] No Select [ Yes ] and press Enter to set the time zone. User Confirmation Requested Is this machine's CMOS clock set to UTC? If it is set to local time or you don't know, please choose NO here! Yes [ No ] Select [ Yes ] or [ No ] according to how the machine's clock is configured and press Enter.
Select Your Region
The appropriate region is selected using the arrow keys and then press Enter.
Select Your Country
Select the appropriate country using the arrow keys and press Enter.
Select Your Time Zone
The appropriate time zone is selected using the arrow keys and pressing Enter. Confirmation Does the abbreviation 'EDT' look reasonable? [ Yes ] No Confirm the abbreviation for the time zone is correct. If it looks okay, press Enter to continue with the post-installation configuration. Linux Compatibility User Confirmation Requested Would you like to enable Linux binary compatibility? [ Yes ] No Selecting [ Yes ] and pressing Enter will allow running Linux software on FreeBSD. The install will proceed to add the appropriate packages for Linux compatibility. If installing by FTP, the machine will need to be connected to the Internet. Sometimes a remote ftp site will not have all the distributions like the Linux binary compatibility. This can be installed later if necessary. Mouse Settings This option will allow you to cut and paste text in the console and user programs with a 3-button mouse. If using a 2-button mouse, refer to manual page, &man.moused.8;, after installation for details on emulating the 3-button style. This example depicts a non-USB mouse. User Confirmation Requested Does this system have a non-USB mouse attached to it? [ Yes ] No Select [ Yes ] for a non-USB mouse or [ No ] for a USB mouse and press Enter.
Select Mouse Protocol Type
Use the arrow keys to select Type and press Enter
Set Mouse Protocol
The mouse used in this example is a PS/2 type, so the default Auto was appropriate. To change protocol, use the arrow keys to select another option. Ensure that &gui.ok; is highlighted and press Enter to exit this menu.
Configure Mouse Port
Use the arrow keys to select Port and press Enter.
Setting The Mouse Port
This system had a PS/2 mouse, so the default PS/2 was appropriate. To change the port, use the arrow keys and then press Enter.
Enable The Mouse Daemon
Last, the mouse daemon is enabled and tested.
Test The Mouse Daemon
The cursor moved around the screen so the mouse daemon is running: Select [ Yes ] to return to the previous menu then select Exit with the arrow keys and press Enter to return to continue with the post-installation configuration. Configure X-Server In order to use a graphical user interface such as KDE, GNOME, or others, the X server will need to be configured. To see whether your video card is supported, check the XFree86 web site. If your video card is only supported under XFree86 4.x, refer to for installation and configuration. User Confirmation Requested Would you like to configure your X server at this time? [ Yes ] No It is necessary to know your monitor specifications and video card information. Equipment damage can occur if settings are incorrect. If you do not have this information, select [ No ] and perform the configuration after installation when you have the information using /stand/sysinstall, selecting Configure and then XFree86. If you have graphics card and monitor information, select [ Yes ] and press Enter to proceed with configuring the X server.
Select Configuration Method Menu
There are several ways to configure the X server. XF86Setup is fully graphical and probably the easiest. Use the arrow keys to select the XF86Setup and press Enter. Message You have configured and been running the mouse daemon. Choose "/dev/sysmouse" as the mouse port and "SysMouse" or "MouseSystems" as the mouse protocol in the X configuration utility. [ OK ] [ Press enter to continue ] This indicates that the mouse daemon previously configured has been detected. Press Enter to continue. Press [Enter] to switch to graphics mode. This may take a while... [ OK ] Press Enter to switch to the graphics mode and continue. It will not try to switch to the graphics mode until Enter is pressed. The screen will go black and then shortly a screen with a large X in the center will appear. Be patient and wait. After a few more moments, the XF86Setup introduction will display. Read all instructions carefully. Press Enter to continue. <application>XF86Setup</application> Overview There are several areas of configuration to be completed. The configuration choices you make will depend on the hardware in the system so only a general overview can be given here. Along the top of the configuration tool there are buttons indicating the areas to be configured. You should be able to use the mouse if it was previously configured and select each item by clicking on it. Review each area and make appropriate selections for your system. <guimenuitem>Mouse</guimenuitem> The mouse is the first item to be configured. If you previously configured your mouse, the mouse daemon will already be running and should indicate SysMouse automatically for the mouse protocol. If you are use a two button mouse, you should also select Emulate3Buttons. There are other settings that can be tweaked if necessary. After completing your selections, click on the Apply and check the mouse actions are working properly. If further adjustment is needed, make them and recheck the operation by clicking on Apply again. When finished, move on to the next item. <guimenuitem>Keyboard</guimenuitem> Select the appropriate keyboard model. The default keyboard is Generic 101-key PC. Select the language layout for your keyboard. The default layout is U.S. English. If you are not using a U.S. keyboard, you may need to additionally select a variant. There are other options under Group Shift/Lock behavior and Control Key Position that can be selected if desired. Generally the default settings are fine. After completing the keyboard configuration, click on Apply and move on to the next item. <guimenuitem>Card</guimenuitem> Click on Read README file for additional help in configuring your video card. Select the appropriate