book.sgml
No OneTemporary
Actions

Size

479 KB

Referenced Files

None

Subscribers

None

book.sgml
View Options

This file is larger than 256 KB, so syntax highlighting was skipped.

	<!DOCTYPE book PUBLIC "-//FreeBSD//DTD DocBook V4.1-Based Extension//EN" [
	<!ENTITY % books.ent PUBLIC "-//FreeBSD//ENTITIES DocBook FreeBSD Books Entity Set//EN">
	%books.ent;
	<!ENTITY bibliography SYSTEM "../../../share/sgml/bibliography.sgml">
	]>

	<book>
	<bookinfo>
	<title>Frequently Asked Questions for FreeBSD 5.X and 6.X</title>

	<corpauthor>The FreeBSD Documentation Project</corpauthor>

	<pubdate>$FreeBSD$</pubdate>

	<copyright>
	<year>1995</year>
	<year>1996</year>
	<year>1997</year>
	<year>1998</year>
	<year>1999</year>
	<year>2000</year>
	<year>2001</year>
	<year>2002</year>
	<year>2003</year>
	<year>2004</year>
	<year>2005</year>
	<year>2006</year>
	<year>2007</year>
	<year>2008</year>
	<holder>The FreeBSD Documentation Project</holder>
	</copyright>

	&bookinfo.legalnotice;

	<legalnotice id="trademarks" role="trademarks">
	&tm-attrib.freebsd;
	&tm-attrib.3com;
	&tm-attrib.adobe;
	&tm-attrib.creative;
	&tm-attrib.cvsup;
	&tm-attrib.ibm;
	&tm-attrib.ieee;
	&tm-attrib.intel;
	&tm-attrib.iomega;
	&tm-attrib.linux;
	&tm-attrib.microsoft;
	&tm-attrib.mips;
	&tm-attrib.netscape;
	&tm-attrib.opengroup;
	&tm-attrib.oracle;
	&tm-attrib.sgi;
	&tm-attrib.sparc;
	&tm-attrib.sun;
	&tm-attrib.usrobotics;
	&tm-attrib.xfree86;
	&tm-attrib.general;
	</legalnotice>

	<abstract>
	<para>This is the FAQ for FreeBSD versions 5.X and 6.X.
	All entries are assumed to be relevant to FreeBSD 5.X and
	later, unless otherwise noted. 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
	<ulink
	url="http://www.FreeBSD.org/doc/en_US.ISO8859-1/books/faq/index.html">FreeBSD
	World Wide Web server</ulink>. It may also be downloaded as
	one large <ulink url="book.html">HTML</ulink> file with HTTP
	or as plain text, &postscript;, PDF, etc. from the <ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/">FreeBSD FTP
	server</ulink>. You may also want to <ulink
	url="&url.base;/search/index.html">Search the
	FAQ</ulink>.</para>
	</abstract>
	</bookinfo>

	<chapter id="introduction">
	<title>Introduction</title>

	<para>Welcome to the FreeBSD 5.X-6.X FAQ!</para>

	<para>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.</para>

	<para>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.doc;.</para>

	<qandaset>
	<qandaentry>
	<question id="what-is-FreeBSD">
	<para>What is FreeBSD?</para>
	</question>

	<answer>
	<para>Briefly, FreeBSD is a &unix; like operating system for
	AMD64 and &intel; EM64T, &i386; PC-98, IA-64, &arm;, &powerpc;
	and &ultrasparc; platforms
	based on U.C. Berkeley's <quote>4.4BSD-Lite</quote>
	release, with some <quote>4.4BSD-Lite2</quote>
	enhancements. It is also based indirectly on William
	Jolitz's port of U.C. Berkeley's <quote>Net/2</quote> to
	the &i386;, known as <quote>386BSD</quote>, 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 <ulink url="&url.base;/index.html">FreeBSD home
	page</ulink>.</para>

	<para>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.</para>

	<para>For more detailed information on FreeBSD, please see the
	<ulink url="&url.books.handbook;/index.html">FreeBSD
	Handbook</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="FreeBSD-goals">
	<para>What is the goal of the FreeBSD Project?</para>
	</question>

	<answer>
	<para>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 definitely do not
	insist on it. We believe that our first and foremost
	<quote>mission</quote> 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.</para>

	<para>That code in our source tree which falls under the
	<ulink url="http://www.FreeBSD.org/copyright/COPYING">GNU
	General Public License (GPL)</ulink> or <ulink
	url="http://www.FreeBSD.org/copyright/COPYING.LIB">GNU
	Library General Public License (LGPL)</ulink> 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 <ulink
	url="http://www.FreeBSD.org/copyright/freebsd-license.html">
	FreeBSD license</ulink> whenever possible.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="bsd-license-restrictions">
	<para>Does the FreeBSD license have any restrictions?</para>
	</question>

	<answer>
	<para>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
	<ulink
	url="http://www.FreeBSD.org/copyright/freebsd-license.html">
	license</ulink>. For the simply curious, the license can
	be summarized like this.</para>

	<itemizedlist>
	<listitem>
	<para>Do not claim that you wrote this.</para>
	</listitem>

	<listitem>
	<para>Do not sue us if it breaks.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="replace-current-OS">
	<para>Can FreeBSD replace my current operating system?</para>
	</question>

	<answer>
	<para>For most people, yes. But this question is not quite
	that cut-and-dried.</para>

	<para>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 <ulink
	url="http://www.FreeBSD.org/ports/">Ports
	Collection</ulink>.</para>

	<para>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.</para>

	<para>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 &macos;, expect to
	invest additional time learning the &unix; way of doing
	things. This FAQ and the <ulink
	url="&url.books.handbook;/index.html">FreeBSD Handbook</ulink> are
	excellent places to start.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="why-called-FreeBSD">
	<para>Why is it called FreeBSD?</para>
	</question>

	<answer>
	<itemizedlist>
	<listitem>
	<para>It may be used free of charge, even by commercial
	users.</para>
	</listitem>

	<listitem>
	<para>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).</para>
	</listitem>

	<listitem>
	<para>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).</para>
	</listitem>
	</itemizedlist>

	<para>It is worth pointing out that the word
	<quote>free</quote> is being used in two ways here, one meaning
	<quote>at no cost</quote>, the other meaning <quote>you can do
	whatever you like</quote>. Apart from one or two things you
	<emphasis>cannot</emphasis> do with the FreeBSD code, for
	example pretending you wrote it, you can really do whatever you
	like with it.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="differences-to-other-bsds">
	<para>What are the differences between FreeBSD and NetBSD, OpenBSD,
	and other open source BSD operating systems?</para>
	</question>

	<answer>
	<para>James Howard wrote a good explanation of the history
	and differences between the various projects for <ulink
	url="http://www.daemonnews.org/">DaemonNews</ulink>,
	called <ulink
	url="http://ezine.daemonnews.org/200104/bsd_family.html">The
	BSD Family Tree</ulink> which goes a fair way to answering
	this question.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="latest-version">
	<para>What is the latest version of FreeBSD?</para>
	</question>

	<!--
	This answer is a hack to deal with the fact that for now there are
	multiple "latest" versions of FreeBSD.
	-->

	<answer>
	<para>At this point in FreeBSD's development, there are two
	parallel development branches; releases are being made from
	both branches. The 5.X series of releases
	is being made from the <emphasis>5-STABLE</emphasis> branch
	and the 6.X series of releases from <emphasis>6-STABLE</emphasis>.</para>

	<para>Up until the release of 5.3, the 4.X series was the
	one known as <emphasis>-STABLE</emphasis>. However,
	as of 5.3, the 4.X branch will be designated for
	an <quote>extended support</quote> status and receive
	only fixes for major problems, such as security-related
	fixes. There will be more releases made from the
	<emphasis>5-STABLE</emphasis> branch, but it is considered
	a <quote>legacy</quote> branch and most current work will
	only become a part of <emphasis>6-STABLE</emphasis>.</para>

	<para>Version <ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel.current;-RELEASE/">&rel.current;</ulink>
	is the latest release from the
	<emphasis>6-STABLE</emphasis> branch; it was released in
	&rel.current.date;. Version <ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel2.current;-RELEASE/">&rel2.current;</ulink>
	is the latest release from the
	<emphasis>5-STABLE</emphasis> branch; it was released in
	&rel2.current.date;.</para>

	<para>Briefly, <emphasis>-STABLE</emphasis> is aimed at the
	ISP, corporate user, or any user who wants stability and a
	minimal number of changes compared to the new (and
	possibly unstable) features of the latest
	<emphasis>-CURRENT</emphasis> snapshot. Releases can come
	from either branch, but <emphasis>-CURRENT</emphasis>
	should only be used if you are prepared for its increased
	volatility (relative to <emphasis>-STABLE</emphasis>, that
	is).</para>

	<para>Releases are made <link linkend="release-freq">every
	few months</link>. While many people stay more up-to-date with
	the FreeBSD sources (see the questions on <link
	linkend="current">&os.current;</link> and <link
	linkend="stable">&os.stable;</link>) than that, doing so
	is more of a commitment, as the sources are a moving
	target.</para>

	<para>More information on FreeBSD releases can be found on
	the <ulink
	url="http://www.FreeBSD.org/releng/index.html">Release
	Engineering page</ulink> on the FreeBSD Web site.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="current">
	<para>What is FreeBSD-CURRENT?</para>
	</question>

	<answer>
	<para><ulink
	url="&url.books.handbook;/cutting-edge.html#CURRENT">&os.current;</ulink>
	is the development version of the operating system, which
	will in due course become the new &os.stable; branch.
	As such, it is
	really only of interest to developers working on the
	system and die-hard hobbyists. See the <ulink
	url="&url.books.handbook;/cutting-edge.html#CURRENT">relevant
	section</ulink> in the <ulink
	url="&url.books.handbook;/index.html">handbook</ulink> for details
	on running -CURRENT.</para>

	<para>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
	&os.current;. This branch sometimes evolves quite quickly
	and can be un-buildable for a number of days at a time.
	People that use &os.current; are expected to be able to
	analyze any problems and only report them if they are deemed
	to be mistakes rather than <quote>glitches</quote>. Questions
	such as <quote>make world produces some error about
	groups</quote> on the -CURRENT mailing list may be
	treated with contempt.</para>

	<para>Every day, <ulink
	url="&url.base;/snapshots/">snapshot
	</ulink> releases are made based on the current state of the
	-CURRENT and -STABLE branches. Distributions of the
	occasional snapshot are made available. The goals
	behind each snapshot release are:</para>

	<itemizedlist>
	<listitem>
	<para>To test the latest version of the installation
	software.</para>
	</listitem>

	<listitem>
	<para>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.</para>
	</listitem>

	<listitem>
	<para>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 :)</para>
	</listitem>

	<listitem>
	<para>To ensure that all new features and fixes in need
	of testing have the greatest possible number of
	potential testers.</para>
	</listitem>
	</itemizedlist>

	<para>No claims are made that any -CURRENT snapshot can be
	considered <quote>production quality</quote> 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.</para>

	<para>Snapshot releases are directly available from <ulink
	url="&url.base;/snapshots/">snapshot</ulink>.</para>

	<para>Snapshots are generated, on the average, daily for
	all actively developed branches.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="stable">
	<para>What is the FreeBSD-STABLE concept?</para>
	</question>

	<answer>
	<para>Back when FreeBSD 2.0.5 was released, FreeBSD
	development branched in two. One branch was named <ulink
	url="&url.books.handbook;/current-stable.html#STABLE">-STABLE</ulink>,
	one <ulink
	url="&url.books.handbook;/current-stable.html#CURRENT">-CURRENT</ulink>.
	FreeBSD-STABLE is intended for Internet Service Providers
	and other commercial enterprises for whom sudden shifts or
	experimental features are quite undesirable. It receives
	only well-tested bug fixes and other small incremental
	enhancements. FreeBSD-CURRENT, on the other hand, has
	been one unbroken line since 2.0 was released, leading
	towards 6.2-RELEASE and beyond. Just before 6.0-RELEASE, the
	6-STABLE branch was created, and
	&os.current; became 7-CURRENT. For more detailed information,
	see <quote><ulink url="&url.articles.releng;/release-proc.html#REL-BRANCH">
	FreeBSD Release Engineering:
	Creating the Release Branch</ulink></quote>.</para>

	<para>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 4-STABLE branch has ended with the release
	of 4.11, the final 4.X release. The only changes made to either
	of these branches will be, for the most part, security-related bug
	fixes. Support for the 5-STABLE branches will continue for some
	time but focus primarily on security-related bug fixes and other
	serious issues.</para>

	<para>&rel.current;-STABLE is the actively developed -STABLE branch.
	The latest release on the &rel.current;-STABLE branch is
	&rel.current;-RELEASE, which was released in
	&rel.current.date;.</para>

	<para>The 7-CURRENT branch is the actively developed
	-CURRENT branch toward the next generation of &os;.
	See <link linkend="current">What is &os;-CURRENT?</link> for more
	information on this branch.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="release-freq">
	<para>When are FreeBSD releases made?</para>
	</question>

	<answer>
	<para>The &a.re; releases a new version of FreeBSD about every
	four months, on average. Release dates are announced well in
	advance, so that the people working on the system know
	when their projects need to be finished and tested.
	A testing period precedes each release, in order to ensure
	that the addition of new features does not compromise the
	stability of the release.
	Many users regard this caution as one of the best things about
	FreeBSD, even though waiting for all the latest goodies to reach
	-STABLE can be a little frustrating.</para>

	<para>More information on the release engineering process
	(including a schedule of upcoming releases) can be found
	on the <ulink
	url="http://www.FreeBSD.org/releng/index.html">release
	engineering</ulink> pages on the FreeBSD Web site.</para>

	<para>For people who need or want a little more excitement,
	binary snapshots are made daily as discussed above.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="responsible">
	<para>Who is responsible for FreeBSD?</para>
	</question>

	<answer>
	<para>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 <ulink
	url="&url.base;/administration.html#t-core">core
	team</ulink> of 9 people. There is a much larger team of
	more than 350 <ulink
	url="&url.articles.contributors;/article.html#STAFF-COMMITTERS">committers</ulink>
	who are authorized to make changes directly to the FreeBSD
	source tree.</para>

	<para>However, most non-trivial changes are discussed in advance
	in the <link linkend="mailing">mailing lists</link>, and there
	are no restrictions on who may take part in the
	discussion.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="where-get">
	<para>Where can I get FreeBSD?</para>
	</question>

	<answer>
	<para>Every significant release of FreeBSD is available via
	anonymous FTP from the <ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/">
	FreeBSD FTP site</ulink>:</para>

	<itemizedlist>
	<listitem>
	<para>The latest 6-STABLE release, &rel.current;-RELEASE can be
	found in the <ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel.current;-RELEASE/">&rel.current;-RELEASE directory</ulink>.</para>
	</listitem>

	<listitem>
	<para><ulink
	url="&url.base;/snapshots/">
	Snapshot</ulink> releases are made daily for the
	<link linkend="current">-CURRENT</link> and <link
	linkend="stable">-STABLE</link> branch, these being
	of service purely to bleeding-edge testers and
	developers.</para>
	</listitem>

	<listitem>
	<para>The latest 5-STABLE release, &rel2.current;-RELEASE can be
	found in the <ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel2.current;-RELEASE/">&rel2.current;-RELEASE directory</ulink>.</para>
	</listitem>
	</itemizedlist>

	<para>Information about obtaining FreeBSD on CD, DVD, and other
	media can be found in <ulink url="&url.books.handbook;/mirrors.html">the
	Handbook</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="access-pr">
	<para>How do I access the Problem Report database?</para>
	</question>

	<answer>
	<para>The Problem Report database of all user change requests
	may be queried by using our web-based PR
	<ulink
	url="http://www.FreeBSD.org/cgi/query-pr-summary.cgi?query">
	query</ulink>
	interface.</para>

	<para>The &man.send-pr.1; command can be used to submit problem
	reports and change requests via electronic mail. Alternatively,
	the <ulink url="http://www.freebsd.org/send-pr.html">web-based
	problem report submission interface</ulink> can be used to submit
	problem reports through a web browser.</para>

	<para>Before submitting a problem report, please read <ulink
	url="&url.articles.problem-reports;/article.html">Writing
	FreeBSD Problem Reports</ulink>, an article on how to write
	good problem reports.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="other-info-sources">
	<para>What other sources of information are there?</para>
	</question>

	<answer>
	<para>Please check the <ulink
	url="http://www.FreeBSD.org/docs.html">Documentation</ulink>
	list on the main <ulink
	url="http://www.FreeBSD.org">FreeBSD</ulink> web
	site.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="support">
	<title>Documentation and Support</title>

	<qandaset>
	<qandaentry>
	<question id="books">
	<para>What good books are there about FreeBSD?</para>
	</question>

	<answer>
	<para>The project produces a wide range of documentation,
	available online from this link: <ulink
	url="http://www.FreeBSD.org/docs.html"></ulink>. The same
	documents are available as packages, that you can easily
	install on your FreeBSD system. More details on
	documentation packages can be found in the next
	paragraphs.</para>

	<para>In addition, the Bibliography at the end of this
	FAQ, and the one in the Handbook reference other
	recommended books.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="doc-formats">
	<para>Is the documentation available in other formats, such as plain
	text (ASCII), or &postscript;?</para>
	</question>

	<answer>
	<para>Yes. The documentation is available in a number of
	different formats and compression schemes on the FreeBSD
	FTP site, in the <ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/">/pub/FreeBSD/doc/</ulink>
	directory.</para>

	<para>The documentation is categorized in a number of different
	ways. These include:</para>

	<itemizedlist>
	<listitem>
	<para>The document's name, such as <literal>faq</literal>, or
	<literal>handbook</literal>.</para>
	</listitem>

	<listitem>
	<para>The document's language and encoding. These are
	based on the locale names you will find under
	<filename>/usr/share/locale</filename> on your FreeBSD
	system. The current languages and encodings that we
	have for documentation are as follows:</para>

	<informaltable frame="none" pgwide="1">
	<tgroup cols="2">
	<thead>
	<row>
	<entry>Name</entry>

	<entry>Meaning</entry>
	</row>
	</thead>

	<tbody>
	<row>
	<entry><literal>en_US.ISO8859-1</literal></entry>

	<entry>US English</entry>
	</row>

	<row>
	<entry><literal>bn_BD.ISO10646-1</literal></entry>

	<entry>Bengali (or Bangla)</entry>
	</row>

	<row>
	<entry><literal>da_DK.ISO8859-1</literal></entry>

	<entry>Danish (Denmark)</entry>
	</row>

	<row>
	<entry><literal>de_DE.ISO8859-1</literal></entry>

	<entry>German</entry>
	</row>

	<row>
	<entry><literal>el_GR.ISO8859-7</literal></entry>

	<entry>Greek (Greece)</entry>
	</row>

	<row>
	<entry><literal>es_ES.ISO8859-1</literal></entry>

	<entry>Spanish</entry>
	</row>

	<row>
	<entry><literal>fr_FR.ISO8859-1</literal></entry>

	<entry>French</entry>
	</row>

	<row>
	<entry><literal>hu_HU.ISO8859-2</literal></entry>

	<entry>Hungarian</entry>
	</row>

	<row>
	<entry><literal>it_IT.ISO8859-15</literal></entry>

	<entry>Italian</entry>
	</row>

	<row>
	<entry><literal>ja_JP.eucJP</literal></entry>

	<entry>Japanese (EUC encoding)</entry>
	</row>

	<row>
	<entry><literal>mn_MN.UTF-8</literal></entry>

	<entry>Mongolian (UTF-8 encoding)</entry>
	</row>

	<row>
	<entry><literal>nl_NL.ISO8859-1</literal></entry>

	<entry>Dutch (Netherlands)</entry>
	</row>

	<row>
	<entry><literal>no_NO.ISO8859-1</literal></entry>

	<entry>Norwegian (Norway)</entry>
	</row>

	<row>
	<entry><literal>pl_PL.ISO8859-2</literal></entry>

	<entry>Polish (Poland)</entry>
	</row>

	<row>
	<entry><literal>pt_BR.ISO8859-1</literal></entry>

	<entry>Portuguese (Brazil)</entry>
	</row>

	<row>
	<entry><literal>ru_RU.KOI8-R</literal></entry>

	<entry>Russian (KOI8-R encoding)</entry>
	</row>

	<row>
	<entry><literal>sr_YU.ISO8859-2</literal></entry>

	<entry>Serbian (Serbia)</entry>
	</row>

	<row>
	<entry><literal>tr_TR.ISO8859-9</literal></entry>

	<entry>Turkish (Turkey)</entry>
	</row>

	<row>
	<entry><literal>zh_CN.GB2312</literal></entry>

	<entry>Simplified Chinese (GB2312 encoding)</entry>
	</row>

	<row>
	<entry><literal>zh_TW.Big5</literal></entry>

	<entry>Traditional Chinese (Big5 encoding)</entry>
	</row>
	</tbody>
	</tgroup>
	</informaltable>

	<note>
	<para>Some documents may not be available in all
	languages.</para>
	</note>
	</listitem>