video card from the list using the scrollbar. Clicking on your card will show as Card selected: above the list box. Next, the Detailed Setup was selected just to check details. Typically, if your video card was in the list, no changes will be needed here. When finished, move on to the next item. <guimenuitem>Monitor</guimenuitem> There are two ways to proceed. One method requires that you enter the horizontal and vertical sweep capabilities of your monitor in the text boxes. Choosing one of the monitor options listed that the monitor is the other method. After selecting a listed option, the horizontal and vertical sweep rates that will be used will display. Compare those to your monitor specifications. The monitor must be capable of using those ranges. Do not exceed the ratings of your monitor. Damage could occur. If you have doubts select ABORT and get the information. The remainder of the installation process will be unaffected and configuring the X-Server can be done later using /stand/sysinstall. When finished, move on to the next item. <guimenuitem>Mode</guimenuitem> Select the video mode(s) that you want to use. You can select more than one option. Typically, useful ranges are 640x480, 800x600, and 1024x768 but those are a function of video card capability, monitor size, and eye comfort. Next, select the default color depth you want to use. Your choices are 8bpp, 16bpp, 24bpp, and 32bpp. Select the highest color depth that your video card will support. When finished, move on to the next item. <guimenuitem>Other</guimenuitem> The default settings are reasonable values, so you probably will not need to change anything here. The default setting which allows the server to be killed with the hotkey sequence CtrlAlt Backspace should be left on. This can be executed if something is wrong with the server settings and prevent hardware damage. The default setting that allows video mode switching will permit changing of the mode while running X with the hotkey sequence Alt+ or Alt- . Testing the Server Verify all the settings once again and select Done and the following message will display: If you've finished configuring everything press the Okay button to start the X server using the configuration you've selected. If you still wish to configure some things, press one of the buttons at the top and then press "Done" again, when you've finished. After selecting Okay, some messages will briefly appear advising to wait and attempting to start the X-server. This process takes a few moments, so be patient. The screen will go blank for a short period of time and then a screen will appear with the message Congratulations, you've got a running server! If nothing appears or the display is distorted, kill the X-server using Ctrl Alt Backspace and adjust the settings or revisit them after installation. Running <command>xvidtune</command> The display can be adjusted for height, width, or centering by using xvidtune. There are warnings that improper settings can damage your equipment. Heed them. If in doubt, do not do it. Instead, use the monitor controls to adjust the display for x-windows. There may be some display differences when switching back to text mode, but it is better than damaging equipment. xvidtune can be ran later using /stand/sysinstall. Read the &man.xvidtune.1; man page before making any adjustments. Saving Configuration When you are satisfied, the configuration can now be saved. Select Save the configuration and Exit The configuration file will be saved to /etc/XF86Config. Once the configuration is done, the installation program will need to create a link to the server: Do you want to create an 'X' link to the SVGA server? (the link will be created in the directory: /usr/X11R6/bin) Okay? [ Yes ] No Select [ Yes ] and press Enter to create the link. Link created successfully. [ OK ] Press Enter to continue configuration. Select Default X Desktop There are a variety of window managers available. They range from very basic environments to full desktop environments with a large suite of software. Some require only minimal disk space and low memory while others with more features require much more. The best way to determine which is most suitable for you is to try a few different ones. Those are available from the ports collection or as packages and can be added after installation. You can select one of the popular desktops to be installed and configured as the default desktop. This will allow you to start it right after installation.
Select Default Desktop
Use the arrow keys to select a desktop and press Enter. Installation of the selected desktop will proceed. Install Packages The packages are pre-compiled binaries and are a convenient way to install software. Installation of one package is shown for purposes of illustration. Additional packages can also be added at this time if desired. After installation /stand/sysinstall can be used to add additional packages. User Confirmation Requested The FreeBSD package collection is a collection of hundreds of ready-to-run applications, from text editors to games to WEB servers and more. Would you like to browse the collection now? [ Yes ] No Selecting [ Yes ] and pressing Enter will be followed by the Package Selection screens:
Select Package Category
All packages available will be displayed if All is selected or you can select a particular category. Highlight your selection with the arrow keys and press Enter. A menu will display showing all the packages available for the selection made.
Select Packages
The bash shell is shown selected. Select as many as desired by highlighting the package and pressing the Space. A short description of each package will appear in the lower left corner of the screen. Pressing the Tab key will toggle between the last selected package, &gui.ok;, and &gui.cancel;. When you have finished marking the packages for installation, press Tab once to toggle to the &gui.ok; and press Enter to return to the Package Selection menu. The left and right arrow keys will also toggle between &gui.ok; and &gui.cancel;. This method can also be used to select &gui.ok; and press Enter to return to the Package Selection menu.
Install Packages
Use the arrow keys to select [ Install ] and press Enter. You will then need to confirm that you want to install the packages.
Confirm Package Installation
Selecting &gui.ok; and pressing Enter will start the package installation. Installing messages will appear until completed. Make note if there are any error messages. The final configuration continues after packages are installed. Add User/Groups You should add at least one user during the installation so that you can use the system without being logged in as root. The root partition is generally small and running applications as root can quickly fill it. A bigger danger is noted below: User Confirmation Requested Would you like to add any initial user accounts to the system? Adding at least one account for yourself at this stage is suggested since working as the "root" user is dangerous (it is easy to do things which adversely affect the entire system). [ Yes ] No Select [ Yes ] and press Enter to continue with adding a user.
Select Add User
Select Add User with the arrow keys and press Enter.
Add User Information
The following descriptions will appear in the lower part of the screen as the items are selected with Tab to assist with entering the required information. Login ID The login name of the new user (mandatory) UID The numerical ID for this user (leave blank for automatic choice) Group The login group name for this user (leave blank for automatic choice) Password The password for this user (enter this field with care!) Full name The user's full name (comment) Member groups The groups this user belongs to (i.e. gets access rights for) Home directory The user's home directory (leave blank for default) Login shell The user's login shell (leave blank for default). (/bin/sh) The login shell was changed from /bin/sh to /usr/local/bin/bash to use the bash shell that was previously installed as a package. Do not try to use a shell that does not exist or you will not be able to login. The user was also added to the group wheel to be able to become a superuser with root privileges. When you are satisfied, press &gui.ok; and the User and Group Management menu will redisplay.
Exit User and Group Management
Groups could also be added at this time if specific needs are known. Otherwise, this may be accessed through using /stand/sysinstall after installation is completed. When you are finished adding users, select Exit with the arrow keys and press Enter to continue the installation. Set <username>root</username> Password Message Now you must set the system manager's password. This is the password you'll use to log in as "root". [ OK ] [ Press enter to continue ] Press Enter to set the root password. The password will need to be typed in twice correctly. Needless to say, make sure you have a way of finding the password if you forget. Changing local password for root. New password : Retype new password : The installation will continue after the password is successfully entered. Exiting Install If you need to configure additional network devices or to do any other configurations, you can do it at this point or after installation with /stand/sysinstall. User Confirmation Requested Visit the general configuration menu for a chance to set any last options? Yes [ No ] Selecting [ No ] with the arrow keys and pressing Enter returns to the Main Installation Menu
Exit Install
Select [X Exit Install] with the arrow keys and press Enter. You will be asked to confirm exiting the installation: User Confirmation Requested Are you sure you wish to exit? The system will reboot (be sure to remove any floppies from the drives). [ Yes ] No Select [ Yes ] and remove floppy if booting from floppy. The CDROM drive is locked until the machine starts to reboot. The CDROM drive is then unlocked and can be removed from drive (quickly). The system will reboot so watch for any error messages that may appear. FreeBSD Bootup FreeBSD Bootup on the i386 If everything went well, you will see messages scroll off the screen and you will arrive at a login prompt. You can view the content of the messages by pressing Scroll-Lock and using PgUp and PgDn. Pressing Scroll-Lock again will return to the prompt. The entire message may not display (buffer limitation) but it can be viewed from the command line after logging in by typing dmesg at the prompt. Login using the username/password you set during installation (rpratt, in this example). Avoid logging in as root except when necessary. Typical boot messages: Copyright (c) 1992-2002 The FreeBSD Project. Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994 The Regents of the University of California. All rights reserved. FreeBSD 4.5-RC2 #0: Thu Jan 17 21:24:52 GMT 2002 murray@builder.freebsdmall.com:/usr/src/sys/compile/GENERIC Timecounter "i8254" frequency 1193182 Hz CPU: AMD-K6(tm) 3D processor (300.68-MHz 586-class CPU) Origin = "AuthenticAMD" Id = 0x580 Stepping = 0 Features=0x8001bf<FPU,VME,DE,PSE,TSC,MSR,MCE,CX8,MMX> AMD Features=0x80000800<SYSCALL,3DNow!