	<listitem>
	<para>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:</para>

	<informaltable frame="none" pgwide="1">
	<tgroup cols="2">
	<thead>
	<row>
	<entry>Format</entry>

	<entry>Meaning</entry>
	</row>
	</thead>

	<tbody>
	<row>
	<entry><literal>html-split</literal></entry>

	<entry>A collection of small, linked, HTML
	files.</entry>
	</row>

	<row>
	<entry><literal>html</literal></entry>

	<entry>One large HTML file containing the entire
	document</entry>
	</row>

	<row>
	<entry><literal>pdb</literal></entry>

	<entry>Palm Pilot database format, for use with the
	<ulink url="http://www.iSilo.com/">iSilo</ulink>
	reader.</entry>
	</row>

	<row>
	<entry><literal>pdf</literal></entry>

	<entry>Adobe's Portable Document Format</entry>
	</row>

	<row>
	<entry><literal>ps</literal></entry>

	<entry>&postscript;</entry>
	</row>

	<row>
	<entry><literal>rtf</literal></entry>

	<entry>Microsoft's Rich Text Format<footnote>
	<para>Page numbers are not automatically
	updated when loading this format into Word.
	Press <keycombo
	action="simul"><keycap>CTRL</keycap><keycap>A</keycap></keycombo>,
	<keycombo
	action="simul"><keycap>CTRL</keycap><keycap>END</keycap></keycombo>,
	<keycap>F9</keycap> after loading the
	document, to update the page numbers.</para>
	</footnote>
	</entry>
	</row>

	<row>
	<entry><literal>txt</literal></entry>

	<entry>Plain text</entry>
	</row>
	</tbody>
	</tgroup>
	</informaltable>
	</listitem>

	<listitem>
	<para>The compression and packaging scheme. There are three of
	these currently in use.</para>

	<orderedlist>
	<listitem>
	<para>Where the format is
	<literal>html-split</literal>, the files are
	bundled up using &man.tar.1;. The resulting
	<filename>.tar</filename> file is then compressed
	using the compression schemes detailed in the next
	point.</para>
	</listitem>

	<listitem>
	<para>All the other formats generate one file,
	called
	<filename><replaceable>type</replaceable>.<replaceable>format</replaceable></filename>
	(i.e., <filename>article.pdf</filename>,
	<filename>book.html</filename>, and so on).</para>

	<para>These files are then compressed using two
	compression schemes.</para>

	<informaltable frame="none" pgwide="1">
	<tgroup cols="2">
	<thead>
	<row>
	<entry>Scheme</entry>

	<entry>Description</entry>
	</row>
	</thead>

	<tbody>
	<row>
	<entry><literal>zip</literal></entry>

	<entry>The Zip format. If you want to
	uncompress this on FreeBSD you will need
	to install the <filename
	role="package">archivers/unzip</filename>
	port first.</entry>
	</row>

	<row>
	<entry><literal>bz2</literal></entry>

	<entry>The BZip2 format. Less widespread
	than Zip, but generally gives
	smaller files. Install the <filename
	role="package">archivers/bzip2</filename>
	port to uncompress these files.</entry>
	</row>
	</tbody>
	</tgroup>
	</informaltable>

	<para>So the &postscript; version of the Handbook,
	compressed using BZip2 will be stored in a file
	called <filename>book.ps.bz2</filename> in the
	<filename>handbook/</filename> directory.</para>
	</listitem>
	</orderedlist>
	</listitem>
	</itemizedlist>

	<para>After choosing the format and compression mechanism that you
	want to download, you will have to
	download the compressed files yourself, uncompress them, and then
	copy the appropriate documents into place.</para>

	<para>For example, the split HTML version of the FAQ,
	compressed using &man.bzip2.1;, can be found in the
	<filename>doc/en_US.ISO8859-1/books/faq/book.html-split.tar.bz2</filename>
	file. To download and uncompress that file you would have
	to do this.</para>

	<screen>&prompt.root; <userinput>fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/en_US.ISO8859-1/books/faq/book.html-split.tar.bz2</userinput>
	&prompt.root; <userinput>bzip2 -d book.html-split.tar.bz2</userinput>
	&prompt.root; <userinput>tar xvf book.html-split.tar</userinput></screen>

	<para>You will be left with a collection of
	<filename>.html</filename> files. The main one is called
	<filename>index.html</filename>, 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mailing">
	<para>Where do I find info on the FreeBSD mailing lists?</para>
	</question>

	<answer>
	<para>You can find full information in the <ulink
	url="&url.books.handbook;/eresources.html#ERESOURCES-MAIL">Handbook
	entry on mailing-lists</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="newsgroups">
	<para>What FreeBSD news groups are available?</para>
	</question>

	<answer>
	<para>You can find full information in the <ulink
	url="&url.books.handbook;/eresources-news.html">Handbook entry on
	newsgroups</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="irc">
	<para>Are there FreeBSD IRC (Internet Relay Chat)
	channels?</para>
	</question>

	<answer>
	<para>Yes, most major IRC networks host a FreeBSD chat
	channel:</para>

	<itemizedlist>
	<listitem>
	<para>Channel <literal>#FreeBSD</literal> on
	<ulink url="http://www.efnet.org/index.php">EFNet</ulink>
	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 manual 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 <hostid>irc.chat.org</hostid>.</para>
	</listitem>

	<listitem>
	<para>Channel <literal>#FreeBSDhelp</literal> on
	<ulink url="http://www.efnet.org/index.php">EFNet</ulink>
	is a channel dedicated to helping FreeBSD users. They
	are much more sympathetic to questions than
	<literal>#FreeBSD</literal> is.</para>
	</listitem>

	<listitem>
	<para>Channel <literal>##FreeBSD</literal> on
	<ulink url="http://freenode.net/">Freenode</ulink>
	is a general help channel with about 300 users at any time.
	The conversations have been known to run off-topic for a while,
	but priority is given to users with FreeBSD questions. We are
	good about helping you understand the basics, referring to the
	Handbook whenever possible, and directing you where to learn
	more about the topic you need help with. We are a primarily
	English speaking channel, though we have users from all over
	the world. If you would like to speak in your native language,
	try to ask the question in English and then relocate to another
	channel <literal>##freebsd-<replaceable>lang</replaceable></literal> as
	appropriate.</para>
	</listitem>

	<listitem>
	<para>Channel <literal>#FreeBSD</literal> on
	<ulink url="http://www.dal.net/">DALNET</ulink>
	is available at <hostid>irc.dal.net</hostid> in the
	US and <hostid>irc.eu.dal.net</hostid> in Europe.</para>
	</listitem>

	<listitem>
	<para>Channel <literal>#FreeBSDHelp</literal> on
	<ulink url="http://www.dal.net/">DALNET</ulink>
	is available at <hostid>irc.dal.net</hostid> in the
	US and <hostid>irc.eu.dal.net</hostid> in Europe.</para>
	</listitem>

	<listitem>
	<para>Channel <literal>#FreeBSD</literal> on
	<ulink url="http://www.undernet.org/">UNDERNET</ulink>
	is available at <hostid>us.undernet.org</hostid>
	in the US and <hostid>eu.undernet.org</hostid> in Europe.
	Since it is a help channel, be prepared to read the
	documents you are referred to.</para>
	</listitem>

	<listitem>
	<para>Channel <literal>#FreeBSD</literal> on
	<ulink url="http://www.rusnet.org.ru/">RUSNET</ulink>
	is a russian-language oriented channel dedicated
	to helping &os; users. This is also good place
	for non-technical discussions.</para>
	</listitem>

	<listitem>
	<para>Channel <literal>#bsdchat</literal> on
	<ulink url="http://freenode.net/">Freenode</ulink>
	is a Traditional-Chinese (UTF-8 encoding) language oriented channel dedicated
	to helping &os; users. This is also good place
	for non-technical discussions.</para>
	</listitem>
	</itemizedlist>

	<para>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 <emphasis>all</emphasis> 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="training">
	<para>Where can I get commercial FreeBSD training and support?</para>
	</question>

	<answer>
	<para>DaemonNews provides commercial training and support for
	FreeBSD. More information can be found at their
	<ulink url="http://www.bsdmall.com/">BSD Mall</ulink>
	site.</para>

	<para>The FreeBSD Mall provides commercial FreeBSD support.
	You can get more information at their <ulink
	url="http://www.freebsdmall.com/">web site</ulink>.</para>

	<para>Any other organizations providing training and support should
	contact the project in order to be listed here.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter
	id="install">
	<chapterinfo>
	<author>
	<firstname>Nik</firstname>
	<surname>Clayton</surname>
	<affiliation>
	<address><email>nik@FreeBSD.org</email></address>
	</affiliation>
	</author>
	</chapterinfo>

	<title>Installation</title>

	<qandaset>
	<qandaentry>
	<question id="floppy-download">
	<para>Which file do I download to get FreeBSD?</para>
	</question>

	<answer>
	<para>You need three floppy images:
	<filename>floppies/boot.flp</filename>,
	<filename>floppies/kern1.flp</filename>, and
	<filename>floppies/kern2.flp</filename>. These images need to
	be copied onto floppies by tools like
	<command>fdimage</command> or &man.dd.1;.</para>

	<para>If you need to download the distributions yourself (for a
	DOS filesystem install, for instance), below are some
	recommendations for distributions to grab:</para>


	<itemizedlist>
	<listitem>
	<para>base/</para>
	</listitem>

	<listitem>
	<para>manpages/</para>
	</listitem>

	<listitem>
	<para>compat*/</para>
	</listitem>

	<listitem>
	<para>doc/</para>
	</listitem>

	<listitem>
	<para>src/ssys.*</para>
	</listitem>
	</itemizedlist>


	<para>Full instructions on this procedure and a little bit more
	about installation issues in general can be found in the
	<ulink url="&url.books.handbook;/install.html">Handbook entry on
	installing FreeBSD</ulink>.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="floppy-image-too-large">
	<para>What do I do if the floppy images does not fit on a single
	floppy?</para>
	</question>

	<answer>
	<para>A 3.5 inch (1.44MB) floppy can accommodate 1474560 bytes
	of data. The boot image is exactly 1474560 bytes in size.</para>

	<para>Common mistakes when preparing the boot floppy are:</para>

	<itemizedlist>
	<listitem>
	<para>Not downloading the floppy image in
	<emphasis>binary</emphasis> mode when using
	<acronym>FTP</acronym>.</para>


	<para>Some FTP clients default their transfer mode to
	<emphasis>ascii</emphasis> 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 <emphasis>exactly</emphasis> that
	on the server, then the download process is suspect.</para>

	<para>To workaround: type <emphasis>binary</emphasis> at the
	FTP command prompt after getting connected to the server
	and before starting the download of the image.</para>
	</listitem>

	<listitem>
	<para>Using the DOS <command>copy</command> command (or
	equivalent GUI tool) to transfer the boot image to
	floppy.</para>

	<para>Programs like <command>copy</command> 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
	<quote>raw</quote>, using the low-level tools (e.g.
	<command>fdimage</command> or <command>rawrite</command>)
	described in the <ulink
	url="&url.books.handbook;/install.html">installation guide to
	FreeBSD</ulink>.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="install-instructions-location">
	<para>Where are the instructions for installing FreeBSD?</para>
	</question>

	<answer>
	<para>Installation instructions can be found in the
	<ulink url="&url.books.handbook;/install.html">Handbook entry on installing FreeBSD</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="need-to-run">
	<para>What do I need in order to run FreeBSD?</para>
	</question>

	<answer>
	<para>For &os; 5.X and later you will need a 486 or better
	PC, with 24 MB or more of RAM and at least 150 MB of hard disk
	space.</para>

	<para>All versions of &os; can run with a low
	end MDA graphics card but to run &xorg;, a VGA or better video
	card is needed.</para>

	<para>See also <xref linkend="hardware">.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="custom-boot-floppy">
	<para>How can I make my own custom install floppy?</para>
	</question>

	<answer>
	<para>Currently there is no way to <emphasis>just</emphasis>
	make a custom install floppy. You have to cut a whole new
	release, which will include your install floppy.</para>

	<para>To make a custom release, follow the instructions in the
	<ulink url="&url.articles.releng;/article.html">Release
	Engineering</ulink> article.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="multiboot">
	<para>Can I have more than one operating system on my PC?</para>
	</question>

	<answer>
	<para>Have a look at
	<ulink url="&url.articles.multi-os;/index.html">
	the multi-OS page</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="windows-coexist">
	<para>Can &windows; co-exist with FreeBSD?</para>
	</question>

	<answer>
	<para>Install &windows; first, then FreeBSD.
	FreeBSD's boot manager will then manage to boot &windows; and
	FreeBSD. If you install &windows; second, it will boorishly
	overwrite your boot manager without even asking. If that
	happens, see the next section.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="win95-damaged-boot-manager">
	<para>&windows; killed my boot manager!
	How do I get it back?</para>
	</question>

	<answer>
	<para>You can reinstall the boot manager FreeBSD comes with in
	one of three ways:</para>

	<itemizedlist>
	<listitem>
	<para>Running DOS, go into the tools/ directory of your
	FreeBSD distribution and look for
	<filename>bootinst.exe</filename>. You run it like
	so:</para>

	<screen><prompt>...\TOOLS></prompt> <userinput>bootinst.exe boot.bin</userinput></screen>

	<para>and the boot manager will be reinstalled.</para>
	</listitem>

	<listitem>
	<para>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 <quote>Boot Manager</quote>. This will
	re-write the boot manager to disk. Now quit out of the
	installation menu and reboot off the hard disk as
	normal.</para>
	</listitem>

	<listitem>
	<para>Boot the FreeBSD boot floppy (or CDROM) and choose the
	<quote>Fixit</quote> menu item. Select either the Fixit
	floppy or CDROM #2 (the <quote>live</quote> filesystem
	option) as appropriate and enter the fixit shell. Then
	execute the following command:</para>

	<screen><prompt>Fixit#</prompt> <userinput>fdisk -B -b /boot/boot0 <replaceable>bootdevice</replaceable></userinput></screen>

	<para>substituting <replaceable>bootdevice</replaceable> for
	your real
	boot device such as <devicename>ad0</devicename> (first IDE
	disk), <devicename>ad4</devicename> (first IDE disk on
	auxiliary controller), <devicename>da0</devicename> (first
	SCSI disk), etc.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="boot-on-thinkpad">
	<para>My A, T, or X series IBM Thinkpad locks up when I first
	booted up my FreeBSD installation. How can I solve this?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>According to IBM<footnote><para>In an e-mail from Keith
	Frechette
	<email>kfrechet@us.ibm.com</email>.</para></footnote>, the
	following model/BIOS release numbers incorporate the fix.</para>

	<informaltable frame="none" pgwide="1">
	<tgroup cols="2">
	<thead>
	<row>
	<entry>Model</entry>
	<entry>BIOS revision</entry>
	</row>
	</thead>

	<tbody>
	<row>
	<entry>T20</entry>
	<entry>IYET49WW or later</entry>
	</row>

	<row>
	<entry>T21</entry>
	<entry>KZET22WW or later</entry>
	</row>

	<row>
	<entry>A20p</entry>
	<entry>IVET62WW or later</entry>
	</row>

	<row>
	<entry>A20m</entry>
	<entry>IWET54WW or later</entry>
	</row>

	<row>
	<entry>A21p</entry>
	<entry>KYET27WW or later</entry>
	</row>

	<row>
	<entry>A21m</entry>
	<entry>KXET24WW or later</entry>
	</row>

	<row>
	<entry>A21e</entry>
	<entry>KUET30WW</entry>
	</row>
	</tbody>
	</tgroup>
	</informaltable>

	<para>It has been reported that later IBM BIOS revisions may
	have reintroduced the bug. <ulink
	url="http://docs.FreeBSD.org/cgi/mid.cgi?20010427133759.A71732">This
	message</ulink> 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.</para>

	<para>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.</para>

	<para>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.</para>

	<para>With the machine functional again, you can use the workaround
	procedure described here to get a working FreeBSD
	installation.</para>

	<procedure>
	<step>
	<para>Download <filename>boot1</filename> and
	<filename>boot2</filename> from <ulink
	url="http://people.FreeBSD.org/~bmah/ThinkPad/"></ulink>.
	Put these files somewhere you will be able to retrieve them
	later.</para>
	</step>

	<step>
	<para>Install FreeBSD as normal on to the ThinkPad.
	<emphasis>Do not</emphasis> use <literal>Dangerously
	Dedicated</literal> mode. <emphasis>Do not</emphasis>
	reboot when the install has finished.</para>
	</step>

	<step>
	<para>Either switch to the <quote>Emergency Holographic
	Shell</quote> (<keycombo action="simul"><keycap>ALT</keycap>
	<keycap>F4</keycap></keycombo>) or start a
	<quote>fixit</quote> shell.</para>
	</step>

	<step>
	<para>Use &man.fdisk.8; to change the FreeBSD partition ID from
	<literal>165</literal> to <literal>166</literal> (this is the
	type used by OpenBSD).</para>
	</step>

	<step>
	<para>Bring the <filename>boot1</filename> and
	<filename>boot2</filename> files to the local
	filesystem.</para>
	</step>

	<step>
	<para>Use &man.disklabel.8; to write <filename>boot1</filename>
	and <filename>boot2</filename> to your FreeBSD slice.</para>

	<screen>&prompt.root; <userinput>disklabel -B -b boot1 -s boot2 ad0s<replaceable>n</replaceable></userinput></screen>

	<para><replaceable>n</replaceable> is the number of the slice
	where you installed FreeBSD.</para>
	</step>

	<step>
	<para>Reboot. At the boot prompt you will be given the option
	of booting <literal>OpenBSD</literal>. This will actually
	boot FreeBSD.</para>
	</step>
	</procedure>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="install-bad-blocks">
	<para>Can I install on a disk with bad blocks?</para>
	</question>

	<answer>
	<para>You can, but it is a bad idea.</para>

	<para>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.</para>

	<para>If you have a SCSI drive with bad blocks, see
	<link linkend="awre">this answer</link>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="boot-floppy-strangeness">
	<para>Strange things happen when I boot the install floppy!
	What is happening?</para>
	</question>

	<answer>
	<para>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:</para>

	<orderedlist>
	<listitem>
	<para>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)?</para>
	</listitem>

	<listitem>
	<para>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!)</para>
	</listitem>

	<listitem>
	<para>If you are using &windows; 95 or 98 did you run
	<command>fdimage</command> or
	<command>rawrite</command> 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.</para>
	</listitem>
	</orderedlist>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="no-install-cdrom">
	<para>I booted from my ATAPI CDROM, but the install program
	says no CDROM is found. Where did it go?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="install-PLIP">
	<para>Can I install on my laptop over PLIP (Parallel Line
	IP)?</para>
	</question>

	<answer>
	<para>Yes. Use a standard Laplink cable. If necessary, you
	can check out the <ulink url="&url.books.handbook;/network-plip.html">PLIP
	section of the Handbook</ulink> for details on parallel
	port networking.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="geometry">
	<para>Which geometry should I use for a disk drive?</para>
	</question>

	<answer>
	<note>
	<para>By the <quote>geometry</quote> 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.</para>
	</note>

	<para>This causes a lot of confusion among new system
	administrators. First of all, the
	<emphasis>physical</emphasis> geometry of a SCSI drive is
	totally irrelevant, as FreeBSD works in term of disk
	blocks. In fact, there is no such thing as
	<quote>the</quote> physical geometry, as the sector
	density varies across the disk. What manufacturers claim
	is the <quote>physical geometry</quote> 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.</para>

	<para>All that matters is the <emphasis>logical</emphasis>
	geometry. This is the answer that the BIOS gets when it
	asks the drive <quote>what is your geometry?</quote> 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!</para>

	<para>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 <quote>support for
	DOS disks >1GB</quote> or something similar). If it is
	turned off, then use <replaceable>N</replaceable>
	cylinders, 64 heads and 32 sectors/track, where
	<replaceable>N</replaceable> 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.</para>

	<para>If it <emphasis>is</emphasis> turned on (it is often
	supplied this way to get around certain limitations in
	&ms-dos;) and the disk capacity is more than 1GB, use <replaceable>M</replaceable>
	cylinders, 63 sectors per track (<emphasis>not</emphasis>
	64), and 255 heads, where <replaceable>M</replaceable> 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.</para>

	<para>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.</para>

	<para>Alternatively, there is a freely available utility
	distributed with FreeBSD called
	<filename>pfdisk.exe</filename>. You can find it in the
	<filename>tools</filename> 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="disk-divide-restrictions">
	<para>Are there any restrictions on how I divide the disk up?</para>
	</question>

	<answer>
	<para>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).</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="disk-manager">
	<para>Is FreeBSD compatible with any disk managers?</para>
	</question>

	<answer>
	<para>FreeBSD recognizes the Ontrack Disk Manager and makes
	allowances for it. Other disk managers are not supported.</para>

	<para>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.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="missing-os">
	<para>When I boot FreeBSD for the first time after install I get <errorname>Missing Operating
	System</errorname>. What is happening?</para>
	</question>

	<answer>
	<para>This is classically a case of FreeBSD and DOS or some other
	OS conflicting over their ideas of disk <link
	linkend="geometry">geometry</link>. You will have to reinstall
	FreeBSD, but obeying the instructions given above will almost
	always get you going.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="stop-at-boot-manager">
	<para>Why can I not get past the boot manager's <prompt>F?</prompt>
	prompt?</para>
	</question>

	<answer>
	<para>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 <quote>>1GB drive
	support</quote>), try toggling its setting and reinstalling
	FreeBSD.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="need-complete-sources">
	<para>Do I need to install the complete sources?</para>
	</question>

	<answer>
	<para>In general, no. However, we would strongly recommend that
	you install, at a minimum, the <literal>base</literal> source
	kit, which includes several of the files mentioned here, and
	the <literal>sys</literal> (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
	(due to the kernel-source restriction, we recommend that
	you not mount this on <filename>/usr/src</filename> directly,
	but rather in some other location with appropriate symbolic
	links to duplicate the top-level structure of the source
	tree).</para>

	<para>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.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="need-kernel">
	<para>Do I need to build a kernel?</para>
	</question>

	<answer>
	<para>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 much friendlier kernel
	configuration methods. In &os; 5.X and later, it is very easily
	to configure the kernel's configuration by much more flexible
	"hints" which can be set from the loader prompt.</para>

	<para>It may still be worthwhile building a new
	kernel containing just the drivers that you need, just to save a
	bit of RAM, but it is no longer necessary for most
	systems.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="password-encryption">
	<para>Should I use DES, Blowfish, or MD5 passwords and how
	do I specify which form my users receive?</para>
	</question>

	<answer>
	<para>The default password format on FreeBSD is to use
	<emphasis>MD5</emphasis>-based passwords. These are
	believed to be more secure than the traditional &unix;
	password format, which used a scheme based on the
	<emphasis>DES</emphasis> 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 <quote>crypto</quote> 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
	<quote>passwd_format</quote> login capability in
	<filename>/etc/login.conf</filename>, which takes values
	of <quote>des</quote>, <quote>blf</quote> (if these are
	available) or <quote>md5</quote>. See the
	&man.login.conf.5; manual page for more information about
	login capabilities.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="boot-floppy-hangs">
	<para>Why does the boot floppy start, but hang at the
	<literal>Probing Devices...</literal> screen?</para>
	</question>

	<answer>

	<para>If you have a IDE &iomegazip; 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="panic-on-install-reboot">
	<para>Why do I get a <errorname>panic: can't mount root</errorname>
	error when rebooting the system after installation?</para>
	</question>

	<answer>
	<para>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 <devicename>ad0</devicename> (the second BIOS
	disk) while the kernel assigns the first disk on the
	secondary controller device, <devicename>ad2</devicename>. After the device
	probing, the kernel tries to mount what the boot blocks
	think is the boot disk, <devicename>ad0</devicename>, while it is really <devicename>ad2</devicename>, and
	fails.</para>

	<para>To fix the problem, do one of the following:</para>

	<orderedlist>
	<listitem>
	<para>Reboot the system and hit <keycap>Enter</keycap>
	at the <literal>Booting kernel in 10 seconds; hit
	[Enter] to interrupt</literal> prompt. This will
	drop you into the boot loader.</para>

	<para>Then type
	<userinput>
	set
	root_disk_unit="<replaceable>disk_number</replaceable>"
	</userinput>. <replaceable>disk_number</replaceable>
	will be <literal>0</literal> if FreeBSD is installed
	on the master drive on the first IDE controller,
	<literal>1</literal> if it is installed on the slave
	on the first IDE controller, <literal>2</literal> if
	it is installed on the master of the second IDE
	controller, and <literal>3</literal> if it is
	installed on the slave of the second IDE
	controller.</para>

	<para>Then type <userinput>boot</userinput>, and your
	system should boot correctly.</para>

	<para>To make this change permanent (i.e, so you do not
	have to do this every time you reboot or turn on
	your FreeBSD machine), put the line <userinput>
	root_disk_unit="<replaceable>disk_number</replaceable>"</userinput>
	in <filename>/boot/loader.conf.local
	</filename>.</para>
	</listitem>

	<listitem>
	<para>Move the FreeBSD disk onto the primary IDE
	controller, so the hard disks are
	consecutive.</para>
	</listitem>
	</orderedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="memory-limits">
	<para>What are the limits for memory?</para>
	</question>

	<answer>
	<para>The limit is 4 gigabytes on a standard &i386; install.
	Beginning with &os; versions 4.9 and 5.1, more memory can be
	supported through &man.pae.4;. This does require a kernel
	recompile, with an extra option to enable PAE:</para>

	<programlisting>options PAE</programlisting>

	<para>&os;/pc98 has a limit of 4 GB memory, and PAE can not
	be used with it. Other architectures
	supported by &os; have much higher theoretical limits on
	maximum memory (many terabytes).</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ffs-limits">
	<para>What are the limits for ffs filesystems?</para>
	</question>

	<answer>
	<para>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).</para>

	<para>The maximum size of a single ffs file is approximately 1G
	blocks, or 4TB with a block size of 4K.</para>

	<table>
	<title>Maximum file sizes</title>

	<tgroup cols="3">
	<thead>
	<row>
	<entry>fs block size</entry>

	<entry>works</entry>

	<entry>should work</entry>
	</row>
	</thead>

	<tbody>
	<row>
	<entry>4K</entry>

	<entry>4T-1</entry>

	<entry>>4T</entry>
	</row>

	<row>
	<entry>8K</entry>

	<entry>>32G</entry>

	<entry>32T-1</entry>
	</row>

	<row>
	<entry>16K</entry>

	<entry>>128G</entry>

	<entry>32T-1</entry>
	</row>

	<row>
	<entry>32K</entry>

	<entry>>512G</entry>

	<entry>64T-1</entry>
	</row>

	<row>
	<entry>64K</entry>

	<entry>>2048G</entry>

	<entry>128T-1</entry>
	</row>
	</tbody>
	</tgroup>
	</table>

	<para>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.</para>

	<para>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.
	Using the correct limit of 2G-1 blocks does cause
	problems.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="archsw-readin-failed-error">
	<para>Why do I get an error message,
	<errorname>archsw.readin.failed</errorname> after compiling
	and booting a new kernel?</para>
	</question>

	<answer>
	<para>Because your world and kernel are out of sync. This
	is not supported. Be sure you use <command>make
	<maketarget>buildworld</maketarget></command> and <command>make
	<maketarget>buildkernel</maketarget></command> to update your kernel.</para>

	<para>You can boot by specifying the kernel directly at the
	second stage, pressing any key when the \| shows up before
	loader is started.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="boot-acpi">
	<para>Installation crashes while booting, what can I do?</para>
	</question>

	<answer>
	<para>Try disabling ACPI support. When the bootloader loads, press
	the space key. The system will display the following:</para>

	<screen>OK</screen>

	<para>Type:</para>

	<screen><userinput>unset acpi_load</userinput></screen>

	<para>And then type:</para>

	<screen><userinput>boot</userinput></screen>
	</answer>
	</qandaentry>

	</qandaset>
	</chapter>

	<chapter
	id="hardware">
	<title>Hardware compatibility</title>

	<sect1 id="compatibility-general">
	<title>General</title>

	<qandaset>
	<qandaentry>
	<question id="which-hardware-to-get">
	<para>I want to get a piece of hardware for my FreeBSD
	system. Which model/brand/type is best?</para>
	</question>

	<answer>
	<para>This is discussed continually on the FreeBSD mailing
	lists. Since hardware changes so quickly, however, we
	expect this. We <emphasis>still</emphasis> strongly
	recommend that you read through the Hardware notes for &os;
	<ulink url="&rel.current.hardware;">&rel.current;</ulink>
	or
	<ulink url="&rel2.current.hardware;">&rel2.current;</ulink>
	and search the mailing list
	<ulink url="http://www.FreeBSD.org/search/#mailinglists">
	archives</ulink> 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.</para>

	<para>If you are looking for a laptop, check the
	&a.mobile; archives. Otherwise, you
	probably want the archives for the &a.questions;, or
	possibly a specific mailing list for a particular hardware
	type.</para>
	</answer>
	</qandaentry>

	</qandaset>
	</sect1>

	<sect1 id="compatibility-processors">
	<title>Architectures and processors</title>

	<qandaset>
	<qandaentry>
	<question id="architectures">
	<para>Does FreeBSD support architectures other than the x86?</para>
	</question>

	<answer>

	<para>Yes. FreeBSD currently runs on the Intel x86 and the AMD64
	architectures. The Intel EM64T, IA-64, &arm;, &powerpc;, sun4v and
	&sparc64; architectures are also supported. Upcoming platforms are
	&mips; and &s390;, join the &a.mips; for more information about
	ongoing work on the &mips; platform. For general discussion on
	new architectures, join the &a.platforms;.</para>

	<para>If your machine has a different architecture and you
	need something right now, we suggest you look at <ulink
	url="http://www.netbsd.org/">NetBSD</ulink> or <ulink
	url="http://www.openbsd.org/">OpenBSD</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="smp-support">
	<para>Does FreeBSD support Symmetric Multiprocessing
	(SMP)?</para>
	</question>

	<answer>
	<para>Yes. SMP was enabled by default in the
	<emphasis>GENERIC</emphasis> kernel as of &os; 5.2.</para>

	<para>The intention was also to enable it by default for
	the &os; 5.3 release, but problems running the SMP kernel
	on certain UP machines led to the decision to disable it
	until those problems can be addressed. This is a priority
	for &os; 5.4.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</sect1>

	<sect1 id="compatibility-drives">
	<title>Hard drives, tape drives, and CD and DVD drives</title>

	<qandaset>

	<qandaentry>
	<question id="supported-hard-drives">
	<para>What kind of hard drives does FreeBSD support?</para>
	</question>

	<answer>
	<para>FreeBSD supports EIDE, SATA, SCSI, and SAS drives (with a
	compatible controller; see the next section), and all drives using
	the original <quote>Western Digital</quote> 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="supported-scsi-controllers">
	<para>Which SCSI or SAS controllers are supported?</para>
	</question>

	<answer>
	<para>See the complete list in the Hardware Notes for &os;
	<ulink url="&rel.current.hardware;">&rel.current;</ulink> or
	<ulink url="&rel2.current.hardware;">&rel2.current;</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="tape-support">
	<para>What types of tape drives are supported?</para>
	</question>

	<answer>

	<para>FreeBSD supports SCSI and QIC-36 (with a QIC-02 interface).
	This includes 8-mm (aka Exabyte) and DAT drives.</para>

	<para>Some of the early 8-mm drives are not quite compatible
	with SCSI-2, and may not work well with FreeBSD.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="tape-changer-support">
	<para>Does FreeBSD support tape changers?</para>
	</question>

	<answer>
	<para>FreeBSD 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;
	manual page.</para>

	<para>If you are not using <application>AMANDA</application>
	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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="supported-cdrom-drives">
	<para>Which CDROM drives are supported by FreeBSD?</para>
	</question>

	<answer>
	<para>Any SCSI drive connected to a supported controller is
	supported.</para>

	<para>The following proprietary CDROM interfaces are also
	supported:</para>

	<itemizedlist>
	<listitem>
	<para>Mitsumi LU002 (8bit), LU005 (16bit) and FX001D
	(16bit 2x Speed).</para>
	</listitem>

	<listitem>
	<para>Sony CDU 31/33A</para>
	</listitem>

	<listitem>
	<para>Sound Blaster Non-SCSI CDROM</para>
	</listitem>

	<listitem>
	<para>Matsushita/Panasonic CDROM</para>
	</listitem>

	<listitem>
	<para>ATAPI compatible IDE CDROMs</para>
	</listitem>
	</itemizedlist>

	<para>All non-SCSI cards are known to be extremely slow compared
	to SCSI drives, and some ATAPI CDROMs may not work.</para>

	<para>The official FreeBSD CDROM ISO, and CDROMs from Daemon
	News and FreeBSD Mall, support booting directly from the
	CD.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="supported-cdrw-drives">
	<para>Which CD-RW drives are supported by FreeBSD?</para>
	</question>

	<answer>
	<para>FreeBSD supports any ATAPI-compatible IDE CD-R or CD-RW
	drive. See &man.burncd.8; for details.</para>

	<para>FreeBSD also supports any SCSI CD-R or CD-RW drives.
	Install and use the <command>cdrecord</command> command from the
	ports or packages system, and make sure that you have the
	<devicename>pass</devicename> device compiled in your
	kernel.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="zip-support">
	<para>Does FreeBSD support &iomegazip; drives?</para>
	</question>

	<answer>
	<para>FreeBSD supports SCSI and ATAPI (IDE) &iomegazip; drives out
	of the box. SCSI ZIP drives 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.</para>

	<para>FreeBSD also supports Parallel Port Zip Drives. Check
	that your kernel contains the
	<devicename>scbus0</devicename>,
	<devicename>da0</devicename>,
	<devicename>ppbus0</devicename>, and
	<devicename>vp0</devicename> drivers (the GENERIC kernel
	contains everything except
	<devicename>vp0</devicename>). With all these drivers
	present, the Parallel Port drive should be available as
	<devicename>/dev/da0s4</devicename>. Disks can be mounted
	using <command>mount /dev/da0s4 /mnt</command> OR (for dos
	disks) <command>mount_msdos /dev/da0s4 /mnt</command> as
	appropriate.</para>

	<para>Also check out <link linkend="media-change">the FAQ on
	removable drives</link> later in this chapter, and <link
	linkend="removable-drives">the note on
	<quote>formatting</quote></link>in the Administration
	chapter.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="jaz-zip-removable-support">
	<para>Does FreeBSD support &jaz;, EZ and other removable
	drives?</para>
	</question>

	<answer>
	<para>They work. Most of these are SCSI devices, so they
	look like SCSI disks to FreeBSD. The IDE EZ looks like an
	IDE drive.</para>

	<para>Make sure that any external units are powered on when
	booting the system.</para>

	<para><anchor id="media-change">To change the media while
	running, check out &man.mount.8;, &man.umount.8;, and
	&man.camcontrol.8; (for SCSI devices) or
	&man.atacontrol.8; (for IDE devices), plus the <link
	linkend="removable-drives">discussion on using removable
	drives</link> later in the FAQ.</para>
	</answer>
	</qandaentry>

	</qandaset>

	</sect1>

	<sect1 id="compatibility-kbd-mice">
	<title>Keyboards and mice</title>

	<qandaset>

	<qandaentry>
	<question id="usbkbd">
	<para>Does FreeBSD support my USB keyboard?</para>
	</question>

	<answer>
	<para>FreeBSD supports USB keyboards
	out-of-the-box. Enable USB support in
	<filename>/etc/rc.conf</filename>.</para>

	<para>Once you have USB keyboard support enabled on your
	system, the AT keyboard becomes
	<devicename>/dev/kbd0</devicename> and the USB keyboard
	becomes <devicename>/dev/kbd1</devicename>, if both are
	connected to the system. If there is the USB keyboard
	only, it will be
	<devicename>/dev/ukbd0</devicename>.</para>

	<para>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.</para>

	<screen>&prompt.root; <userinput>kbdcontrol -k /dev/kbd1 < /dev/ttyv0 > /dev/null</userinput></screen>

	<para>Note that if the USB keyboard is the only keyboard, it
	is accessed as <devicename>/dev/ukbd0</devicename>, thus,
	the command should look like:</para>

	<screen>&prompt.root; <userinput>kbdcontrol -k /dev/ukbd0 < /dev/ttyv0 > /dev/null</userinput></screen>

	<para><filename>/etc/rc.i386</filename> is a good place to
	add the above command.</para>

	<para>Once this is done, the USB keyboard should work in the
	X environment as well without any special settings.</para>

	<para>Hot-plugging and unplugging of the USB keyboard may
	not work quite right yet. We recommend connecting the
	keyboard before starting the system and leaving it
	connected until the system is shutdown to avoid
	troubles.</para>

	<para>See the &man.ukbd.4; manual page for more information.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="busmouse">
	<para>I have an unusual bus mouse. How do I set it
	up?</para>
	</question>

	<answer>
	<para>FreeBSD supports the bus mouse and the InPort bus
	mouse from such manufacturers as Microsoft, Logitech and
	ATI. The GENERIC kernel does not include the device
	driver. To build a custom kernel with the bus mouse
	driver, add the following line to the kernel config
	file:</para>

	<programlisting>device mse0 at isa? port 0x23c irq5</programlisting>

	<para>Bus mice usually come 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; manual page for more
	information.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ps2mouse">
	<para>How do I use my PS/2 (<quote>mouse port</quote> or
	<quote>keyboard</quote>) mouse?</para>
	</question>

	<answer>
	<para>The PS/2 mouse is supported out-of-the-box. The
	necessary device driver, <devicename>psm</devicename>, is
	included in the kernel.</para>

	<para>If your custom kernel does not have this, add the
	following line to your kernel configuration and compile a
	new kernel.</para>

	<programlisting>device psm0 at atkbdc? irq 12</programlisting>

	<para>Once the kernel detects <devicename>psm0</devicename>
	correctly at boot time, make sure that an entry for
	<devicename>psm0</devicename> exists in
	<filename>/dev</filename>. You can create this entry by
	typing:</para>

	<screen>&prompt.root; <userinput>cd /dev; sh MAKEDEV psm0</userinput></screen>

	<para>when logged in as <username>root</username>.</para>

	<note>
	<para>You can omit this step if you are running FreeBSD
	5.0-RELEASE or newer with &man.devfs.5; enabled,
	since the proper device nodes will be created automatically
	under <filename>/dev</filename>.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="moused">
	<para>Is it possible to use a mouse in any way outside the X
	Window system?</para>
	</question>

	<answer>
	<para>If you are using the default console driver,
	&man.syscons.4;, you can use a mouse pointer in text
	consoles to cut & paste text. Run the mouse daemon,
	&man.moused.8;, and turn on the mouse pointer in the
	virtual console:</para>

	<screen>&prompt.root; <userinput>moused -p /dev/<replaceable>xxxx</replaceable> -t <replaceable>yyyy</replaceable></userinput>
	&prompt.root; <userinput>vidcontrol -m on</userinput></screen>

	<para>Where <replaceable>xxxx</replaceable> is the mouse
	device name and <replaceable>yyyy</replaceable> is a
	protocol type for the mouse. The mouse daemon can
	automatically determine the protocol type of most
	mice, except old serial mice. Specify the
	<literal>auto</literal> protocol to invoke automatic
	detection. If automatic detection does not work, see the
	&man.moused.8; manual page for a list of supported
	protocol types.</para>

	<para>If you have a PS/2 mouse, just add
	<literal>moused_enable="YES"</literal> to
	<filename>/etc/rc.conf</filename> to start the mouse
	daemon at boot-time. Additionally, if you would like to
	use the mouse daemon on all virtual terminals instead of
	just the console, add <literal>allscreens_flags="-m
	on"</literal> to <filename>/etc/rc.conf</filename>.</para>

	<para>When the mouse daemon is running, access to the mouse
	must be coordinated between the mouse daemon and other
	programs such as X Windows. Refer to the FAQ <link
	linkend="x-and-moused">Why does my mouse not work with
	X?</link> for more details on this issue.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="text-mode-cut-paste">
	<para>How do I cut and paste text with a mouse in the text
	console?</para>
	</question>

	<answer>
	<para>Once you get the mouse daemon running (see the <link
	linkend="moused">previous section</link>), hold down the
	button 1 (left button) and move the mouse to select a
	region of text. Then, press the button 2 (middle button)
	to paste it at the text cursor. Pressing button 3 (right
	button) will <quote>extend</quote> the selected region of
	text.</para>

	<para>If your mouse does not have a middle button, you may
	wish to emulate one or remap buttons using mouse daemon
	options. See the &man.moused.8; manual page for
	details.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mouse-wheel-buttons">
	<para>My mouse has a fancy wheel and buttons. Can I use them in
	FreeBSD?</para>
	</question>

	<answer>
	<para>The answer is, unfortunately, <quote>It depends</quote>.
	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.</para>

	<para>For the possible usage of wheels in the X Window
	environment, refer to <link linkend="x-and-wheel">that
	section</link>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="laptop-mouse-trackball">
	<para>How do I use the mouse/trackball/touchpad on my laptop?</para>
	</question>

	<answer>
	<para>Please refer to <link linkend="ps2mouse">the answer to
	the previous question</link>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="keyboard-delete-key">
	<para>How do I use my delete key in <command>sh</command> and
	<command>csh</command>?</para>
	</question>

	<answer>
	<para>For the <application>Bourne Shell</application>, add the
	following lines to your <filename>.shrc</filename>. See &man.sh.1;
	and &man.editrc.5;.</para>

	<programlisting>bind ^? ed-delete-next-char # for console
	bind ^[[3~ ed-delete-next-char # for xterm</programlisting>

	<para>For the <application>C Shell</application>, add the following
	lines to your <filename>.cshrc</filename>. See &man.csh.1;.</para>

	<programlisting>bindkey ^? delete-char # for console
	bindkey ^[[3~ delete-char # for xterm</programlisting>