> real memory = 268435456 (262144K bytes) config> di sn0 config> di lnc0 config> di le0 config> di ie0 config> di fe0 config> di cs0 config> di bt0 config> di aic0 config> di aha0 config> di adv0 config> q avail memory = 256311296 (250304K bytes) Preloaded elf kernel "kernel" at 0xc0491000. Preloaded userconfig_script "/boot/kernel.conf" at 0xc049109c. md0: Malloc disk Using $PIR table, 4 entries at 0xc00fde60 npx0: <math processor> on motherboard npx0: INT 16 interface pcib0: <Host to PCI bridge> on motherboard pci0: <PCI bus> on pcib0 pcib1: <VIA 82C598MVP (Apollo MVP3) PCI-PCI (AGP) bridge> at device 1.0 on pci0 pci1: <PCI bus> on pcib1 pci1: <Matrox MGA G200 AGP graphics accelerator> at 0.0 irq 11 isab0: <VIA 82C586 PCI-ISA bridge> at device 7.0 on pci0 isa0: <ISA bus> on isab0 atapci0: <VIA 82C586 ATA33 controller> port 0xe000-0xe00f at device 7.1 on pci0 ata0: at 0x1f0 irq 14 on atapci0 ata1: at 0x170 irq 15 on atapci0 uhci0: <VIA 83C572 USB controller> port 0xe400-0xe41f irq 10 at device 7.2 on pci0 usb0: <VIA 83C572 USB controller> on uhci0 usb0: USB revision 1.0 uhub0: VIA UHCI root hub, class 9/0, rev 1.00/1.00, addr 1 uhub0: 2 ports with 2 removable, self powered chip1: <VIA 82C586B ACPI interface> at device 7.3 on pci0 ed0: <NE2000 PCI Ethernet (RealTek 8029)> port 0xe800-0xe81f irq 9 at device 10.0 on pci0 ed0: address 52:54:05:de:73:1b, type NE2000 (16 bit) isa0: too many dependant configs (8) isa0: unexpected small tag 14 fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on isa0 fdc0: FIFO enabled, 8 bytes threshold fd0: <1440-KB 3.5" drive> on fdc0 drive 0 atkbdc0: <keyboard controller (i8042)> at port 0x60-0x64 on isa0 atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0 kbd0 at atkbd0 psm0: <PS/2 Mouse> irq 12 on atkbdc0 psm0: model Generic PS/2 mouse, device ID 0 vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0 sc0: <System console> at flags 0x1 on isa0 sc0: VGA <16 virtual consoles, flags=0x300> sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0 sio0: type 16550A sio1 at port 0x2f8-0x2ff irq 3 on isa0 sio1: type 16550A ppc0: <Parallel port> at port 0x378-0x37f irq 7 on isa0 ppc0: SMC-like chipset (ECP/EPP/PS2/NIBBLE) in COMPATIBLE mode ppc0: FIFO with 16/16/15 bytes threshold ppbus0: IEEE1284 device found /NIBBLE Probing for PnP devices on ppbus0: plip0: <PLIP network interface> on ppbus0 lpt0: <Printer> on ppbus0 lpt0: Interrupt-driven port ppi0: <Parallel I/O> on ppbus0 ad0: 8063MB <IBM-DHEA-38451> [16383/16/63] at ata0-master using UDMA33 ad2: 8063MB <IBM-DHEA-38451> [16383/16/63] at ata1-master using UDMA33 acd0: CDROM <DELTA OTC-H101/ST3 F/W by OIPD> at ata0-slave using PIO4 Mounting root from ufs:/dev/ad0s1a swapon: adding /dev/ad0s1b as swap device Automatic boot in progress... /dev/ad0s1a: FILESYSTEM CLEAN; SKIPPING CHECKS /dev/ad0s1a: clean, 48752 free (552 frags, 6025 blocks, 0.9% fragmentation) /dev/ad0s1f: FILESYSTEM CLEAN; SKIPPING CHECKS /dev/ad0s1f: clean, 128997 free (21 frags, 16122 blocks, 0.0% fragmentation) /dev/ad0s1g: FILESYSTEM CLEAN; SKIPPING CHECKS /dev/ad0s1g: clean, 3036299 free (43175 frags, 374073 blocks, 1.3% fragmentation) /dev/ad0s1e: filesystem CLEAN; SKIPPING CHECKS /dev/ad0s1e: clean, 128193 free (17 frags, 16022 blocks, 0.0% fragmentation) Doing initial network setup: hostname. ed0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500 inet 192.168.0.1 netmask 0xffffff00 broadcast 192.168.0.255 inet6 fe80::5054::5ff::fede:731b%ed0 prefixlen 64 tentative scopeid 0x1 ether 52:54:05:de:73:1b lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384 inet6 fe80::1%lo0 prefixlen 64 scopeid 0x8 inet6 ::1 prefixlen 128 inet 127.0.0.1 netmask 0xff000000 Additional routing options: IP gateway=YES TCP keepalive=YES routing daemons:. additional daemons: syslogd. Doing additional network setup:. Starting final network daemons: creating ssh RSA host key Generating public/private rsa1 key pair. Your identification has been saved in /etc/ssh/ssh_host_key. Your public key has been saved in /etc/ssh/ssh_host_key.pub. The key fingerprint is: cd:76:89:16:69:0e:d0:6e:f8:66:d0:07:26:3c:7e:2d root@k6-2.example.com creating ssh DSA host key Generating public/private dsa key pair. Your identification has been saved in /etc/ssh/ssh_host_dsa_key. Your public key has been saved in /etc/ssh/ssh_host_dsa_key.pub. The key fingerprint is: f9:a1:a9:47:c4:ad:f9:8d:52:b8:b8:ff:8c:ad:2d:e6 root@k6-2.example.com. setting ELF ldconfig path: /usr/lib /usr/lib/compat /usr/X11R6/lib /usr/local/lib a.out ldconfig path: /usr/lib/aout /usr/lib/compat/aout /usr/X11R6/lib/aout starting standard daemons: inetd cron sshd usbd sendmail. Initial rc.i386 initialization:. rc.i386 configuring syscons: blank_time screensaver moused. Additional ABI support: linux. Local package initilization:. Additional TCP options:. FreeBSD/i386 (k6-2.example.com) (ttyv0) login: rpratt Password: Generating the RSA and DSA keys may take some time on slower machines. This happens only on the initial boot-up of a new installation. Subsequent boots will be faster. If the X server has been configured and a Default Desktop chosen, it can be started by typing startx at the command line. Bootup of FreeBSD on the Alpha Alpha Once the install procedure has finished, you will be able to start FreeBSD by typing something like this to the SRM prompt: >>>BOOT DKC0 This instructs the firmware to boot the specified disk. To make FreeBSD boot automatically in the future, use these commands: >>> SET BOOT_OSFLAGS A >>> SET BOOT_FILE '' >>> SET BOOTDEF_DEV DKC0 >>> SET AUTO_ACTION BOOT The boot messages will be similar (but not identical) to those produced by FreeBSD booting on the i386. FreeBSD Shutdown It is important to properly shutdown the operating system. Do not just turn off power. First, become a superuser by typing su at the command line and entering the root password. This will work only if the user is a member of the group wheel. Otherwise, login as root and use shutdown -h now. The