	<para>For more information, see <ulink
	url="http://www.ibb.net/~anne/keyboard.html">this page</ulink>.
	</para>
	</answer>
	</qandaentry>

	</qandaset>

	</sect1>

	<sect1 id="compatibility-networking">
	<title>Networking and serial devices</title>

	<qandaset>

	<qandaentry>
	<question id="network-cards">
	<para>Which network cards does FreeBSD support?</para>
	</question>

	<answer>
	<para>See the Hardware Notes supplied with each release of
	FreeBSD for a more
	complete list.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="support-winmodem">
	<para>Does FreeBSD support software modems, such as Winmodems?</para>
	</question>

	<answer>
	<para>FreeBSD supports many software modems via add-on
	software. The <filename role="package">comms/ltmdm</filename> port adds
	support for modems based on the very popular Lucent LT
	chipset. The <filename role="package">comms/mwavem</filename> port
	supports the modem in IBM Thinkpad 600 and 700
	laptops.</para>

	<para>You cannot install FreeBSD via a software modem; this
	software must be installed after the OS is
	installed.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="support-broadcom">
	<para>Is there a native driver for the Broadcom 43xx cards?</para>
	</question>

	<answer>
	<para>No, and there is not likely to be.</para>

	<para>Broadcom refuses to publically release programming
	information for their wireless chipsets, most likely because
	they use software controlled radios. In order to get FCC type
	acceptance for their parts, they have to ensure that users
	cannot arbitrarily set things like operating frequencies,
	modulation parameters and power output. But without knowing
	how to program the chipsets, it is nearly impossible to write
	a driver.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="multiport-serial-support">
	<para>Which multi-port serial cards are supported by
	FreeBSD?</para>
	</question>

	<answer>
	<para>There is a list of these in the <ulink
	url="&url.books.handbook;/serial.html">Serial Communications
	</ulink> chapter of the handbook.</para>

	<para>Some unnamed clone cards have also been known to work,
	especially those that claim to be AST compatible.</para>

	<para>Check the &man.sio.4; manual page to get more
	information on configuring such cards.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="serial-console-prompt">
	<para>How do I get the boot: prompt to show on the serial
	console?</para>
	</question>

	<answer>
	<para>See <ulink url="&url.books.handbook;/serialconsole-setup.html">this
	section of the handbook</ulink>.</para>
	</answer>
	</qandaentry>

	</qandaset>

	</sect1>

	<sect1 id="compatibility-sound">
	<title>Sound devices</title>

	<qandaset>

	<qandaentry>
	<question id="sound-card-support">
	<para>Which sound cards are supported by FreeBSD?</para>
	</question>

	<answer>
	<para>&os; supports various sound cards including the &soundblaster;,
	&soundblaster; Pro, &soundblaster; 16, Pro Audio Spectrum 16,
	AdLib, and Gravis UltraSound sound cards (for more details,
	see <ulink url="&url.base;/releases/">&os; Release Information</ulink>
	and the &man.snd.4; manual page).
	There is also limited support for
	MPU-401 and compatible MIDI cards. Cards conforming to the
	&microsoft; Sound System specification are also supported.</para>

	<note>
	<para>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.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="es1370-silent-pcm">
	<para>Workarounds for no sound from my &man.pcm.4; sound
	card?</para>
	</question>

	<answer>
	<para>Some sound cards, such as the es1370, set their output
	volume to 0 at every boot. Run the following command
	every time the machine boots:</para>

	<screen>&prompt.root; <userinput>mixer pcm 100 vol 100 cd 100</userinput></screen>
	</answer>
	</qandaentry>

	</qandaset>

	</sect1>

	<sect1 id="compatibility-other">
	<title>Other hardware</title>

	<qandaset>

	<qandaentry>
	<question id="power-management-support">
	<para>Does FreeBSD support power management on my
	laptop?</para>
	</question>

	<answer>
	<para>FreeBSD 4.X and later support <acronym>APM</acronym>
	on certain machines. Further information can be found in
	&man.apm.4;.</para>

	<para>FreeBSD 5.X and later support the
	<acronym>ACPI</acronym> features found in most modern
	hardware. Further information can be found in
	&man.acpi.4;. If a system supports both
	<acronym>APM</acronym> and <acronym>ACPI</acronym>, either
	can be used. We suggest you try both and choose the one
	that best fits your needs.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="disable-acpi">
	<para>How do I disable ACPI?</para>
	</question>

	<answer>
	<para>Add following line <screen>hint.acpi.0.disabled="1"</screen>
	into your <filename>/boot/device.hints</filename> file.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="micron-hang-boot">
	<para>Why does my Micron system hang at boot time?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>Disable the <quote>Plug and Play Operating System</quote>
	flag in the BIOS to work around this problem.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="asusk7v-boot-failure">
	<para>The boot floppy hangs on a system with an ASUS K7V
	motherboard. How do I fix this?</para>
	</question>

	<answer>
	<para>Go into the BIOS setup and disable the <quote>boot virus
	protection</quote>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="micron-3comnic-failure">
	<para>Why does my &tm.3com; PCI network card not work with my Micron
	computer?</para>
	</question>

	<answer>
	<para>See <link linkend="micron-hang-boot">the previous answer</link>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="newcard-does-not-work">
	<para>My PCMCIA card does not work. I have a message:
	<quote>cbb0: unsupported card type detected.</quote>
	What can I do?</para>
	</question>

	<answer>
	<para>You can try to use the original OLDCARD implementation. Edit
	your kernel configuration file and remove the following lines:
	<programlisting>device cbb
	device pccard
	device cardbus</programlisting>
	Then add:
	<programlisting>device pcic
	device card 1</programlisting>
	Rebuild and install the new kernel as described in
	<ulink url="&url.books.handbook;/kernelconfig.html">Configuring
	the FreeBSD Kernel</ulink>.</para>
	</answer>
	</qandaentry>
	</qandaset>

	</sect1>

	</chapter>

	<chapter id="troubleshoot">
	<title>Troubleshooting</title>

	<qandaset>
	<qandaentry>
	<question id="pae">
	<para>Why is &os; finding the wrong amount of memory?</para>
	</question>

	<answer>
	<para>The reason is the difference between physical memory addresses
	and virtual addresses.</para>

	<para>The convention for most PC hardware is to use the memory area
	between 3.5G and 4G for a special purpose (usually for PCI). This
	address space is used to access PCI hardware. As a result real,
	physical memory can not appear in that address space.</para>

	<para>What happens to the memory that should appear in that location
	is dependent on your hardware. Unfortunately, some hardware does
	nothing and the ability to use that last 500M of RAM is entirely
	lost.</para>

	<para>Luckily, most hardware remaps the memory to a higher location
	so that it can still be used. However, this can cause some
	confusion if you watch the boot messages.</para>

	<para>On a 32 bit version of &os;, the memory appears lost, since it
	will be remapped above 4G, which a 32 bit kernel is unable to
	access. In this case, the solution is to build a PAE enabled
	kernel. See <link linkend="memory-limits">this FAQ entry</link>
	for more information.</para>

	<para>On a 64 bit version of &os;, or when running a PAE-enabled
	kernel, &os; will correctly detect and remap the memory so it is
	usable. During boot, however, it may seem as if &os; is detecting
	more memory than the system really has. This is normal and the
	available memory will be corrected as the boot process
	completes.<para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="awre">
	<para>What do I do when I have bad blocks on my hard drive?</para>
	</question>

	<answer>
	<para>With SCSI drives, the drive should be capable of re-mapping
	these automatically. However, many drives ship with
	this feature disabled.</para>

	<para>To enable bad block remapping edit the first device page
	mode, which can be done by giving the command
	(as <username>root</username>)</para>

	<screen>&prompt.root; <userinput>camcontrol modepage sd0 -m 1 -e -P 3</userinput></screen>

	<para>and changing the values of AWRE and ARRE from 0 to 1:</para>

	<programlisting>AWRE (Auto Write Reallocation Enbld): 1
	ARRE (Auto Read Reallocation Enbld): 1</programlisting>

	<para>Modern IDE drives also have bad block remapping
	features in the controller, and they ship with this
	feature turned on.</para>

	<para>If you see warnings about bad blocks (on either type
	of drive), it is time to consider replacing the drive.
	You might be able to use the drive manufacturer's
	diagnostic program to lock out those bad blocks, but at
	best this will buy you some time.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="hpnetserver-scsi-failure">
	<para>Why does FreeBSD not detect my HP Netserver's SCSI
	controller?</para>
	</question>

	<answer>
	<para>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 <quote>true</quote> 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.</para>

	<para>So now, the best you can do is to pretend there is no
	address range clash :), by bumping the kernel option
	<literal>EISA_SLOTS</literal> to a value of 12. Configure and
	compile a kernel, as described in the <ulink
	url="&url.books.handbook;/kernelconfig.html">Handbook entry on
	configuring the kernel</ulink>.</para>

	<para>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
	<emphasis>UserConfig</emphasis>. Do not use the
	<quote>visual</quote> interface, but the plain command-line
	interface there. Simply type</para>

	<programlisting>eisa 12
	quit</programlisting>

	<para>at the prompt, and install your system as usual. While
	it is recommended you compile and install a custom kernel
	anyway.</para>

	<para>Hopefully, future versions will have a proper fix for
	this problem.</para>

	<note>
	<para>You cannot use a
	<literal>dangerously dedicated</literal> disk
	with an HP Netserver. See <link linkend="dedicate">this
	note</link> for more info.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ed1-timeout">
	<para>I keep seeing messages like
	<errorname>ed1: timeout</errorname>. What do these messages
	mean?</para>
	</question>

	<answer>
	<para>This is usually caused by an interrupt conflict (e.g.,
	two boards using the same IRQ). Boot with the
	-c option and change the ed0/de0/... entry to match your
	board.</para>

	<para>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.</para>

	<para>Some NE2000 compatible cards will give this error if there
	is no link on the UTP port or if the cable is disconnected.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="bad-3c509">
	<para>Why did my &tm.3com; 3C509 card stop working for no
	apparent reason?</para>
	</question>

	<answer>
	<para>This card has a bad habit of losing its configuration
	information. Refresh your card's settings with the DOS
	utility <command>3c5x9.exe</command>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="printer-slow">
	<para>My parallel printer is ridiculously slow. What can I do?</para>
	</question>

	<answer>
	<para>If the only problem is that the printer is terribly
	slow, try changing your <ulink
	url="&url.books.handbook;/printing-intro-setup.html#PRINTING-PARALLEL-PORT-MODE">printer
	port mode</ulink> as discussed in the <ulink
	url="&url.books.handbook;/printing-intro-setup.html">Printer
	Setup</ulink> section of the Handbook.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="signal11">
	<para>Why do my programs occasionally die with
	<errorname>Signal 11</errorname> errors?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>These problems can usually be attributed to either:</para>

	<orderedlist>
	<listitem>
	<para>If the problem is occurring only in a specific
	application that you are developing yourself it is probably
	a bug in your code.</para>
	</listitem>

	<listitem>
	<para>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).</para>
	</listitem>
	</orderedlist>

	<para>In particular, a dead giveaway that this is
	<emphasis>not</emphasis> 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.</para>

	<para>For example, suppose you are running <command>make
	<maketarget>buildworld</maketarget></command>, and the compile fails while trying to
	compile <filename>ls.c</filename> into
	<filename>ls.o</filename>. If you then run <command>make
	<maketarget>buildworld</maketarget></command> 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.</para>

	<para>What you should do:</para>

	<para>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.</para>

	<para>In the second case you need to verify that it is not your
	hardware at fault.</para>

	<para>Common causes of this include:</para>

	<orderedlist>
	<listitem>
	<para>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).</para>
	</listitem>

	<listitem>
	<para>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.</para>

	<para>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.</para>
	</listitem>

	<listitem>
	<para>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.</para>
	</listitem>

	<listitem>
	<para>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 <quote>RAM Speed: Turbo</quote> option, or
	similar in the BIOS will cause strange behavior. A
	possible idea is to set to BIOS defaults, but it might be
	worth noting down your settings first!</para>
	</listitem>

	<listitem>
	<para>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).</para>
	</listitem>

	</orderedlist>

	<para>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.</para>

	<para>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.</para>

	<para>There is an extensive FAQ on this at <ulink
	url="http://www.bitwizard.nl/sig11/">
	the SIG11 problem FAQ</ulink></para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="trap-12-panic">
	<para>My system crashes with either <errorname>Fatal
	trap 12: page fault in kernel mode</errorname>, or
	<errorname>panic:</errorname>, and spits out a
	bunch of information. What should I do?</para>
	</question>

	<answer>
	<para>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 <link linkend=
	"KERNEL-PANIC-TROUBLESHOOTING">kernel panics</link>,
	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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="screen-loses-sync">
	<para>Why does the screen go black and lose sync when I
	boot?</para>
	</question>

	<answer>
	<para>This is a known problem with the ATI Mach 64 video card.
	The problem is that this card uses address
	<literal>2e8</literal>, 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 <emphasis>even</emphasis> if
	you disable sio3 (the fourth port) which normally uses this
	address.</para>

	<para>Until the bug has been fixed, you can use this
	workaround:</para>

	<orderedlist>
	<listitem>
	<para>Enter <option>-c</option> at the boot prompt.
	(This will put the kernel into configuration mode).</para>
	</listitem>

	<listitem>
	<para>Disable <devicename>sio0</devicename>,
	<devicename>sio1</devicename>,
	<devicename>sio2</devicename> and
	<devicename>sio3</devicename> (all of them). This way
	the sio driver does not get activated -> no
	problems.</para>
	</listitem>

	<listitem>
	<para>Type exit to continue booting.</para>
	</listitem>
	</orderedlist>

	<para>If you want to be able to use your serial ports, you will
	have to build a new kernel with the following modification: in
	<filename>/usr/src/sys/i386/isa/sio.c</filename> find the one
	occurrence of the string <literal>0x2e8</literal> and remove
	that string and the preceding comma (keep the trailing comma).
	Now follow the normal procedure of building a new
	kernel.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="reallybigram">
	<para>Why does FreeBSD only use 64 MB of RAM when my system has
	128 MB of RAM installed?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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.</para>

	<para><literal>options "MAXMEM=<replaceable>n</replaceable>"</literal></para>

	<para>Where <replaceable>n</replaceable> is your memory in
	Kilobytes. For a 128 MB machine, you would want to use
	<literal>131072</literal>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="kmem-map-too-small">
	<para>My system has more than 1 GB of RAM, and I'm getting panics
	with <quote>kmem_map too small</quote> messages. What is wrong?
	</para>
	</question>

	<answer>
	<para>Normally, FreeBSD determines a number of kernel parameters,
	such as as the maximum number of files that can be open
	concurrently, from the amount of memory installed in the
	system. On systems with one gigabyte of RAM or more, this
	<quote>auto sizing</quote> mechanism may choose values that are
	too high: while starting up, the kernel allocates various tables
	and other structures that fill up most of the available kernel
	memory. Later on, while the system is running, the kernel has no
	more space left for dynamic memory allocations, and
	panics.</para>

	<para>Compile your own kernel, and add the
	<option>VM_KMEM_SIZE_MAX</option> to your kernel configuration
	file, increasing the maximum size to 400 MB
	(<option>options VM_KMEM_SIZE_MAX=419430400</option>).
	400 MB appears to be sufficient for machines with up to
	6 GB of memory.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="panic-kmemmap-too-small">
	<para>My system does not have 1 GB of RAM, and FreeBSD still
	panics with <errorname>kmem_map too small!</errorname>
	</para>
	</question>

	<answer>
	<para>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
	following the instructions in the <ulink
	url="&url.books.handbook;/configtuning-kernel-limits.html#NMBCLUSTERS">Network
	Limits</ulink> section of the Handbook.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="proc-table-full">
	<para>Why do I get the error <errorname>/kernel: proc: table
	is full</errorname>?</para>
	</question>

	<answer>
	<para>The FreeBSD kernel will only allow a certain number of
	processes to exist at one time. The number is based on
	the <literal>MAXUSERS</literal> option in the kernel
	configuration. <literal>MAXUSERS</literal> also affects
	various other in-kernel limits, such as network buffers
	(see <link linkend="panic-kmemmap-too-small">this</link>
	earlier question). If your machine is heavily loaded, you
	probably want to increase <literal>MAXUSERS</literal>.
	This will increase these other system limits in addition
	to the maximum number of processes.</para>

	<para>To adjust your <literal>MAXUSERS</literal> value, see
	the <ulink
	url="&url.books.handbook;/configtuning-kernel-limits.html#KERN-MAXFILES">File/Process
	Limits</ulink> section of the Handbook. (While that
	section refers to open files, the same limits apply to
	processes.)</para>

	<para>If your machine is lightly loaded, and you are simply
	running a very large number of processes, you can adjust
	this with the <varname>kern.maxproc</varname> tunable. If
	this tunable needs adjustion it needs to be defined in
	in <filename>/boot/loader.conf</filename>. The tunable
	will not get adjusted until the system is rebooted. For
	more information about tuning tunables, you should see the
	&man.loader.conf.5; and &man.sysctl.conf.5; manual pages.
	If these processes are being run by a single user, you will
	also need to adjust <varname>kern.maxprocperuid</varname>
	to be one less than your new
	<varname>kern.maxproc</varname> value. (It must be at
	least one less because one system program, &man.init.8;,
	must always be running.)</para>

	<para>To make a sysctl change permanent place the proper value
	in <filename>/etc/sysctl.conf</filename>. More information
	about system tuning with &man.sysctl.8; can be found at
	the <ulink
	url="&url.books.handbook;/configtuning-sysctl.html">Tuning
	with sysctl</ulink> section of the Handbook.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="cmap-busy-panic">
	<para>Why do I get an error reading <errorname>CMAP
	busy</errorname> when rebooting with a new
	kernel?</para>
	</question>

	<answer>
	<para>The logic that attempts to detect an out of date
	<filename>/var/db/kvm_*.db</filename> files sometimes fails
	and using a mismatched file can sometimes lead to panics.</para>

	<para>If this happens, reboot single-user and do:</para>

	<screen>&prompt.root; <userinput>rm /var/db/kvm_*.db</userinput></screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="brkadrint-illegal-host-access">
	<para>What does the message <errorname>ahc0: brkadrint,
	Illegal Host Access at seqaddr 0x0</errorname>
	mean?</para>
	</question>

	<answer>
	<para>This is a conflict with an Ultrastor SCSI Host Adapter.</para>

	<para>During the boot process enter the kernel configuration
	menu and disable
	<devicename>uha0</devicename>,
	which is causing the problem.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="aci0-illegal-cable">
	<para>When I boot my system, I get the error
	<errorname>ahc0: illegal cable configuration</errorname>.
	My cabling is correct. What is going on?</para>
	</question>

	<answer>
	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mail-loopback">
	<para>Why does Sendmail give me an error reading
	<quote><errorname>mail loops back to
	myself</errorname></quote>?</para>
	</question>

	<answer>
	<para>This is answered in the sendmail FAQ as follows:</para>

	<literallayout> * 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.
	</literallayout>

	<para>The current version of the <ulink
	url="ftp://rtfm.mit.edu/pub/usenet/news.answers/mail/sendmail-faq">sendmail
	FAQ</ulink> is no longer maintained with the sendmail release.
	It is however regularly posted to <ulink
	url="news:comp.mail.sendmail">comp.mail.sendmail</ulink>,
	<ulink url="news:comp.mail.misc">comp.mail.misc</ulink>, <ulink
	url="news:comp.mail.smail">comp.mail.smail</ulink>, <ulink
	url="news:comp.answers">comp.answers</ulink>, and <ulink
	url="news:news.answers">news.answers</ulink>. You can also
	receive a copy via email by sending a message to
	<email>mail-server@rtfm.mit.edu</email> with the command
	<literal>send usenet/news.answers/mail/sendmail-faq</literal>
	as the body of the message.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="remote-fullscreen">
	<para>Why do full screen applications on remote machines
	misbehave?</para>
	</question>

	<answer>
	<para>The remote machine may be setting your terminal type
	to something other than the <literal>cons25</literal> terminal
	type required by the FreeBSD console.</para>

	<para>There are a number of possible work-arounds for this
	problem:</para>
	<itemizedlist>
	<listitem>
	<para>After logging on to the remote machine, set your
	TERM shell variable to <literal>ansi</literal> or
	<literal>sco</literal> if the remote machine knows
	about these terminal types.</para>
	</listitem>

	<listitem>
	<para>Use a VT100 emulator like
	<application>screen</application> at the FreeBSD console.
	<application>screen</application> offers you the ability
	to run multiple concurrent sessions from one terminal,
	and is a neat program in its own right. Each
	<application>screen</application> window behaves like a
	VT100 terminal, so the TERM variable at the remote end
	should be set to <literal>vt100</literal>.</para>
	</listitem>

	<listitem>
	<para>Install the <literal>cons25</literal> 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.</para>
	</listitem>

	<listitem>
	<para>Fire up an X server at the FreeBSD end and login to
	the remote machine using an X based terminal emulator
	such as <command>xterm</command> or
	<command>rxvt</command>. The TERM variable at the remote
	host should be set to <literal>xterm</literal> or
	<literal>vt100</literal>.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="calcru-negative">
	<para>Why does my machine print
	<errorname>calcru: negative time...</errorname>?</para>
	</question>

	<answer>
	<para>This can be caused by various hardware 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.</para>

	<para>A side effect of this problem are dying processes with the
	message <quote>SIGXCPU exceeded cpu time limit</quote>.</para>

	<para>If the problem cannot be fixed otherwise the solution
	is to set this sysctl variable:</para>

	<screen>&prompt.root; <userinput>sysctl -w kern.timecounter.method=1</userinput></screen>

	<note>
	<para>The <option>-w</option> option of &man.sysctl.8; is
	deprecated and silently ignored in &os; 4.4-RELEASE and all
	newer versions. You can safely ommit it when setting options
	with <command>sysctl</command> as shown above.</para>
	</note>

	<para>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
	<literal>NTIMECOUNTER</literal> option in your kernel to
	increasingly large values. If by the time you have reached
	<literal>NTIMECOUNTER=20</literal> the problem is not solved,
	interrupts are too hosed on your machine for reliable
	time keeping.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="pnp-not-found">
	<para>Why is my PnP card no longer found (or found as
	<literal>unknown</literal>) since upgrading to FreeBSD 4.X?</para>
	</question>

	<answer>
	<para>FreeBSD 4.X is now much more <emphasis>PnP-centric</emphasis>
	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.</para>

	<para>The reasons for this behavior 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 <literal>[]</literal> have been added to clarify the
	context.</para>

	<note>
	<para>The contents of this quotation has been updated from
	its original text.</para>
	</note>

	<blockquote>
	<para>The PNP bios preconfigured it [the modem] and left it
	laying around in port space, so [in 3.X] the old-style ISA
	probes <quote>found</quote> it there.</para>

	<para>Under 4.0, the ISA code is much more PnP-centric. It was
	possible [in 3.X] for an ISA probe to find a
	<quote>stray</quote> 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
	ids for supported PnP hardware. Making this more user
	tweakable is on the TODO list.</para>
	</blockquote>

	<para>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:</para>

	<screen>&prompt.root; <userinput>pnpinfo</userinput>
	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)</screen>

	<para>[more TAG lines elided]</para>

	<screen>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</screen>

	<para>The information you require is in the
	<quote>Vendor ID</quote> 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.</para>

	<para>Alternatively, if &man.pnpinfo.8; does not list the card in
	question, &man.pciconf.8; can be used instead. This is part of
	the output from <command>pciconf -vl</command> for an onboard
	sound chip:</para>

	<screen>&prompt.root; <userinput>pciconf -vl</userinput>
	chip1@pci0:31:5: class=0x040100 card=0x00931028 chip=0x24158086 rev=0x02 hdr=0x00
	vendor = 'Intel Corporation'
	device = '82801AA 8xx Chipset AC'97 Audio Controller'
	class = multimedia
	subclass = audio</screen>

	<para>Here, you would use the <varname>chip</varname> value,
	<quote>0x24158086</quote>.</para>

	<para>This information (Vendor ID or chip value) needs adding
	to the file
	<filename>/usr/src/sys/isa/sio.c</filename>.</para>

	<para>You should first make a backup of <filename>sio.c</filename>
	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 <filename>sio.c</filename> and search
	for the line</para>

	<programlisting>static struct isa_pnp_id sio_ids[] = {</programlisting>

	<para>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 <emphasis>Device Description</emphasis>
	from the output of &man.pnpinfo.8;:</para>

	<programlisting>{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 */</programlisting>

	<para>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 <literal>sio</literal>
	device as it was under FreeBSD 3.X</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="nlist-failed">
	<para>Why do I get the error <errorname>nlist failed</errorname> when
	running, for example, <command>top</command> or
	<command>systat</command>?</para>
	</question>

	<answer>
	<para>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:</para>

	<itemizedlist>
	<listitem>
	<para>Your kernel and userland are not synchronized (i.e., you
	built a new kernel but did not do an
	<maketarget>installworld</maketarget>, 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
	<filename>/usr/src/UPDATING</filename> for the correct
	sequence).</para>
	</listitem>

	<listitem>
	<para>You are not using <command>/boot/loader</command> to load
	your kernel, but doing it directly from boot2 (see
	&man.boot.8;). While there is nothing wrong with bypassing
	<command>/boot/loader</command>, it generally does a better
	job of making the kernel symbols available to user
	applications.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="connection-delay">
	<para>Why does it take so long to connect to my computer via
	<command>ssh</command> or <command>telnet</command>?</para>
	</question>

	<answer>
	<para>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).</para>

	<para>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.</para>

	<para>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.</para>

	<para>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.</para>

	<para>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,
	<hostid>www.yahoo.com</hostid>. If it does not work, that is
	your problem.</para>

	<para>Following a fresh install of &os;, it is also possible
	that domain and nameserver information is missing from
	<filename>/etc/resolv.conf</filename>. This will often cause
	a delay in <application>SSH</application>, as the option
	<quote>UseDNS</quote> is set to <quote>yes</quote> by default
	in the <filename>sshd_config</filename> file in
	<filename>/etc/ssh</filename>. If this is causing the
	problem, you will either need to fill in the missing information
	in <filename>/etc/resolv.conf</filename> or set <quote>UseDNS</quote>
	to <quote>no</quote> in <filename>sshd_config</filename>
	as a temporary workaround.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="stray-irq">
	<para>What does <errorname>stray IRQ</errorname> mean?</para>
	</question>
	<answer>
	<para>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.</para>
	<para>One has three options for dealing with this:</para>
	<itemizedlist>
	<listitem>
	<para>Live with the warnings. All except the first 5
	per irq are suppressed anyway.</para>
	</listitem>
	<listitem>
	<para>Break the warnings by changing 5 to 0 in
	<function>isa_strayintr()</function> so that all the
	warnings are suppressed.</para>
	</listitem>
	<listitem>
	<para>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.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="file-table-full">
	<para>Why does <errorname>file: table is full</errorname> show up
	repeatedly in dmesg?</para>
	</question>
	<answer>
	<para>
	This error message indicates you have exhausted the number
	of available file descriptors on your system. Please see
	the <ulink
	url="&url.books.handbook;/configtuning-kernel-limits.html#KERN-MAXFILES">kern.maxfiles
	</ulink>section of the <ulink
	url="&url.books.handbook;/configtuning-kernel-limits.html">Tuning
	Kernel Limits</ulink> section of the Handbook for a
	discussion and solution.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="laptop-clock-skew">
	<para>Why does the clock on my laptop keep incorrect time?</para>
	</question>

	<answer>
	<para>Your laptop has two or more clocks, and FreeBSD has chosen to
	use the wrong one.</para>

	<para>Run &man.dmesg.8;, and check for lines that contain
	<literal>Timecounter</literal>. The last line printed is the one
	that FreeBSD chose, and will almost certainly be
	<literal>TSC</literal>.</para>

	<screen>&prompt.root; <userinput>dmesg \| grep Timecounter</userinput>
	Timecounter "i8254" frequency 1193182 Hz
	Timecounter "TSC" frequency 595573479 Hz</screen>

	<para>You can confirm this by checking the
	<varname>kern.timecounter.hardware</varname>
	&man.sysctl.3;.</para>

	<screen>&prompt.root; <userinput>sysctl kern.timecounter.hardware</userinput>
	kern.timecounter.hardware: TSC</screen>

	<para>The BIOS may modify the TSC clock—perhaps to change the
	speed of the processor when running from batteries, or going into
	a power saving mode, but FreeBSD is unaware of these adjustments,
	and appears to gain or lose time.</para>

	<para>In this example, the <literal>i8254</literal> clock is also
	available, and can be selected by writing its name to the
	<varname>kern.timecounter.hardware</varname>
	&man.sysctl.3;.</para>

	<screen>&prompt.root; <userinput>sysctl -w kern.timecounter.hardware=i8254</userinput>
	kern.timecounter.hardware: TSC -> i8254</screen>

	<para>Your laptop should now start keeping more accurate
	time.</para>

	<para>To have this change automatically run at boot time, add the
	following line to <filename>/etc/sysctl.conf</filename>.</para>

	<programlisting>kern.timecounter.hardware=i8254</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="null-null">
	<para>Why did my laptop fail to correctly probe PC cards?</para>
	</question>

	<answer>
	<para>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.
	<command>pccardd</command> will detect the card as
	<errorname>"(null)""(null)"</errorname> instead of its
	actual model.</para>

	<para>You must remove all power from the PC card slot to
	fully reset the hardware. Completely power off the
	laptop. (Do not suspend it, do not let it go into standby;
	the power needs to be completely off.) Wait a few
	moments, and reboot. Your PC card should work now.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="boot-read-error">
	<para>Why does FreeBSD's boot loader display
	<errorname>Read error</errorname> and stop after the BIOS
	screen?</para>
	</question>

	<answer>
	<para>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.
	</para>

	<para>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.
	</para>

	<para>Within &man.sysinstall.8;'s fdisk, hit
	<keycap>G</keycap> to set the drive geometry.</para>

	<para>A dialog will pop up requesting the number of
	cylinders, heads and sectors. Type the numbers found from
	the BIOS separated by forward slashes. For example, values
	of 5000 cylinders, 250 heads, and 60 sectors would be entered as
	<userinput>5000/250/60</userinput>.
	</para>

	<para>Press enter to set the values, and hit
	<keycap>W</keycap> to write the new partition table to the
	drive.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="bootmanager-restore">
	<para>Another operating system destroyed my Boot Manager. How do I
	get it back?</para>
	</question>

	<answer>
	<para>Enter &man.sysinstall.8; and choose Configure,
	then Fdisk. Select the disk the Boot Manager resided on
	with the <keycap>space</keycap> key. Press
	<keycap>W</keycap> to write changes to the drive. A prompt
	will appear asking which boot loader to install. Select this,
	and it will be restored.
	</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="indefinite-wait-buffer">
	<para>What does the error <errorname>swap_pager: indefinite
	wait buffer:</errorname> mean?</para>
	</question>

	<answer>
	<para>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
	<filename>/var/log/messages</filename> and in the output
	of <command>dmesg</command>. Otherwise, check your cables
	and connections.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="udma-icrc">
	<para>What are <quote>UDMA ICRC</quote> errors, and how do I
	fix them?</para>
	</question>

	<answer>
	<para>The &man.ata.4; driver reports <quote>UDMA ICRC</quote>
	errors when a DMA transfer to or from a drive is corrupted.
	The driver will retry the operation a few times. Should
	the retries fail, it will switch from DMA to the slower PIO
	mode of communication with the device.</para>

	<para>The problem can be caused by many factors, although
	perhaps the most common cause is faulty or incorrect
	cabling. Check that the ATA cables are undamaged and rated
	for the Ultra DMA mode in use. If you are using removable
	drive trays, they must also be compatible. Be sure that
	all connections are making good contact. Problems have
	also been noticed when an old drive is installed on the
	same ATA channel as an Ultra DMA 66 (or faster) drive.
	Lastly, these errors can indicate that the drive is
	failing. Most drive vendors provide testing software for
	their drives, so test your drive, and, if necessary, back
	up your data and replace it.</para>

	<para>The &man.atacontrol.8; utility can be used to show and
	select the DMA or PIO modes used for each ATA device. In
	particular, <command>atacontrol mode
	<replaceable>channel</replaceable></command> will show the
	modes in use on a particular ATA channel, where the primary
	channel is numbered 0, and so on.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="lock-order-reversal">
	<para>What is a <errorname>lock order reversal</errorname>?</para>
	</question>

	<answer>
	<para>&a.rwatson; answered this question very succinctly on
	the freebsd-current list in a thread entitled <quote><ulink
	url="http://docs.freebsd.org/cgi/getmsg.cgi?fetch=65165+0+/usr/local/www/db/text/2003/freebsd-current/20031221.freebsd-current">lock
	order reversals - what do they mean?</ulink></quote></para>

	<blockquote>
	<attribution>&a.rwatson; on freebsd-current, December 14,
	2003</attribution>

	<para>These warnings are generated by Witness, a run-time lock
	diagnostic system found in FreeBSD -CURRENT kernels (but
	removed in releases). You can read more about Witness in the
	&man.witness.4; man page, which talks about its capabilities. Among
	other things, Witness performs run-time lock order verification
	using a combination of hard coded lock orders, and run-time
	detected lock orders, and generates console warnings when lock
	orders are violated. The intent of this is to detect the
	potential for deadlocks due to lock order violations; it is worth
	observing that Witness is actually slightly conservative, and so
	it is possible to get false positives. In the event that Witness
	is accurately reporting a lock order problem, it is basically
	saying "If you were unlucky, a deadlock would have happened
	here". There are a couple of "well known" false positives,
	which we need to do a better job of documenting to prevent
	spurious reports. The non-well-known ones typically correspond
	to bugs in newly added locking, as lock order reversals usually
	get fixed pretty quickly because Witness is busy generating
	warnings :-).</para>
	</blockquote>

	<note>
	<para>A so-called "false positive" is actually Witness tripping
	over a much more serious bug. Such bugs are typically a page
	fault or memory corruption experienced inside of the kernel, or
	a name clash with mutexes.</para>
	</note>
	<note>
	<para>See <ulink
	url="http://sources.zabbadoz.net/freebsd/lor.html">Bjoern
	Zeeb's lock order reversal page</ulink> for the status of
	known lock order reversals.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="called-with-non-sleepable-locks-held">
	<para>What does <errorname>Called ... with the following
	non-sleepable locks held</errorname> mean?</para>
	</question>

	<answer>
	<para>This means that a function that may sleep was called while
	a mutex (or other unsleepable) lock was held.</para>

	<para>The reason this is an error is because mutexes are not
	intended to be held for long periods of time; they are
	supposed to only be held to maintain short periods of
	synchronization. This programming contract allows device
	drivers to use mutexes to synchronize with the rest of the kernel
	during interrupts. Interrupts (under FreeBSD) may not sleep.
	Hence it is imperative that no subsystem in the kernel
	block for an extended period while holding a mutex.</para>

	<para>To catch such errors, assertions may be added to the kernel
	that interact with the witness subsystem to emit a warning
	or fatal error (depending on the system configuration) when
	a potentially blocking call is made while holding a mutex.</para>

	<para>In summary, such warnings are non-fatal, however with
	unfortunate timing they could cause undesirable effects
	ranging from a minor blip in the system's responsiveness
	to a complete system lockup.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="touch-not-found">
	<para>Why does buildworld/installworld die with the message
	<errorname>touch: not found</errorname>?</para>
	</question>

	<answer>
	<para>This error does not mean that the &man.touch.1; utility is
	missing. The error is instead probably due to the dates of the
	files being set sometime in the future. If your CMOS-clock is
	set to local time you need to run the command
	<command>adjkerntz -i</command> to adjust the kernel clock
	when booting into single user mode.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="commercial">
	<title>Commercial Applications</title>

	<note>
	<para>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 <ulink
	url="&url.base;/commercial/index.html">the
	Vendors page</ulink> for a longer list.</para>
	</note>

	<qandaset>
	<qandaentry>
	<question id="officesuite">
	<para>Where can I get an Office Suite for FreeBSD?</para>
	</question>

	<answer>
	<para>The open-source <ulink
	url="http://www.openoffice.org">OpenOffice.org</ulink> office
	suite works natively on FreeBSD. The &linux; version of
	<ulink
	url="http://www.sun.com/staroffice/">StarOffice</ulink>,
	the value-added closed-source version of OpenOffice.org, also
	works on FreeBSD.</para>

	<para>FreeBSD also includes a variety of text editors,
	spreadsheets, and drawing programs in the Ports
	Collection.</para>
	</answer>
	</qandaentry>
	<qandaentry>
	<question id="motif">
	<para>Where can I get &motif; for FreeBSD?</para>
	</question>

	<answer>
	<para>The Open Group has released the source code to &motif; 2.2.2.
	You can install the <literal>open-motif</literal> package, or
	compile it from ports. Refer to
	<ulink url="&url.books.handbook;/ports.html">the ports section of the
	Handbook</ulink> for more information on how to do this.</para>

	<note>
	<para>The Open &motif; distribution only allows redistribution
	if it is running on an <ulink url="http://www.opensource.org/">
	open source</ulink> operating system.</para>
	</note>

	<para>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 <link linkend="apps2go">Apps2go</link> for the
	least expensive ELF &motif; 2.1.20 distribution for FreeBSD
	(&i386;).<anchor id="apps2go"></para>

	<para>There are two distributions, the <quote>development
	edition</quote> and the <quote>runtime edition</quote> (for
	much less). These distributions includes:</para>

	<itemizedlist>
	<listitem>
	<para>OSF/&motif; manager, xmbind, panner, wsm.</para>
	</listitem>

	<listitem>
	<para>Development kit with uil, mrm, xm, xmcxx, include
	and Imake files.</para>
	</listitem>

	<listitem>
	<para>Static and dynamic ELF libraries.</para>
	</listitem>

	<listitem>
	<para>Demonstration applets.</para>
	</listitem>
	</itemizedlist>

	<para>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
	<emphasis>Apps2go</emphasis>. This is currently a FTP only
	download.</para>

	<variablelist>
	<varlistentry>
	<term>More info</term>
	<listitem>
	<para><ulink url="http://www.apps2go.com/">
	Apps2go WWW page</ulink></para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>or</term>
	<listitem>
	<para>
	<email>sales@apps2go.com</email> or
	<email>support@apps2go.com</email>
	</para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>or</term>
	<listitem>
	<para>phone (817) 431 8775 or +1 817 431-8775</para>
	</listitem>
	</varlistentry>
	</variablelist>

	<para>Contact <link linkend="xig">Xi Graphics</link> for an
	a.out &motif; 2.0 distribution for FreeBSD.</para>

	<para>This distribution includes:</para>
	<itemizedlist>
	<listitem>
	<para>OSF/&motif; manager, xmbind, panner, wsm.</para>
	</listitem>

	<listitem>
	<para>Development kit with uil, mrm, xm, xmcxx, include
	and Imake files.</para>
	</listitem>

	<listitem>
	<para>Static and dynamic libraries (for use with FreeBSD
	2.2.8 and earlier).</para>
	</listitem>

	<listitem>
	<para>Demonstration applets.</para>
	</listitem>

	<listitem>
	<para>Preformatted manual pages.</para>
	</listitem>
	</itemizedlist>

	<para>Be sure to specify that you want the FreeBSD version
	of &motif; when ordering! Versions for BSDI and &linux; are also
	sold by <emphasis>Xi Graphics</emphasis>. This is currently a 4
	diskette set... in the future this will change to a unified CD
	distribution like their CDE.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="cde">
	<para>Where can I get CDE for FreeBSD?</para>
	</question>

	<answer>
	<para><link linkend="xig">Xi Graphics</link> used to sell CDE
	for FreeBSD, but no longer do.</para>

	<para><ulink url="http://www.kde.org/">KDE</ulink> is an open
	source X11 desktop which is similar to CDE in many respects.
	You might also like the look and feel of <ulink
	url="http://www.xfce.org/">xfce</ulink>. KDE and xfce are both
	in the <ulink url="&url.base;/ports/index.html">ports
	system</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="commercial-xserver">
	<para>Are there any commercial high-performance X servers?</para>
	</question>

	<answer>
	<para>Yes, <ulink url="http://www.xig.com/">Xi Graphics</ulink>
	sells Accelerated-X products for FreeBSD and other Intel based
	systems.</para>

	<para>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.<anchor id="xig"></para>

	<para>There is a free <quote>compatibility demo</quote> of
	version 5.0 available.</para>

	<para>Xi Graphics also sells &motif; and CDE for FreeBSD (see
	above).</para>

	<variablelist>
	<varlistentry>
	<term>More info</term>
	<listitem>
	<para><ulink url="http://www.xig.com/">
	Xi Graphics WWW page</ulink></para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>or</term>
	<listitem>
	<para><email>sales@xig.com</email>
	or <email>support@xig.com</email>
	</para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>or</term>
	<listitem>
	<para>phone (800) 946 7433 or +1 303 298-7478.</para>
	</listitem>
	</varlistentry>
	</variablelist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="database-systems">
	<para>Are there any Database systems for FreeBSD?</para>
	</question>

	<answer>
	<para>Yes! See the <ulink
	url="&url.base;/commercial/software_bycat.html#CATEGORY_DATABASE">
	Commercial Vendors</ulink> section of FreeBSD's Web site.</para>

	<para>Also see the <ulink
	url="&url.base;/ports/databases.html">
	Databases</ulink> section of the Ports collection.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="oracle-support">
	<para>Can I run &oracle; on FreeBSD?</para>
	</question>

	<answer>
	<para>Yes. The following pages tell you exactly how to set up
	&linux;-&oracle; on FreeBSD:</para>

	<itemizedlist>
	<listitem>
	<para><ulink
	url="http://www.unixcities.com/oracle/index.html">
	http://www.unixcities.com/oracle/index.html</ulink></para>
	</listitem>

	<listitem>
	<para><ulink
	url="http://www.shadowcom.net/freebsd-oracle9i/">
	http://www.shadowcom.net/freebsd-oracle9i/</ulink></para>