operating system has halted. Please press any key to reboot. It is safe to turn off the power after the shutdown command has been issued and the message Please press any key to reboot appears. If any key is pressed instead of turning off the power switch, the system will reboot. You could also use the CTRL+ALT+DEL key combination to reboot the system, however this is not recommended during normal operation. Supported Hardware hardware FreeBSD currently runs on a wide variety of ISA, VLB, EISA, and PCI bus-based PCs with Intel, AMD, Cyrix, or NexGen x86 processors, as well as a number of machines based on the Compaq Alpha processor. Support for generic IDE or ESDI drive configurations, various SCSI controllers, PCMCIA cards, USB devices, and network and serial cards is also provided. FreeBSD also supports IBM's microchannel (MCA) bus. A list of supported hardware is provided with each FreeBSD release in the FreeBSD Hardware Notes. This document can usually be found in a file named HARDWARE.TXT, in the top-level directory of a CDROM or FTP distribution or in sysinstall's documentation menu. It lists, for a given architecture, what hardware devices are known to be supported by each release of FreeBSD. Troubleshooting installation troubleshooting The following section covers basic installation troubleshooting, such as common problems people have reported. There are also a few questions and answers for people wishing to dual-boot FreeBSD with MS-DOS. What to Do If Something Goes Wrong... Due to various limitations of the PC architecture, it is impossible for probing to be 100% reliable, however, there are a few things you can do if it fails. Check the Hardware Notes document for your version of FreeBSD to make sure your hardware is supported. If your hardware is supported and you still experience lock-ups or other problems, reset your computer, and when the visual kernel configuration option is given, choose it. This will allow you to go through your hardware and supply information to the system about it. The kernel on the boot disks is configured assuming that most hardware devices are in their factory default configuration in terms of IRQs, IO addresses, and DMA channels. If your hardware has been reconfigured, you will most likely need to use the configuration editor to tell FreeBSD where to find things. It is also possible that a probe for a device not present will cause a later probe for another device that is present to fail. In that case, the probes for the conflicting driver(s) should be disabled. Some installation problems can be avoided or alleviated by by updating the firmware on various hardware components, most notably the motherboard. The motherboard firmware may also be referred to as BIOS and most of the motherboard or computer manufactures have a website where the upgrades and upgrade information may be located. Most manufacturers strongly advise against upgrading the motherboard BIOS unless there is a good reason for doing so, which could possibly be a critical update of sorts. The upgrade process can go wrong, causing permanent damage to the BIOS chip. Do not disable any drivers you will need during the installation, such as your screen (sc0). If the installation wedges or fails mysteriously after leaving the configuration editor, you have probably removed or changed something you should not have. Reboot and try again. In configuration mode, you can: List the device drivers installed in the kernel. Change device drivers for hardware that is not present in your system. Change IRQs, DRQs, and IO port addresses used by a device driver. After adjusting the kernel to match your hardware configuration, type Q to boot with the new settings. Once the installation has completed, any changes you made in the configuration mode will be permanent so you do not have to reconfigure every time you boot. It is still highly likely that you will eventually want to build a custom kernel. MS-DOS User's Questions and Answers DOS Many users wish to install FreeBSD on PCs inhabited by MS-DOS. Here are some commonly asked questions about installing FreeBSD on such systems. Help, I have no space! Do I need to delete everything first? If your machine is already running MS-DOS and has little or no free space available for the FreeBSD installation, all hope is not lost! You may find the FIPS utility, provided in the tools directory on the FreeBSD CDROM or various FreeBSD FTP sites to be quite useful. FIPS FIPS allows you to split an existing MS-DOS partition into two pieces, preserving the original partition and allowing you to install onto the second free piece. You first defragment your MS-DOS partition using the Windows DEFRAG utility (go into Explorer, right-click on the hard drive, and choose to defrag your hard drive), or Norton Disk Tools. You then must run FIPS. It will prompt you for the rest of the information it needs. Afterwards, you can reboot and install FreeBSD on the new free slice. See the Distributions menu for an estimate of how much free space you will need for the kind of installation you want. Partition Magic There is also a very useful product from PowerQuest called Partition Magic. This application has far more functionality than FIPS, and is highly recommended if you plan to often add/remove operating systems (like me). However, it does cost money, and if you plan to install FreeBSD once and then leave it there, FIPS will probably be fine for you. Can I use compressed MS-DOS filesystems from FreeBSD? No. If you are using a utility such as Stacker or DoubleSpace, FreeBSD will only be able to use whatever portion of the filesystem you leave uncompressed. The rest of the filesystem will show up as one large file (the stacked/double spaced file!). Do not remove that file or you will probably regret it greatly! It is probably better to create another uncompressed primary MS-DOS partition and use this for communications between MS-DOS and FreeBSD. Can I mount my extended MS-DOS partition? partitions slices Yes. DOS extended partitions are mapped in at the end of the other slices in FreeBSD, e.g., your D: drive might be /dev/da0s5, your E: drive, /dev/da0s6, and so on. This example assumes, of course, that your extended partition is on SCSI drive 0. For IDE drives, substitute ad for da appropriately if installing 4.0-RELEASE or later, and substitute wd for da if you are installing a version of FreeBSD prior to 4.0. You otherwise mount extended partitions exactly like you would any other DOS drive, for example: &prompt.root; mount -t msdos /dev/ad0s5 /dos_d Alpha User's Questions and Answers Alpha This section answers some commonly asked questions about installing FreeBSD on Alpha systems. Can I boot from the ARC or Alpha BIOS Console? ARC Alpha BIOS SRM No. &os;, like Compaq Tru64 and VMS, will only boot from the SRM console. Help, I have no space! Do I need to delete everything first? Unfortunately, yes. Can I mount my Compaq Tru64 or VMS filesystems? No, not at this time. Valentino Vaschetto Contributed by Advanced Installation Guide This section describes how to install FreeBSD in exceptional cases. Installing FreeBSD on a System without a Monitor or Keyboard installation headless (serial console) serial console This type of installation is called a headless install, because the machine that you are trying to install FreeBSD on either does not have a monitor attached to it, or does not even have a VGA output. How is this possible you ask? Using a serial console. A serial console is basically using another machine to act as the main display and keyboard for a system. To do this, just follow these steps: Fetch the Right Boot Floppy Images First you will need to get the right disk images so that you can boot into the install program. The secret with using a serial console is that you tell the boot loader to send I/O through a serial port instead of displaying console output to the VGA device and trying to read input from a local keyboard. Enough of that now, let's get back to getting these disk images. You will need to get kern.flp and mfsroot.flp from the floppies directory. Write the Image Files to the Floppy Disks The image files, such as kern.flp, are not regular files that you copy to the disk. Instead, they are images of the complete contents of the disk. This means that you can not use commands like DOS' copy to write the files. Instead, you must use specific tools to write the images directly to the disk. fdimage If you are creating the floppies on a computer running DOS then we provide a tool to do this called fdimage. If you are using the floppies from the CDROM, and your CDROM is the E: drive then you would run this: E:\> tools\fdimage floppies\kern.flp A: Repeat this command for each .flp file, replacing the floppy disk each time. Adjust the command line as necessary, depending on where you have placed the .flp files. If you do not have the CDROM then fdimage can be downloaded from the tools directory on the FreeBSD FTP site. If you are writing the floppies on a Unix system (such as another FreeBSD system) you can use the &man.dd.1; command to write the image files directly to disk. On FreeBSD you would run: &prompt.root; dd if=kern.flp of=/dev/fd0 On FreeBSD /dev/fd0 refers to the first floppy disk (the A: drive). /dev/fd1 would be the B: drive, and so on. Other Unix variants might have different names for the floppy disk devices, and you will need to check the documentation for the system as necessary. Enabling the Boot Floppies to Boot into a Serial Console Do not try to mount the floppy if it is write-protected mount If you were to boot into the floppies that you just made, FreeBSD would boot into its normal install mode. We want FreeBSD to boot into a serial console for our install. To do this, you have to mount the kern.flp floppy onto your FreeBSD system using the &man.mount.8; command. &prompt.root; mount /dev/fd0 /mnt Now that you have the floppy mounted, you must change into the floppy directory &prompt.root; cd /mnt Here is where you must set the floppy to boot into a serial console. You have to make a file called boot.config containing /boot/loader -h. All this does is pass a flag to the bootloader to boot into a serial console. &prompt.root; echo "/boot/loader -h" > boot.config Now that you have your floppy configured correctly, you must unmount the floppy using the &man.umount.8; command &prompt.root; cd / &prompt.root; umount /mnt Now you can remove the floppy from the floppy drive Connecting Your Null Modem Cable null-modem cable You now need to connect a null modem cable between the two machines. Just connect the cable to the serial ports of the 2 machines. A normal serial cable will not work here, you need a null modem cable because it has some of the wires inside crossed over. Booting Up for the Install It is now time to go ahead and start the install. Put the kern.flp floppy in the floppy drive of the machine you are doing the headless install on, and power on the machine. Connecting