	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="applications">
	<title>User Applications</title>

	<qandaset>
	<qandaentry>
	<question id="user-apps">
	<para>So, where are all the user applications?</para>
	</question>

	<answer>
	<para>Please take a look at <ulink
	url="&url.base;/ports/index.html">the ports page</ulink>
	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
	<literal>freebsd-announce</literal> <link
	linkend="mailing">mailing list</link> for periodic updates
	on new entries.</para>

	<para>Most ports should work on the 4.X, 5.X, and 6.X branches.
	Each time a FreeBSD release is made, a snapshot of the
	ports tree at the time of release in also included in the
	<filename>ports/</filename> directory.</para>

	<para>We also support the concept of a
	<quote>package</quote>, essentially no more than a compressed
	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.</para>

	<para>Use the package installation menu in
	<filename>/stand/sysinstall</filename> (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 <filename>.tgz</filename> or <filename>.tbz</filename> suffix and
	CDROM distribution people will have a
	<filename>packages/All</filename> 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:</para>

	<variablelist>
	<varlistentry>
	<term>for 4.X-RELEASE/4-STABLE</term>
	<listitem>
	<para><ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/">
	ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/</ulink></para>

	</listitem>
	</varlistentry>

	<varlistentry>
	<term>for 5.X-RELEASE/5-STABLE</term>
	<listitem>
	<para><ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-stable/">
	ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-stable</ulink></para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>for 6.X-RELEASE/6-STABLE</term>
	<listitem>
	<para><ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-6-stable/">
	ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-6-stable</ulink></para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>for 7-CURRENT</term>
	<listitem>
	<para><ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-7-current/">
	ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-7-current</ulink></para>
	</listitem>
	</varlistentry>
	</variablelist>

	<para>or your nearest local mirror site.</para>

	<para>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 <ulink
	url="ftp://ftp.FreeBSD.org/pub/FreeBSD/">ftp.FreeBSD.org</ulink>
	master site.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="configure-inn">
	<para>How do I configure INN (Internet News) for my machine?</para>
	</question>

	<answer>
	<para>After installing the <filename
	role="package">news/inn</filename> package or port, an
	excellent place to start is <ulink
	url="http://www.visi.com/~barr/INN.html">Dave
	Barr's INN Page</ulink> where you will find the INN
	FAQ.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="java">
	<para>Does FreeBSD support &java;?</para>
	</question>

	<answer>
	<para>Yes. Please see <ulink
	url="&url.base;/java/index.html">
	http://www.FreeBSD.org/java/</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ports-4x">
	<para>Why can I not build this port on my 4.X-STABLE machine?</para>
	</question>

	<answer>
	<para>If you are running a FreeBSD version that lags
	significantly behind -CURRENT or -STABLE, you may need to
	update your ports collection; see the <ulink
	url="&url.books.porters-handbook;/keeping-up.html">
	Keeping Up</ulink> section of the Porter's Handbook for further
	information on how to do this.
	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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="make-index">
	<para>I just tried to build <filename>INDEX</filename>
	using <command>make index</command>, and it failed.
	Why?</para>
	</question>

	<answer>
	<para>First, always make sure that you have a completely
	up-to-date Ports Collection. Errors that affect building
	<filename>INDEX</filename> from an up-to-date copy of the
	Ports Collection are high-visibility and are thus almost
	always fixed immediately.</para>

	<para>However, if you are up-to-date, perhaps you are seeing
	another problem. <command>make index</command> has a
	known bug in dealing with incomplete copies of the Ports
	Collection. It assumes that you have a local copy of every
	single port that every other port that you have a local copy
	of depends on. To explain, if you have a copy of
	<filename>foo/bar</filename> on your disk, and
	<filename>foo/bar</filename> depends on
	<filename>baz/quux</filename>, then you must also have
	a copy of <filename>baz/quux</filename> on your disk, and
	the ports <filename>baz/quux</filename> depends on, and
	so on. Otherwise, <command>make index</command> has
	insufficient information to create its dependency tree.</para>

	<para>This is particularly a problem for &os; users who
	utilize &man.cvsup.1; to track the Ports Collection but
	choose not to install certain categories by specifying
	them in <filename>refuse</filename>. In theory, one
	should be able to refuse categories, but in practice
	there are too many ports that depend on ports in other
	categories. Until someone comes up with a solution for
	this problem, the general rule is is that if you want to
	build <filename>INDEX</filename>, you must have a complete
	copy of the Ports Collection.</para>

	<para>There are rare cases where <filename>INDEX</filename>
	will not build due to odd cases involving
	<makevar>WITH_<replaceable>*</replaceable></makevar> or
	<makevar>WITHOUT_<replaceable>*</replaceable></makevar>
	variables being set in <filename>make.conf</filename>. If
	you suspect that this is the case, please try to make
	<filename>INDEX</filename> with those Makevars turned off
	before reporting it to &a.ports;.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="cvsup-in-base">
	<para>Why is CVSup not integrated in the main FreeBSD tree?
	</para>
	</question>

	<answer>
	<para>The FreeBSD base system is designed as self-hosting - it
	should be possible to build the whole operating system starting
	with a very limited set of tools. Thus, the actual build tools
	needed to compile the FreeBSD sources are bundled with the
	sources themselves. This includes a C compiler (&man.gcc.1;),
	&man.make.1;, &man.awk.1;, and similar tools.</para>

	<para>Since CVSup is written in Modula-3, adding it to the FreeBSD
	base system would also require adding and maintaining a Modula-3
	compiler. This would lead to both an increase in the disk space
	consumed by the FreeBSD sources and additional maintenance work.
	Thus, it is much easier for both the developers and users to
	keep CVSup as a separate port, which can be easily installed as
	a package bundled on the FreeBSD installation CDs.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ports-update">
	<para>I updated the sources, now how do I update my installed
	ports?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>The &man.pkg.version.1; command can generate a script
	that will update installed ports to the latest version in
	the ports tree.</para>

	<screen>&prompt.root; <userinput>pkg_version -c > <replaceable>/tmp/myscript</replaceable></userinput></screen>

	<para>The output script <emphasis>must</emphasis> be edited by
	hand before you use it. Recent versions of
	&man.pkg.version.1; force this by inserting an
	&man.exit.1; at the beginning of the script.</para>

	<para>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.</para>

	<note>
	<para>Beginning with FreeBSD 5.0 (and higher revisions),
	&man.pkg.version.1; no longer supports the
	<option>-c</option> option.</para>
	</note>

	<para>If you have the disk space, you can use the
	<command>portupgrade</command> tool to automate all of
	this. <command>portupgrade</command> includes various
	tools to simplify package handling. It is available under
	<filename role="package">ports-mgmt/portupgrade</filename>.
	Since it is written in Ruby,
	<command>portupgrade</command> is an unlikely candidate for
	integration with the main FreeBSD tree. That should not
	stop anyone from using it, however.</para>

	<para>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
	<literal>weekly_status_pkg_enable="YES"</literal> in
	<filename>/etc/periodic.conf</filename>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="minimal-sh">
	<para>Why is <command>/bin/sh</command> so minimal? Why does
	FreeBSD not use <command>bash</command> or another shell?</para>
	</question>

	<answer>
	<para>Because &posix; says that there shall be such a shell.</para>

	<para>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.</para>

	<para>The existing implementation is our best effort at meeting as
	many of these requirements simultaneously as we can. In order to
	keep <command>/bin/sh</command> 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
	<quote>VSZ</quote> and <quote>RSS</quote> columns in a <command>ps
	-u</command> listing.)</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="netscape-slow-startup">
	<para>Why do &netscape; and Opera take so long to
	start?</para>
	</question>

	<answer>
	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ports-base-update">
	<para>I updated parts of the Ports Collection using CVSup, and
	now many ports fail to build with mysterious error messages!
	What happened? Is the Ports Collection broken in some major
	way?</para>
	</question>

	<answer>
	<para>If you only update parts of the Ports Collection, using
	one of its CVSup subcollections and not the
	<literal>ports-all</literal> CVSup collection, you should
	<emphasis>always</emphasis> update the
	<literal>ports-base</literal> subcollection too! The reasons
	are described <ulink
	url="&url.books.handbook;/cvsup.html#CVSUP-COLLEC-PBASE-WARN">in the
	Handbook</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="midi-sound-files">
	<para>How do I create audio CDs from my MIDI files?</para>
	</question>

	<answer><para>To create audio CDs from MIDI files, first
	install <filename role="package">audio/timidity++</filename>
	from ports then install manually the GUS patches set by Eric
	A. Welsh, available at <ulink
	url="http://alleg.sourceforge.net/digmid.html"></ulink>.
	After timidity++ has been installed properly, midi files may
	be converted to wav files with the following command
	line:</para>

	<screen>&prompt.user; <userinput>timidity -Ow -s 44100 -o /tmp/juke/01.wav 01.mid</userinput></screen>

	<para>The wav files can then be converted to other formats
	or burned onto audio CDs, as described in the FreeBSD
	Handbook.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="kernelconfig">
	<title>Kernel Configuration</title>

	<qandaset>
	<qandaentry>
	<question id="make-kernel">
	<para>I would like to customize my kernel. Is it difficult?</para>
	</question>

	<answer>
	<para>Not at all! Check out the <ulink
	url="&url.books.handbook;/kernelconfig.html">
	kernel config section of the Handbook</ulink>.</para>

	<note>
	<para>We recommend that you make a dated snapshot of
	your new <filename>/kernel</filename> called
	<filename>/kernel.YYMMDD</filename> after you get it
	working properly. Also back up your new
	<filename>/modules</filename> directory to
	<filename>/modules.YYMMDD</filename>. 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
	<filename>kernel.GENERIC</filename>. This is
	particularly important if you are now booting from a
	controller that GENERIC does not support.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="missing-hw-float">
	<para>My kernel compiles fail because
	<literal>_hw_float</literal> is missing. How do I solve
	this problem?</para>
	</question>

	<answer>
	<para>You probably removed <devicename>npx0</devicename>
	(see &man.npx.4;) from your kernel configuration file
	because you do not have a math co-processor. The
	<devicename>npx0</devicename> device is
	<emphasis>MANDATORY</emphasis>. Somewhere inside your
	hardware lies a device that provides hardware
	floating-point support, even if it is no longer a separate
	device as used in the good old 386 days. You
	<emphasis>must</emphasis> include the
	<devicename>npx0</devicename> device. Even if you manage
	to build a kernel without <devicename>npx0</devicename>
	support, it will not boot anyway. </para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="why-kernel-big">
	<para>Why is my kernel so big (over 10MB)?</para>
	</question>

	<answer>
	<para>Chances are, you compiled your kernel in
	<emphasis>debug mode</emphasis>. Kernels built in debug
	mode contain many symbols that are used for debugging,
	thus greatly increasing the size of the kernel. Note that
	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.</para>

	<para>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:</para>

	<itemizedlist>
	<listitem>
	<para>You do not have a line in your kernel
	configuration file that reads:</para>

	<programlisting>makeoptions DEBUG=-g</programlisting>
	</listitem>

	<listitem>
	<para>You are not running &man.config.8; with
	the <option>-g</option> option.</para>
	</listitem>
	</itemizedlist>

	<para>Either of the above settings 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="multiport-serial-interrupts">
	<para>Why do I get interrupt conflicts with multi-port serial
	code?</para>
	</question>

	<answer>
	<para>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?</para>

	<para>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 an example:</para>

	<programlisting>#
	# 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</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="generic-kernel-build-failure">
	<para>Why does every kernel I try to build fail to compile, even
	GENERIC?</para>
	</question>

	<answer>
	<para>There are a number of possible causes for this problem.
	They are, in no particular order:</para>

	<itemizedlist>
	<listitem>
	<para>You are not using the new <command>make
	buildkernel</command> and <command>make
	installkernel</command> 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
	<filename>/usr/src/UPDATING</filename> file, paying
	particular attention to the <quote>COMMON ITEMS</quote>
	section at the end.</para>
	</listitem>

	<listitem>
	<para>You are using the new <command>make
	buildkernel</command> and <command>make
	installkernel</command> targets, but you failed to assert
	the completion of the <command>make buildworld</command>
	target. The <command>make buildkernel</command> target
	relies on files generated by the <command>make
	buildworld</command> target to complete its job
	correctly.</para>
	</listitem>

	<listitem>
	<para>Even if you are trying to build <link
	linkend="stable">FreeBSD-STABLE</link>, 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 <link
	linkend="stable">FreeBSD-STABLE</link> 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.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="scheduler-in-use">
	<para>How can I verify which scheduler is in use on a
	running system?</para>
	</question>

	<answer>
	<para>If you are running &os; version 5.2.1 or earlier, check for
	the existence of the <literal>kern.quantum</literal> sysctl.
	If you have it, you should see something like this:</para>

	<screen>&prompt.user; sysctl <replaceable>kern.quantum</replaceable>
	kern.sched.quantum: 99960</screen>

	<para>If the <literal>kern.quantum</literal> sysctl exists, you are
	using the 4BSD scheduler. If not, you will get an error printed
	by &man.sysctl.8; (which you can safely ignore):</para>

	<screen>&prompt.user; sysctl <replaceable>kern.sched.quantum</replaceable>
	sysctl: unknown oid 'kern.sched.quantum'</screen>

	<para>In &os; version 5.3-RELEASE and later, the name of the
	scheduler currently being used is directly available as the value
	of the <literal>kern.sched.name</literal> sysctl:</para>

	<screen>&prompt.user; sysctl <replaceable>kern.sched.name</replaceable>
	kern.sched.name: 4BSD</screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="scheduler-kern-quantum">
	<para>What is <literal>kern.quantum</literal>?</para>
	</question>

	<answer>
	<para><literal>kern.quantum</literal> is the maximum number of
	ticks a process can run without being preempted. It is
	specific to the 4BSD scheduler, so you can use its
	presence or absence to determine which scheduler is in
	use. In &os; 5.X or later <literal>kern.quantum</literal> has
	been renamed to <literal>kern.sched.quantum</literal>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="scheduler-kern-sched-quantum">
	<para>What is <literal>kern.sched.quantum</literal>?</para>
	</question>

	<answer>
	<para>See <xref linkend="scheduler-kern-quantum"></para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="disks">
	<title>Disks, Filesystems, and Boot Loaders</title>

	<qandaset>
	<qandaentry>
	<question id="adding-disks">
	<para>How can I add my new hard disk to my FreeBSD system?</para>
	</question>

	<answer>
	<para>See the Disk Formatting Tutorial at <ulink
	url="&url.articles.formatting-media;/index.html">
	www.FreeBSD.org</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="new-huge-disk">
	<para>How do I move my system over to my huge new disk?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>Should you decide not to do a fresh install, you
	need to partition and label the new disk with either
	<filename>/stand/sysinstall</filename>, 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 <ulink
	url="&url.articles.formatting-media;/index.html">
	formatting-media article</ulink> for details on this
	process.</para>

	<para>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
	<filename>/dev</filename>), 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.</para>

	<para>You should never use anything but &man.dump.8; and
	&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:</para>

	<procedure>
	<step>
	<para>newfs the new partition.</para>
	</step>

	<step>
	<para>mount it on a temporary mount point.</para>
	</step>

	<step>
	<para>cd to that directory.</para>
	</step>

	<step>
	<para>dump the old partition, piping output to the
	new one.</para>
	</step>
	</procedure>

	<para>For example, if you are going to move root to
	<devicename>/dev/ad1s1a</devicename>, with
	<filename>/mnt</filename> as the temporary mount point,
	it is:</para>

	<screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
	&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
	&prompt.root; <userinput>cd /mnt</userinput>
	&prompt.root; <userinput>dump 0af - / \| restore xf -</userinput></screen>

	<para>Rearranging your partitions with dump takes a bit more
	work. To merge a partition like <filename>/var</filename>
	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:</para>

	<screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
	&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
	&prompt.root; <userinput>cd /mnt</userinput>
	&prompt.root; <userinput>dump 0af - / \| restore xf -</userinput>
	&prompt.root; <userinput>cd var</userinput>
	&prompt.root; <userinput>dump 0af - /var \| restore xf -</userinput></screen>

	<para>To split a directory from its parent, say putting
	<filename>/var</filename> 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:</para>

	<screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
	&prompt.root; <userinput>newfs /dev/ad1s1d</userinput>
	&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
	&prompt.root; <userinput>mkdir /mnt/var</userinput>
	&prompt.root; <userinput>mount /dev/ad1s1d /mnt/var</userinput>
	&prompt.root; <userinput>cd /mnt</userinput>
	&prompt.root; <userinput>dump 0af - / \| restore xf -</userinput></screen>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="dangerously-dedicated">
	<para>Will a <quote>dangerously dedicated</quote> disk endanger
	my health?</para>
	</question>

	<answer>

	<para><anchor id="dedicate">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 <quote>slices</quote> 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.</para>

	<para>So why it is called <quote>dangerous</quote>? 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
	<quote>dangerously dedicated</quote> 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 <errorname>read error</errorname> message printed by
	the FreeBSD bootstrap when it cannot find itself, as well
	as system lockups when booting.</para>

	<para>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. <quote>Dangerously dedicated</quote> mode's
	origins lie in a desire to avoid one of the most common
	problems plaguing new FreeBSD installers - matching the BIOS
	<quote>geometry</quote> numbers for a disk to the disk
	itself.</para>

	<para><quote>Geometry</quote> 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.</para>

	<para><quote>Dangerously dedicated</quote> 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.</para>

	<para>So, how do you avoid the need for <quote>DD</quote> 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
	<option>-v</option> at the <literal>boot:</literal> prompt, or
	using <command>boot -v</command> 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.</para>

	<para>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
	<keycap>g</keycap> 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.</para>

	<para>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 <quote>DD</quote> mode at all. If,
	however, you are still greeted with the dreaded <errorname>read
	error</errorname> message when you try to boot, it is time to cross
	your fingers and go for it - there is nothing left to
	lose.</para>

	<para>To return a <quote>dangerously dedicated</quote> 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</para>

	<screen>&prompt.root; <userinput>dd if=/dev/zero of=/dev/rda0 count=15</userinput></screen>

	<para>Alternatively, the undocumented DOS
	<quote>feature</quote></para>

	<screen><prompt>C:\></prompt> <userinput>fdisk /mbr</userinput></screen>

	<para>will to install a new master boot record as well, thus
	clobbering the BSD bootstrap.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="safe-softupdates">
	<para>Which partitions can safely use Soft Updates? I have
	heard that Soft Updates on <filename>/</filename> can cause
	problems.</para>
	</question>

	<answer>
	<para>Short answer: you can usually use Soft Updates safely
	on all partitions.</para>

	<para>Long answer: There used to be some concern over using
	Soft Updates on the root partition. Soft Updates has two
	characteristics that caused this. First, a Soft Updates
	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, Soft Updates can cause
	temporary space shortages.</para>

	<para>When using Soft Updates, 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.</para>

	<para>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 Soft Updates.</para>

	<para>These issues affect all partitions using Soft Updates.
	So, what does this mean for the root partition?</para>

	<para>Vital information on the root partition changes very
	rarely. Files such as <filename>/kernel</filename> and
	the contents of <filename>/etc</filename> 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 Soft Updates on the root filesystem!</para>

	<para><filename>/</filename> is traditionally one of the
	smallest partitions. By default, FreeBSD puts the
	<filename>/tmp</filename> directory on
	<filename>/</filename>. If you have a busy
	<filename>/tmp</filename>, you might see intermittent
	space problems. Symlinking <filename>/tmp</filename> to
	<filename>/var/tmp</filename> will solve this
	problem.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="inappropriate-ccd">
	<para>What is inappropriate about my ccd?</para>
	</question>

	<answer>
	<para>The symptom of this is:</para>

	<screen>&prompt.root; <userinput>ccdconfig -C</userinput>
	ccdconfig: ioctl (CCDIOCSET): /dev/ccd0c: Inappropriate file type or format</screen>

	<para>This usually happens when you are trying to concatenate
	the <literal>c</literal> partitions, which default to type
	<literal>unused</literal>. 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 <literal>4.2BSD</literal>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ccd-disklabel">
	<para>Why can I not edit the disklabel on my ccd?</para>
	</question>

	<answer>
	<para>The symptom of this is:</para>

	<screen>&prompt.root; <userinput>disklabel ccd0</userinput>
	(it prints something sensible here, so let us try to edit it)
	&prompt.root; <userinput>disklabel -e ccd0</userinput>
	(edit, save, quit)
	disklabel: ioctl DIOCWDINFO: No disk label on disk;
	use "disklabel -r" to install initial label</screen>

	<para>This is because the disklabel returned by ccd is actually
	a <quote>fake</quote> one that is not really on the disk.
	You can solve this problem by writing it back explicitly,
	as in:</para>

	<screen>&prompt.root; <userinput>disklabel ccd0 > /tmp/disklabel.tmp</userinput>
	&prompt.root; <userinput>disklabel -Rr ccd0 /tmp/disklabel.tmp</userinput>
	&prompt.root; <userinput>disklabel -e ccd0</userinput>
	(this will work now)</screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mount-foreign-fs">
	<para>Can I mount other foreign filesystems under FreeBSD?</para>
	</question>

	<answer>
	<para>FreeBSD supports a variety of other
	filesystems.</para>

	<variablelist>
	<varlistentry>
	<term>Digital UNIX</term>

	<listitem>
	<para>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.</para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>&linux;</term>

	<listitem>
	<para>FreeBSD supports <literal>ext2fs</literal>
	partitions. See &man.mount.ext2fs.8; for more
	information.</para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>&windowsnt;</term>

	<listitem>
	<para>FreeBSD includes a read-only NTFS driver. For
	more information, see &man.mount.ntfs.8;.
	</para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>FAT</term>

	<listitem>
	<para>FreeBSD includes a read-write FAT driver. For
	more information, see &man.mount.msdosfs.8;.</para>
	</listitem>
	</varlistentry>

	<varlistentry>
	<term>ReiserFS</term>

	<listitem>
	<para>FreeBSD includes a read-only ReiserFS driver. For
	more information, see &man.mount.reiserfs.8;.</para>
	</listitem>
	</varlistentry>
	</variablelist>

	<para>FreeBSD also supports network filesystems such as NFS
	(see &man.mount.nfs.8;), NetWare (see &man.mount.nwfs.8;),
	and Microsoft-style SMB filesystems (see
	&man.mount.smbfs.8;).
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mount-dos">
	<para>How do I mount a secondary DOS partition?</para>
	</question>

	<answer>

	<para>The secondary DOS partitions are found after ALL the
	primary partitions. For example, if you have an
	<quote>E</quote> partition as the second DOS partition on
	the second SCSI drive, you need to create the special files
	for <quote>slice 5</quote> in <filename>/dev</filename>,
	then mount <devicename>/dev/da1s5</devicename>:</para>

	<screen>&prompt.root; <userinput>cd /dev</userinput>
	&prompt.root; <userinput>sh MAKEDEV da1s5</userinput>
	&prompt.root; <userinput>mount -t msdos /dev/da1s5 /dos/e</userinput></screen>

	<note>
	<para>You can omit this step if you are running FreeBSD
	5.0-RELEASE or newer with &man.devfs.5;
	enabled.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="crypto-filesystem">
	<para>Is there a cryptographic filesystem for &os;?</para>
	</question>

	<answer>

	<para>Yes. FreeBSD 5.0 includes &man.gbde.8;, and FreeBSD 6.0
	added &man.geli.8;. For earlier releases, see the <filename
	role="package">security/cfs</filename> port.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="nt-bootloader">
	<para>How can I use the &windowsnt; loader to boot FreeBSD?</para>
	</question>

	<answer>
	<para>The general idea is that you copy the first sector of your
	native root FreeBSD partition into a file in the DOS/&windowsnt;
	partition. Assuming you name that file something like
	<filename>c:\bootsect.bsd</filename> (inspired by
	<filename>c:\bootsect.dos</filename>), you can then edit the
	<filename>c:\boot.ini</filename> file to come up with something
	like this:</para>

	<programlisting>[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"</programlisting>

	<para>If FreeBSD is installed on the same disk as the &windowsnt; boot
	partition simply copy <filename>/boot/boot1</filename> to
	<filename>C:\BOOTSECT.BSD</filename>. However, if FreeBSD is
	installed on a different disk <filename>/boot/boot1</filename>
	will not work, <filename>/boot/boot0</filename> is needed.</para>

	<para><filename>/boot/boot0</filename> 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 <filename>/boot/boot0</filename>
	has the partition table area filled with NULL characters
	but sysinstall copies the partition table before copying
	<filename>/boot/boot0</filename> to the MBR.</para>

	<warning>
	<para><emphasis>Do not simply copy <filename>/boot/boot0</filename>
	instead of <filename>/boot/boot1</filename>; you will
	overwrite your partition table and render your computer
	un-bootable!</emphasis></para>
	</warning>

	<para>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
	<filename>/boot/boot0</filename> to
	<filename>C:\BOOTSECT.BSD</filename> then it writes an empty
	partition table, with the active flag set on one entry, to the
	MBR.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="lilo-bootloader">
	<para>How do I boot FreeBSD and &linux; from LILO?</para>
	</question>

	<answer>
	<para>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:</para>

	<para>Boot &linux;, and add the following lines to
	<filename>/etc/lilo.conf</filename>:</para>

	<programlisting>other=/dev/hda2
	table=/dev/hda
	label=FreeBSD</programlisting>

	<para>(the above assumes that your FreeBSD slice is known to
	&linux; as <devicename>/dev/hda2</devicename>; tailor to
	suit your setup). Then, run <command>lilo</command> as
	<username>root</username> and you should be done.</para>

	<para>If FreeBSD resides on another disk, you need to add
	<literal>loader=/boot/chain.b</literal> to the LILO entry.
	For example:</para>

	<programlisting>other=/dev/dab4
	table=/dev/dab
	loader=/boot/chain.b
	label=FreeBSD</programlisting>

	<para>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:</para>

	<screen>Boot: <userinput>1:da(0,a)/kernel</userinput></screen>

	<para>You can configure
	&man.boot.8;
	to automatically do this for you at boot time.</para>

	<para>The <ulink
	url="http://sunsite.unc.edu/LDP/HOWTO/mini/Linux+FreeBSD.html">
	&linux;+FreeBSD mini-HOWTO</ulink> is a good reference for
	FreeBSD and &linux; interoperability issues.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="grub-loader">
	<para>How do I boot &os; and &linux; using GRUB</para>
	</question>

	<answer>
	<para>Booting &os; using GRUB is very simple. Just
	add the following to your configuration file
	<filename>/boot/grub/grub.conf</filename>.</para>

	<programlisting>title FreeBSD 6.1
	root (hd0,a)
	kernel /boot/loader
	</programlisting>

	<para>Where <literal>hd0,a</literal> points to your root partition
	on the first disk. If you need to specify which slice number
	should be used, use something like this <literal>(hd0,2,a)</literal>.
	By default, if the slice number is omitted, GRUB searches the
	first slice which has <literal>'a'</literal> partition.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="booteasy-loader">
	<para>How do I boot FreeBSD and &linux; using BootEasy?</para>
	</question>

	<answer>
	<para>Install LILO at the start of your &linux; boot partition
	instead of in the Master Boot Record. You can then boot LILO
	from BootEasy.</para>

	<para>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 &windows; 95 (which is a Jealous
	Operating System, and will bear no other Operating Systems in
	the Master Boot Record).</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="changing-bootprompt">
	<para>How do I change the boot prompt from <literal>???</literal> to
	something more meaningful?</para>
	</question>

	<answer>
	<para>You can not do that with the standard boot manager without
	rewriting it. There are a number of other boot managers
	in the <filename>sysutils</filename> ports category that
	provide this functionality.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="removable-drives">
	<para>I have a new removable drive, how do I use it?</para>
	</question>

	<answer>

	<para>Whether it is a removable drive like a &iomegazip; 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.</para>

	<para>(this section is based on <ulink
	url="http://www.vmunix.com/mark/FreeBSD/ZIP-FAQ.html">
	Mark Mayo's ZIP FAQ</ulink>)</para>

	<para>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:</para>

	<screen>&prompt.root; <userinput>mount -t msdos /dev/fd0c /floppy</userinput></screen>

	<para>if it is a floppy, or this:</para>

	<screen>&prompt.root; <userinput>mount -t msdos /dev/da2s4 /zip</userinput></screen>

	<para>for a ZIP disk with the factory configuration.</para>

	<para>For other disks, see how they are laid out using
	&man.fdisk.8; or
	&man.sysinstall.8;.</para>

	<para>The rest of the examples will be for a ZIP drive on da2,
	the third SCSI disk.</para>

	<para>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
	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
	<filename>/stand/sysinstall</filename>, 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:</para>

	<screen>&prompt.root; <userinput>dd if=/dev/zero of=/dev/rda2 count=2</userinput>
	&prompt.root; <userinput>disklabel -Brw da2 auto</userinput></screen>

	<para>You can use disklabel or
	<filename>/stand/sysinstall</filename> 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.</para>

	<para>Finally, create a new filesystem, this one is on our ZIP
	drive using the whole disk:</para>

	<screen>&prompt.root; <userinput>newfs /dev/rda2c</userinput></screen>

	<para>and mount it:</para>

	<screen>&prompt.root; <userinput>mount /dev/da2c /zip</userinput></screen>

	<para>and it is probably a good idea to add a line like this
	to <filename>/etc/fstab</filename> (see &man.fstab.5;) so
	you can just type <command>mount /zip</command> in the
	future:</para>

	<programlisting>/dev/da2c /zip ffs rw,noauto 0 0</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mount-cd-superblock">
	<para>Why do I get <errorname>Incorrect super block</errorname> when
	mounting a CDROM?</para>
	</question>

	<answer>
	<para>You have to tell &man.mount.8; the type of the device
	that you want to mount. This is described in the <ulink
	url="&url.books.handbook;/creating-cds.html"> Handbook section on
	optical media</ulink>, specifically the section <ulink
	url="&url.books.handbook;/creating-cds.html#MOUNTING-CD">Using Data
	CDs</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="cdrom-not-configured">
	<para>Why do I get <errorname>Device not
	configured</errorname> when mounting a CDROM?</para>
	</question>

	<answer>
	<para>This generally means that there is no CDROM in the
	CDROM drive, or the drive is not visible on the
	bus. Please see the <ulink
	url="&url.books.handbook;/creating-cds.html#MOUNTING-CD">Using Data
	CDs</ulink> section of the Handbook for a detailed
	discussion of this issue.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="cdrom-unicode-filenames">
	<para>Why do all non-English characters in filenames show up as
	<quote>?</quote> on my CDs when mounted in FreeBSD?</para>
	</question>

	<answer>
	<para>Your CDROM probably uses the <quote>Joliet</quote>
	extension for storing information about files and
	directories. This is discussed in the Handbook chapter on
	<ulink url="&url.books.handbook;/creating-cds.html">creating and
	using CDROMs</ulink>, specifically the section on <ulink
	url="&url.books.handbook;/creating-cds.html#MOUNTING-CD">Using Data
	CDROMs</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="burncd-isofs">
	<para>I burned a CD under FreeBSD and now I can not read it
	under any other operating system. Why?</para>
	</question>

	<answer>
	<para>You most likely burned a raw file to your CD, rather
	than creating an ISO 9660 filesystem. Take a look at the
	<ulink url="&url.books.handbook;/creating-cds.html">Handbook
	chapter on creating CDROMs</ulink>, particularly the
	section on <ulink
	url="&url.books.handbook;/creating-cds.html#RAWDATA-CD">burning raw
	data CDs</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="copy-cd">
	<para>How can I create an image of a data CD?</para>
	</question>

	<answer>
	<para>This is discussed in the Handbook section on <ulink
	url="&url.books.handbook;/creating-cds.html#IMAGING-CD">duplicating
	data CDs</ulink>. For more on working with CDROMs, see the
	<ulink url="&url.books.handbook;/creating-cds.html">Creating CDs
	Section</ulink> in the Storage chapter in the
	Handbook.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mount-audio-CD">
	<para>Why can I not <command>mount</command> an audio
	CD?</para>
	</question>

	<answer>
	<para>If you try to mount an audio CD, you will get an error
	like <errorname>cd9660: /dev/acd0c: Invalid
	argument</errorname>. This is because
	<command>mount</command> 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
	<filename role="package">audio/xmcd</filename> port.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="multi-session-CD">
	<para>How do I <command>mount</command> a multi-session CD?</para>
	</question>

	<answer>
	<para>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
	<option>-s</option> command line argument. Please see
	&man.mount.cd9660.8; for specific examples.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="user-floppymount">
	<para>How do I let ordinary users mount floppies, CDROMs and
	other removable media?</para>
	</question>

	<answer>
	<para>Ordinary users can be permitted to mount devices. Here is
	how:</para>

	<procedure>
	<step>
	<para>As <username>root</username> set the sysctl variable
	<varname>vfs.usermount</varname> to
	<literal>1</literal>.</para>

	<screen>&prompt.root; <userinput>sysctl -w vfs.usermount=1</userinput></screen>
	</step>

	<step>
	<para>As <username>root</username> assign the appropriate
	permissions to the block device associated with the
	removable media.</para>

	<para>For example, to allow users to mount the first floppy
	drive, use:</para>

	<screen>&prompt.root; <userinput>chmod 666 /dev/fd0</userinput></screen>

	<para>To allow users in the group
	<groupname>operator</groupname> to mount the CDROM drive,
	use:</para>

	<screen>&prompt.root; <userinput>chgrp operator /dev/acd0c</userinput>
	&prompt.root; <userinput>chmod 640 /dev/acd0c</userinput></screen>
	</step>

	<step>
	<para>If you are running &os; 5.X or later, you will need to alter
	<filename>/etc/devfs.conf</filename> to make these changes
	permanent across reboots.</para>

	<para>As <username>root</username>, add the necessary lines to
	<filename>/etc/devfs.conf</filename>. For example, to allow
	users to mount the first floppy drive add:</para>

	<programlisting># Allow all users to mount the floppy disk.
	own /dev/fd0 root:operator
	perm /dev/fd0 0666</programlisting>

	<para>To allow users in the group <groupname>operator</groupname>
	to mount the CD-ROM drive add:</para>

	<programlisting># Allow members of the group operator to mount CD-ROMs.
	own /dev/acd0 root:operator
	perm /dev/acd0 0660</programlisting>
	</step>

	<step>
	<para>Finally, add the line
	<literal><varname>vfs.usermount</varname>=1</literal>
	to the file <filename>/etc/sysctl.conf</filename> so
	that it is reset at system boot time.</para>
	</step>
	</procedure>

	<para>All users can now mount the floppy
	<devicename>/dev/fd0</devicename> onto a directory that they
	own:</para>

	<screen>&prompt.user; <userinput>mkdir ~/my-mount-point</userinput>
	&prompt.user; <userinput>mount -t msdos /dev/fd0 ~/my-mount-point</userinput></screen>

	<para>Users in group <groupname>operator</groupname> can now
	mount the CDROM <devicename>/dev/acd0c</devicename> onto a
	directory that they own:</para>

	<screen>&prompt.user; <userinput>mkdir ~/my-mount-point</userinput>
	&prompt.user; <userinput>mount -t cd9660 /dev/acd0c ~/my-mount-point</userinput></screen>

	<para>Unmounting the device is simple:</para>

	<screen>&prompt.user; <userinput>umount ~/my-mount-point</userinput></screen>

	<para>Enabling <varname>vfs.usermount</varname>, however,
	has negative security implications. A better way to
	access &ms-dos; formatted media is to use the
	<filename role="package">emulators/mtools</filename>
	package in the ports collection.</para>

	<note>
	<para>The device name used in the previous examples must be
	changed according to your configuration.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="du-vs-df">
	<para>The <command>du</command> and <command>df</command>
	commands show different amounts of disk space available.
	What is going on?</para>
	</question>

	<answer>
	<para>You need to understand what <command>du</command> and
	<command>df</command> really do. <command>du</command>
	goes through the directory tree, measures how large each
	file is, and presents the totals. <command>df</command>
	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 <command>df</command> but not
	<command>du</command>.</para>

	<para>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
	<command>more</command>. Assume you have a file large
	enough that its presence affects the output of
	<command>du</command> and <command>df</command>. (Since
	disks can be so large today, this might be a
	<emphasis>very</emphasis> large file!) If you delete this
	file while using <command>more</command> on it,
	<command>more</command> 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. <command>du</command> shows that it
	is gone — it has walked the directory tree and the file
	is not listed. <command>df</command> shows that it is
	still there, as the filesystem knows that
	<command>more</command> is still using that space. Once
	you end the <command>more</command> session,
	<command>du</command> and <command>df</command> will
	agree.</para>

	<para>Note that Soft Updates can delay the freeing of disk
	space; you might need to wait up to 30 seconds for the
	change to be visible!</para>

	<para>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 <filename>/var</filename>.
	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;.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="add-swap-space">
	<para>How can I add more swap space?</para>
	</question>

	<answer>
	<para>In the <ulink
	url="&url.books.handbook;/config-tuning.html">Configuration and
	Tuning</ulink> section of the Handbook, you will find a
	<ulink
	url="&url.books.handbook;/adding-swap-space.html">section</ulink>
	describing how to do this.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="manufacturer-disk-size">
	<para>Why does &os; see my disk as smaller than the
	manufacturer says it is?</para>
	</question>

	<answer>
	<para>Disk manufacturers calculate gigabytes as a billion bytes
	each, whereas &os; calculates them as 1,073,741,824 bytes
	each. This explains why, for example, &os;'s boot messages
	will report a disk that supposedly has 80GB as holding
	76319MB.</para>
	<para>Also note that &os; will (by default)
	<link linkend="disk-more-than-full">reserve</link> 8% of the disk
	space.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="disk-more-than-full">
	<para>How is it possible for a partition to be more than 100%
	full?</para>
	</question>

	<answer>
	<para>A portion of each UFS partition (8%, by default) is
	reserved for use by the operating system and the
	<username>root</username> user.
	&man.df.1; does not count that space when
	calculating the <literal>Capacity</literal> column, so it can
	exceed 100%. Also, you will notice that the
	<literal>Blocks</literal> column is always greater than the
	sum of the <literal>Used</literal> and
	<literal>Avail</literal> columns, usually by a factor of
	8%.</para>

	<para>For more details, look up the <option>-m</option> option
	in &man.tunefs.8;.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="admin">
	<title>System Administration</title>

	<qandaset>
	<qandaentry>
	<question id="startup-config-files">
	<para>Where are the system start-up configuration files?</para>
	</question>

	<answer>
	<para>The primary configuration file is
	<filename>/etc/defaults/rc.conf</filename> (see
	&man.rc.conf.5;) System startup scripts such as
	<filename>/etc/rc</filename> and
	<filename>/etc/rc.d</filename> (see &man.rc.8;) just
	include this file. <emphasis>Do not edit this
	file!</emphasis> Instead, if there is any entry in
	<filename>/etc/defaults/rc.conf</filename> that you want
	to change, you should copy the line into
	<filename>/etc/rc.conf</filename> and change it
	there.</para>

	<para>For example, if you wish to start named, the included
	DNS server, all you need to do is:</para>

	<screen>&prompt.root; <userinput>echo named_enable="YES" >> /etc/rc.conf</userinput></screen>

	<para>To start up local services, place shell scripts in the
	<filename>/usr/local/etc/rc.d</filename> directory. These
	shell scripts should be set executable, and end with a
	.sh.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="adding-users">
	<para>How do I add a user easily?</para>
	</question>

	<answer>
	<para>Use the &man.adduser.8; command, or the &man.pw.8;
	command for more complicated situations.</para>

	<para>To remove the user, use the &man.rmuser.8; command or,
	if necessary, &man.pw.8;.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="root-not-found-cron-errors">
	<para>Why do I keep getting messages like <errorname>root: not
	found</errorname> after editing my crontab file?</para>
	</question>

	<answer>
	<para>This is normally caused by editing the system crontab
	(<filename>/etc/crontab</filename>) and then using
	&man.crontab.1; to install it:</para>

	<screen>&prompt.root; <userinput>crontab /etc/crontab</userinput></screen>

	<para>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).</para>

	<para>If this is what you did, the extra crontab is simply a
	copy of <filename>/etc/crontab</filename> in the wrong
	format it. Delete it with the command:</para>

	<screen>&prompt.root; <userinput>crontab -r</userinput></screen>

	<para>Next time, when you edit
	<filename>/etc/crontab</filename>, you should not do
	anything to inform &man.cron.8; of the changes, since it
	will notice them automatically.</para>

	<para>If you want something to be run once per day, week, or
	month, it is probably better to add shell scripts
	<filename>/usr/local/etc/periodic</filename>, and let the
	&man.periodic.8; command run from the system cron schedule
	it with the other periodic system tasks.</para>

	<para>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 <username>root</username> for all entries.
	When this crontab is used as the <username>root</username>
	user's crontab (which is <emphasis>not</emphasis> the
	same as the system crontab), &man.cron.8; assumes the string
	<literal>root</literal> is the first word of the command to
	execute, but no such command exists.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="su-wheel-group">
	<para>Why do I get the error, <errorname>you are not in the correct
	group to su root</errorname> when I try to su to
	<username>root</username>?</para>
	</question>

	<answer>
	<para>This is a security feature. In order to su to
	<username>root</username> (or any other account with superuser
	privileges), you must be in the <groupname>wheel</groupname>
	group. If this feature were not there, anybody with an account
	on a system who also found out <username>root</username>'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 <groupname>wheel</groupname>.</para>

	<para>To allow someone to su to <username>root</username>, simply
	put them in the <groupname>wheel</groupname> group.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="rcconf-readonly">
	<para>I made a mistake in <filename>rc.conf</filename>,
	or another startup file, and
	now I cannot edit it because the filesystem is read-only.
	What should I do?</para>
	</question>