to Your Headless Machine cu Now you have to connect to that machine with &man.cu.1;: &prompt.root; cu -l /dev/cuaa0 That's it! You should be able to control the headless machine through your cu session now. It will ask you to put in the mfsroot.flp, and then it will come up with a selection of what kind of terminal to use. Just select the FreeBSD color console and proceed with your install! Preparing Your Own Installation Media To prevent repetition, FreeBSD disk in this context means a FreeBSD CDROM or DVD that you have purchased, or produced yourself. There may be some situations in which you need to create your own FreeBSD installation media and/or source. This might be physical media, such as a tape, or a source that Sysinstall can use to retrieve the files, such as a local FTP site, or an MS-DOS partition. For example: You have many machines connected to your local network, and one FreeBSD disk. You want to create a local FTP site using the contents of the FreeBSD disk, and then have your machines use this local FTP site instead of needing to connect to the Internet. You have a FreeBSD disk, FreeBSD does not recognize your CD/DVD drive, but DOS/Windows does. You want to copy the FreeBSD installations files to a DOS partition on the same computer, and then install FreeBSD using those files. The computer you want to install on does not have a CD/DVD drive, or a network card, but you can connect a Laplink-style serial or parallel cable to a computer that does. You want to create a tape that can be used to install FreeBSD. Creating a Local FTP Site with a FreeBSD Disk installation network FTP FreeBSD disks are laid out in the same way as the FTP site. This makes it very easy for you to create a local FTP site that can be used by other machines on your network when installing FreeBSD. On the FreeBSD computer that will host the FTP site, ensure that the CDROM is in the drive, and mounted on /cdrom. &prompt.root; mount /cdrom Create an account for anonymous FTP in /etc/passwd. Do this by editing /etc/passwd using &man.vipw.8; and adding this line. ftp:*:99:99::0:0:FTP:/cdrom:/nonexistent Ensure that the FTP service is enabled in /etc/inetd.conf. Anyone with network connectivity to your machine can now chose a media type of FTP and type in ftp://your machine after picking Other in the FTP sites menu during the install. This approach is OK for a machine that is on your local network, and that is protected by your firewall. Offering up FTP services to other machines over the Internet (and not your local network) exposes your computer to the attention of crackers and other undesirables. We strongly recommend that you follow good security practices if you do this. Creating Installation Floppies installation floppies If you must install from floppy disk (which we suggest you do not do), either due to unsupported hardware or simply because you insist on doing things the hard way, you must first prepare some floppies for the installation. At a minimum, you will need as many 1.44MB or 1.2MB floppies as it takes to hold all the files in the bin (binary distribution) directory. If you are preparing the floppies from DOS, then they MUST be formatted using the MS-DOS FORMAT command. If you are using Windows, use Explorer to format the disks (right-click on the A: drive, and select "Format". Do not trust factory pre-formatted floppies. Format them again yourself, just to be sure. Many problems reported by our users in the past have resulted from the use of improperly formatted media, which is why we are making a point of it now. If you are creating the floppies on another FreeBSD machine, a format is still not a bad idea, though you do not need to put a DOS filesystem on each floppy. You can use the disklabel and newfs commands to put a UFS filesystem on them instead, as the following sequence of commands (for a 3.5" 1.44MB floppy) illustrates: &prompt.root; fdformat -f 1440 fd0.1440 &prompt.root; disklabel -w -r fd0.1440 floppy3 &prompt.root; newfs -t 2 -u 18 -l 1 -i 65536 /dev/fd0 Use fd0.1200 and floppy5 for 5.25" 1.2MB disks. Then you can mount and write to them like any other filesystem. After you have formatted the floppies, you will need to copy the files to them. The distribution files are split into chunks conveniently sized so that 5 of them will fit on a conventional 1.44MB floppy. Go through all your floppies, packing as many files as will fit on each one, until you have all of the distributions you want packed up in this fashion. Each distribution should go into a subdirectory on the floppy, e.g.: a:\bin\bin.aa, a:\bin\bin.ab, and so on. Once you come to the Media screen during the install process, select Floppy and you will be prompted for the rest. Installing from an MS-DOS Partition installation from MS-DOS To prepare for an installation from an MS-DOS partition, copy the files from the distribution into a directory on that partition. For example, c:\freebsd. The directory structure of the CDROM or FTP site must be partially reproduced within this directory, so we suggest using the DOS xcopy command if you are copying it from a CD. For example, to prepare for a minimal installation of FreeBSD: C:\> md c:\freebsd C:\> xcopy e:\bin c:\freebsd\bin\ /s C:\> xcopy e:\manpages c:\freebsd\manpages\ /s Assuming that C: is where you have free space and E: is where your CDROM is mounted. If you do not have a CDROM drive, you can download the distribution from ftp.FreeBSD.org. Each distribution is in its own directory; for example, the bin distribution can be found in the &rel.current;/bin/ directory. For as many distributions you wish to install from an MS-DOS partition (and you have the free space for), install each one under c:\freebsd — the BIN distribution is the only one required for a minimum installation. Creating an Installation Tape installation from QIC/SCSI Tape Installing from tape is probably the easiest method, short of an online FTP install or CDROM install. The installation program expects the files to be simply tarred onto the tape. After getting all of the distribution files you are interested in, simply tar them onto the tape: &prompt.root; cd /freebsd/distdir &prompt.root; tar cvf /dev/rwt0 dist1 ... dist2 When you go to do the installation, you should also make sure that you leave enough room in some temporary directory (which you will be allowed to choose) to accommodate the full contents of the tape you have created. Due to the non-random access nature of tapes, this method of installation requires quite a bit of temporary storage. You should expect to require as much temporary storage as you have stuff written on tape. When starting the installation, the tape must be in the drive before booting from the boot floppy. The installation probe may otherwise fail to find it. Before Installing over a Network installation network serial (SLIP or PPP) installation network parallel (PLIP) installation network Ethernet There are three types of network installations you can do. Serial port (SLIP or PPP), Parallel port (PLIP (laplink cable)), or Ethernet (a standard Ethernet controller (includes some PCMCIA)). The SLIP support is rather primitive, and limited primarily to hard-wired links, such as a serial cable running between a laptop computer and another computer. The link should be hard-wired as the SLIP installation does not currently offer a dialing capability; that facility is provided with the PPP utility, which should be used in preference to SLIP whenever possible. If you are using a modem, then PPP is almost certainly your only choice. Make sure that you have your service provider's information handy as you will need to know it fairly early in the installation process. If you use PAP or CHAP to connect your ISP (in other words, if you can connect to the ISP in Windows without using a script), then all you will need to do is type in dial at the ppp prompt. Otherwise, you will need to know how to dial your ISP using the AT commands specific to your modem, as the PPP dialer provides only a very simple terminal emulator. Please refer to the user-ppp handbook and FAQ entries for further information. If you have problems, logging can be directed to the screen using the command set log local .... If a hard-wired connection to another FreeBSD (2.0-R or later) machine is available, you might also consider installing over a laplink parallel port cable. The data rate over the parallel port is much higher than what is typically possible over a serial line (up to 50kbytes/sec), thus resulting in a quicker installation. Finally, for the fastest possible network installation, an Ethernet adapter is always a good choice! FreeBSD supports most common PC Ethernet cards; a table of supported cards (and their required settings) is provided in the Hardware Notes for each release of FreeBSD. If you are using one of the supported PCMCIA Ethernet cards, also be sure that it is plugged in before the laptop is powered on! FreeBSD does not, unfortunately, currently support hot insertion of PCMCIA cards during installation. You will also need to know your IP address on the network, the netmask value for your address class, and the name of your machine. If you are installing over a PPP connection and do not have a static IP, fear not, the IP address can be dynamically assigned by your ISP. Your system administrator can tell you which values to use for your particular network setup. If you will be referring to other hosts by name rather than IP address, you will also need a name server and possibly the address of a gateway (if you are using PPP, it is your provider's IP address) to use in talking to it. If you want to install by FTP via a HTTP proxy (see below), you will also need the proxy's address. If you do not know the answers to all or most of these questions, then you should really probably talk to your system administrator or ISP before trying this type of installation. Before Installing via NFS installation network NFS The NFS installation is fairly straight-forward. Simply copy the FreeBSD distribution files you want onto a server somewhere and then point the NFS media selection at it. If this server supports only privileged port (as is generally the default for Sun workstations), you will need to set this option in the Options menu before installation can proceed. If you have a poor quality Ethernet card which suffers from very slow transfer rates, you may also wish to toggle the appropriate Options flag. In order for NFS installation to work, the server must support subdir mounts, e.g., if your FreeBSD 3.4 distribution directory lives on:ziggy:/usr/archive/stuff/FreeBSD, then ziggy will have to allow the direct mounting of /usr/archive/stuff/FreeBSD, not just /usr or /usr/archive/stuff. In FreeBSD's /etc/exports file, this is controlled by the . Other NFS servers may have different conventions. If you are getting permission denied messages from the server, then it is likely that you do not have this enabled properly.