	<answer>
	<para>When you get the prompt to enter the shell
	pathname, simply press <literal>ENTER</literal>, and run
	<command>mount /</command> to re-mount the root filesystem in
	read/write mode. You may also need to run <command>mount -a -t
	ufs</command> to mount the filesystem where your favorite
	editor is defined. If your favorite 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;.</para>

	<para>If you intend to use a full screen editor such
	as &man.vi.1; or &man.emacs.1;, you may also need to
	run <command>export TERM=cons25</command> so that these
	editors can load the correct data from the &man.termcap.5;
	database.</para>

	<para>Once you have performed these steps, you can edit
	<filename>/etc/rc.conf</filename> 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="printer-setup">
	<para>Why am I having trouble setting up my printer?</para>
	</question>

	<answer>
	<para>Please have a look at the Handbook entry on printing. It
	should cover most of your problem. See the <ulink
	url="&url.books.handbook;/printing.html">
	Handbook entry on printing</ulink>.</para>

	<para>Some printers require a host-based driver to do any
	kind of printing. These so-called
	<quote>WinPrinters</quote> are not natively supported by
	FreeBSD. If your printer does not work in DOS or &windowsnt;
	4.0, it is probably a WinPrinter. Your only hope of
	getting one of these to work is to check if the <filename
	role="package">print/pnm2ppa</filename> port supports
	it.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="keyboard-mappings">
	<para>How can I correct the keyboard mappings for my system?</para>
	</question>

	<answer>
	<para>Please see the Handbook section on <ulink
	url="&url.books.handbook;/using-localization.html">using
	localization</ulink>, specifically the section on <ulink
	url="&url.books.handbook;/using-localization.html#SETTING-CONSOLE">console
	setup</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="pnp-resources">
	<para>Why do I get messages like: <errorname>unknown: <PNP0303>
	can't assign resources</errorname> on boot?</para>
	</question>

	<answer>
	<para>The following is an excerpt from a post to the
	freebsd-current mailing list.</para>

	<blockquote>
	<attribution>&a.wollman;, 24 April 2001</attribution>

	<para>The <quote>can't assign resources</quote> 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.</para>
	</blockquote>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="user-quotas">
	<para>Why can I not get user quotas to work properly?</para>
	</question>

	<answer>
	<!-- XXX
	This may be the worst answer in the entire document.
	-->
	<orderedlist>
	<listitem>
	<para>It is possible that your kernel is not configured to use
	quotas. If this is the case, you will need to add the following
	line to your kernel configuration file and recompile:</para>
	<programlisting>options QUOTA</programlisting>

	<para>Please read the <ulink url="&url.books.handbook;/quotas.html">Handbook
	entry on quotas</ulink> for full details.</para>
	</listitem>

	<listitem>
	<para>Do not turn on quotas on <filename>/</filename>.</para>
	</listitem>

	<listitem>
	<para>Put the quota file on the filesystem that the quotas
	are to be enforced on, i.e.:</para>

	<informaltable frame="none" pgwide="1">
	<tgroup cols="2">
	<thead>
	<row>
	<entry>Filesystem</entry>
	<entry>Quota file</entry>
	</row>
	</thead>

	<tbody>
	<row>
	<entry><filename>/usr</filename></entry>
	<entry><filename>/usr/admin/quotas</filename></entry>
	</row>

	<row>
	<entry><filename>/home</filename></entry>
	<entry><filename>/home/admin/quotas</filename></entry>
	</row>

	<row>
	<entry>…</entry>
	<entry>…</entry>
	</row>
	</tbody>
	</tgroup>
	</informaltable>
	</listitem>
	</orderedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="sysv-ipc">
	<para>Does FreeBSD support System V IPC primitives?</para>
	</question>

	<answer>
	<para>Yes, FreeBSD supports System V-style IPC, including
	shared memory, messages and semaphores, in the GENERIC
	kernel. In a custom kernel, enable this support by adding
	the following lines to your kernel config.</para>

	<programlisting>options SYSVSHM # enable shared memory
	options SYSVSEM # enable for semaphores
	options SYSVMSG # enable for messaging</programlisting>

	<para>Recompile and install your kernel.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="sendmail-alternative">
	<para>What other mail-server software can I use instead of
	Sendmail?</para>
	</question>

	<answer>
	<para><ulink url="http://www.sendmail.org/">Sendmail</ulink> 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).</para>

	<para>There are various alternative MTAs in the ports tree
	already, with <filename
	role="package">mail/exim</filename>, <filename
	role="package">mail/postfix</filename>, <filename
	role="package">mail/qmail</filename>, and <filename
	role="package">mail/zmailer</filename> being some of the
	most popular choices.</para>

	<para>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 <quote>Is Sendmail better than
	Qmail?</quote> 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 MTAs have already been discussed a few
	times.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="forgot-root-pw">
	<para>I have forgotten the <username>root</username> password! What
	do I do?</para>
	</question><answer>

	<para>Do not panic! Restart the system, type
	<userinput>boot -s</userinput> at the Boot: prompt 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 <command>mount -u /</command> to remount
	your root filesystem read/write, then run <command>mount
	-a</command> to remount all the filesystems. Run
	<command>passwd root</command> to change the
	<username>root</username> password then run &man.exit.1;
	to continue booting.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="CAD-reboot">
	<para>How do I keep <keycombo
	action="simul"><keycap>Control</keycap><keycap>Alt</keycap><keycap>Delete</keycap></keycombo>
	from rebooting the system?</para>
	</question>

	<answer>
	<para>If you are using syscons (the default console driver)
	build and install a new kernel with the
	line:</para>

	<programlisting>options SC_DISABLE_REBOOT</programlisting>

	<para>in the configuration file. If you use the PCVT console
	driver, use the following kernel configuration line
	instead.</para>

	<para>This can also be done by setting the following sysctl
	which does not require a reboot or kernel recompile:</para>

	<screen>&prompt.root; <userinput>sysctl hw.syscons.kbd_reboot=0</userinput></screen>

	<programlisting>options PCVT_CTRL_ALT_DEL</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="dos-to-unix-txt">
	<para>How do I reformat DOS text files to &unix; ones?</para>
	</question>

	<answer>

	<para>Use this perl command:</para>

	<screen>&prompt.user; <userinput>perl -i.bak -npe 's/\r\n/\n/g' file ...</userinput></screen>

	<para>file is the file(s) to process. The modification is done
	in-place, with the original file stored with a .bak
	extension.</para>

	<para>Alternatively you can use the
	&man.tr.1;
	command:</para>

	<screen>&prompt.user; <userinput>tr -d '\r' < <replaceable>dos-text-file</replaceable> > <replaceable>unix-file</replaceable></userinput></screen>

	<para><replaceable>dos-text-file</replaceable> is the file
	containing DOS text while <replaceable>unix-file</replaceable>
	will contain the converted output. This can be quite a bit
	faster than using perl.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="kill-by-name">
	<para>How do I kill processes by name?</para>
	</question><answer>

	<para>Use &man.killall.1;.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="root-acl">
	<para>Why is su bugging me about not being in
	<username>root</username>'s ACL?</para>
	</question>

	<answer>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="uninstall-kerberos">
	<para>How do I uninstall Kerberos?</para>
	</question>

	<answer>

	<para>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</para>

	<screen>&prompt.root; <userinput>cd /cdrom/bin</userinput>
	&prompt.root; <userinput>./install.sh</userinput></screen>

	<para>Alternately, you can remove all
	<makevar>MAKE_KERBEROS</makevar> options from
	<filename>/etc/make.conf</filename> and rebuild
	world.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="where-is-makedev">
	<para>What happened to
	<filename>/dev/MAKEDEV</filename>?</para>
	</question>

	<answer>
	<para>FreeBSD 5.X and beyond use the &man.devfs.8; device-on-demand
	system. Device drivers automatically create new device
	nodes as they are needed, obsoleting
	<filename>/dev/MAKEDEV</filename>.</para>

	<para>If you are running FreeBSD 4.X or earlier and
	<filename>/dev/MAKEDEV</filename> is missing, then you
	really do have a problem. Grab a copy from the system
	source code, probably in
	<filename>/usr/src/etc/MAKEDEV</filename>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="add-pty">
	<para>How do I add pseudoterminals to the system?</para>
	</question>

	<answer>

	<para>If you have lots of telnet, ssh, X, or screen users,
	you will probably run out of pseudoterminals. Here is how to
	add more:</para>

	<procedure>
	<step>
	<para>Build and install a new kernel with the line</para>

	<programlisting>pseudo-device pty 256</programlisting>

	<para>in the configuration file.</para>
	</step>

	<step>
	<para>Run the commands</para>

	<screen>&prompt.root; <userinput>cd /dev</userinput>
	&prompt.root; <userinput>sh MAKEDEV pty{1,2,3,4,5,6,7}</userinput></screen>

	<para>to make 256 device nodes for the new terminals.</para>

	</step>

	<step>
	<para>Edit <filename>/etc/ttys</filename> and add lines
	for each of the 256 terminals. They should match the form
	of the existing entries, i.e. they look like</para>

	<programlisting>ttyqc none network</programlisting>

	<para>The order of the letter designations is
	<literal>tty[pqrsPQRS][0-9a-v]</literal>, using a
	regular expression. </para>
	</step>

	<step>
	<para>Reboot the system with the new kernel and you are
	ready to go.</para>
	</step>
	</procedure>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="create-snd0">
	<para>Why can I not create the snd0 device?</para>
	</question>

	<answer>
	<para>There is no <devicename>snd</devicename> device. The name
	is used as a shorthand for the various devices that make up the
	FreeBSD sound driver, such as <devicename>mixer</devicename>,
	<devicename>sequencer</devicename>, and
	<devicename>dsp</devicename>.</para>

	<para>To create these devices you should</para>

	<screen>&prompt.root; <userinput>cd /dev</userinput>
	&prompt.root; <userinput>sh MAKEDEV snd0</userinput></screen>

	<note>
	<para>You can omit this step if you are running FreeBSD
	5.0-RELEASE or newer with &man.devfs.5;
	enabled.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="reread-rc">
	<para>How do I re-read <filename>/etc/rc.conf</filename> and
	re-start <filename>/etc/rc</filename> without a
	reboot?</para>
	</question>

	<answer>

	<para>Go into single user mode and then back to multi user
	mode.</para>

	<para>On the console do:</para>

	<screen>&prompt.root; <userinput>shutdown now</userinput>
	(Note: without -r or -h)

	&prompt.root; <userinput>return</userinput>
	&prompt.root; <userinput>exit</userinput></screen>
	</answer>
	</qandaentry>


	<qandaentry>
	<question id="release-candidate">
	<para>I tried to update my system to the latest -STABLE, but
	got -BETAx, -RC or -PRERELEASE! What is going on?</para>
	</question>

	<answer>
	<para>Short answer: it is just a name. RC stands for
	<quote>Release Candidate</quote>. 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.)</para>

	<para>Long answer: FreeBSD derives its releases from one of
	two places. Major, dot-zero, releases, such as
	4.0-RELEASE and 5.0-RELEASE, are branched from the head of
	the development stream, commonly referred to as <link
	linkend="current">-CURRENT</link>. Minor releases, such
	as 4.1-RELEASE or 5.2-RELEASE, have been snapshots of the
	active <link linkend="stable">-STABLE</link> 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).</para>

	<para>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.</para>

	<para>For more information on version numbers and the
	various CVS branches, refer to the
	<ulink url="&url.articles.releng;/article.html">Release
	Engineering</ulink> article.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="kernel-chflag-failure">
	<para>I tried to install a new kernel, and the chflags
	failed. How do I get around this?</para>
	</question>

	<answer>
	<para>Short answer: You are probably at security level
	greater than 0. Reboot directly to single user mode to
	install the kernel.</para>

	<para>Long answer: FreeBSD disallows changing system flags
	at security levels greater than 0. You can check your
	security level with the command:</para>

	<screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>

	<para>You cannot lower the security level; you have to boot to
	single mode to install the kernel, or change the security
	level in <filename>/etc/rc.conf</filename> then reboot. See
	the &man.init.8; manual page for details on securelevel, and see
	<filename>/etc/defaults/rc.conf</filename> and the
	&man.rc.conf.5; manual page for more information on
	rc.conf.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="kernel-securelevel-time">
	<para>I cannot change the time on my system by more than one second!
	How do I get around this?</para>
	</question>

	<answer>
	<para>Short answer: You are probably at security level
	greater than 1. Reboot directly to single user mode to
	change the date.</para>

	<para>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:</para>

	<screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>

	<para>You cannot lower the security level; you have to boot
	to single mode to change the date, or change the security
	level in <filename>/etc/rc.conf</filename> then
	reboot. See the &man.init.8; manual page for details on
	securelevel, and see
	<filename>/etc/defaults/rc.conf</filename> and the
	&man.rc.conf.5; manual page for more information on
	rc.conf.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="statd-mem-leak">
	<para>Why is <command>rpc.statd</command> using 256 megabytes of
	memory?</para>
	</question>

	<answer>
	<para>No, there is no memory leak, and it is not using 256 Mbytes
	of memory. For convenience, <command>rpc.statd</command> maps an
	obscene amount of memory into its address space.
	There is nothing terribly wrong with this from a technical
	standpoint; it just throws off things like &man.top.1; and
	&man.ps.1;.</para>

	<para>&man.rpc.statd.8; maps its status file (resident on
	<filename>/var</filename>) 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 <literal>0x10000000</literal>, or one sixteenth of the
	address space on an IA32, or exactly 256MB.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="unsetting-schg">
	<para>Why can I not unset the <literal>schg</literal> file
	flag?</para>
	</question>

	<answer>
	<para>You are running at an elevated (i.e., greater than 0)
	securelevel. Lower the securelevel and try again. For more
	information, see <link linkend="securelevel">the FAQ entry on
	securelevel</link> and the &man.init.8; manual page.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ssh-shosts">
	<para>Why does SSH authentication through
	<filename>.shosts</filename> not work by default in recent
	versions of FreeBSD?</para>
	</question>

	<answer>
	<para>The reason why <filename>.shosts</filename>
	authentication does not work by default in more recent
	versions of FreeBSD is because &man.ssh.1;
	is not installed suid <username>root</username> by default. To
	<quote>fix</quote> this, you can do one of the
	following:</para>

	<itemizedlist>
	<listitem>
	<para>As a permanent fix, set
	<makevar>ENABLE_SUID_SSH</makevar> to <literal>true</literal>
	in <filename>/etc/make.conf</filename> and rebuild ssh
	(or run <command>make world</command>).</para>
	</listitem>

	<listitem>
	<para>As a temporary fix, change the mode on
	<filename>/usr/bin/ssh</filename> to <literal>4555</literal>
	by running <command>chmod 4555 /usr/bin/ssh</command> as
	<username>root</username>. Then add
	<makevar>ENABLE_SUID_SSH= true</makevar> to
	<filename>/etc/make.conf</filename> so the change takes
	effect the next time <command>make world</command> is
	run.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="vnlru">
	<para>What is <literal>vnlru</literal>?</para>
	</question>

	<answer>
	<para><literal>vnlru</literal> flushes and frees vnodes when
	the system hits the <varname>kern.maxvnodes</varname>
	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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="top-memory-states">
	<para>What do the various memory states displayed by
	<command>top</command> mean?</para>
	</question>
	<!-- Provided by John Dyson via Usenet -->
	<answer>
	<itemizedlist>
	<listitem><para><literal>Active</literal>: pages recently
	statistically used.</para></listitem>

	<listitem><para><literal>Inactive</literal>: pages
	recently statistically unused.</para></listitem>

	<listitem><para><literal>Cache</literal>: (most often)
	pages that have percolated from inactive to a status
	where they maintain their data, but can often be
	immediately reused (either with their old association,
	or reused with a new association.) There can be certain
	immediate transitions from <literal>active</literal> to <literal>cache</literal> state if the
	page is known to be clean (unmodified), but that
	transition is a matter of policy, depending upon the
	algorithm choice of the VM system
	maintainer.</para></listitem>

	<listitem><para><literal>Free</literal>: pages without
	data content, and can be immediately used in certain
	circumstances where cache pages might be ineligible.
	Free pages can be reused at interrupt or process
	state.</para></listitem>

	<listitem><para><literal>Wired</literal>: pages that are
	fixed into memory, usually for kernel purposes, but also
	sometimes for special use in
	processes.</para></listitem>
	</itemizedlist>

	<para>Pages are most often written to disk (sort of a VM
	sync) when they are in the inactive state, but active
	pages can also be synced (but requires the
	availability of certain CPU features.) This depends upon
	the CPU tracking of the modified bit being available,
	and in certain situations there can be an advantage for a
	block of VM pages to be synced, whether they are active or
	inactive. In most common cases, it is best to think of
	the inactive queue to be a queue of relatively unused
	pages that might or might not be in the process of being
	written to disk. Cached pages are already synced, not
	mapped, but available for immediate process use with their
	old association or with a new association. Free pages are
	available at interrupt level, but cached or free pages can
	be used at process state for reuse. Cache pages are not
	adequately locked to be available at interrupt
	level.</para>

	<para>There are some other flags (e.g., busy flag or busy
	count) that might modify some of the rules that I
	described.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="free-memory-amount">
	<para>How much free memory is available?</para>
	</question>
	<!-- Provided by John Dyson via Usenet -->
	<answer>
	<para>There are a couple of kinds of <quote>free
	memory</quote>. One kind is the amount of memory
	immediately available without paging anything else out.
	That is approximately the size of cache queue + size of
	free queue (with a derating factor, depending upon system
	tuning.) Another kind of <quote>free memory</quote> is
	the total amount of <acronym>VM</acronym> space. That can
	be complex, but is dependent upon the amount of swap space
	and memory. Other kinds of <quote>free memory</quote>
	descriptions are also possible, but it is relatively
	useless to define these, but rather it is important to
	make sure that the paging rate is kept low, and to avoid
	running out of swap space.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="var-empty">
	<para>What is <filename>/var/empty</filename>? I can not
	delete it!</para>
	</question>

	<answer>
	<para><filename>/var/empty</filename> is a directory that the
	&man.sshd.8; program uses when performing privilege separation.
	The <filename>/var/empty</filename> directory is empty, owned by
	<username>root</username> and has the <literal>schg</literal>
	flag set.</para>

	<para>Although it is not recommended to delete this directory, to
	do so you will need to unset the <literal>schg</literal> flag
	first. See the &man.chflags.1; manual page for more information
	(and bear in mind the answer to <link linkend="unsetting-schg">
	the question on unsetting the schg flag</link>).
	</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="x">
	<title>The X Window System and Virtual Consoles</title>

	<qandaset>
	<qandaentry>
	<question id="whatis-X">
	<para>What is the X Window System?</para>
	</question>

	<answer>

	<para>The X Window System (commonly <literal>X11</literal>) is the
	most widely available windowing system capable of running on
	&unix; or &unix; like systems, including
	&os;. <ulink url= "http://www.x.org">The X.Org
	Foundation</ulink> administers the <ulink
	url="http://en.wikipedia.org/wiki/X_Window_System_core_protocol">
	X protocol standards</ulink>, with the current reference
	implementation, version 11 release &xorg.version;,
	so you will often see references shortened to
	<literal>X11</literal>.
	</para>

	<para>Many implementations are available for different
	architectures and operating systems. An
	implementation of the server-side code is properly known
	as an <literal>X server</literal>.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="which-X">
	<para>Which X implementations are available for &os;?</para>
	</question>

	<answer>

	<para>Historically, the default implementation of X on
	&os; has been
	&xfree86; which is maintained by
	<ulink url="http://www.xfree86.org">The XFree86 Project,
	Inc.</ulink> This software was installed by default on
	&os; versions up until 4.10 and 5.2. Although &xorg;
	itself maintained an implementation during that time
	period, it was basically only provided as a reference
	platform, as it had suffered greatly from bitrot over
	the years.</para>

	<para>However, early in 2004, some XFree86 developers left
	that project
	over issues including the pace of code changes, future
	directions, and interpersonal conflicts, and are now contributing
	code directly to &xorg; instead. At that time, &xorg; updated its
	source tree to the last &xfree86; release before its subsequent
	licensing change (<application>XFree86 version 4.3.99.903</application>), incorporated
	many changes that had previously been maintained separately,
	and has released that software as <application>X11R6.7.0</application>. A separate but
	related project, <ulink url="http://www.freedesktop.org">
	freedesktop.org</ulink> (or <literal>fd.o</literal> for short),
	is working on rearchitecting the original &xfree86; code to
	offload more work onto the graphics cards (with the goal of
	increased performance) and make it more modular
	(with the goal of increased maintainability, and thus faster
	releases as well as easier configuration). &xorg; intends to
	incorporate the freedesktop.org changes in its future releases.</para>

	<para>As of July 2004, in &os.current;,
	&xfree86; has been replaced with &xorg; as the default
	implementation. The &xfree86; ports
	(<filename role="package">x11/XFree86-4</filename> and
	subports) remain in the ports collection. But &xorg; is
	the default X11 implementation for &os; 5.3 and later.</para>

	<para>For further information, read the <ulink
	url="&url.books.handbook;/x11.html">X11</ulink> section of the
	FreeBSD Handbook.</para>

	<note>
	<para>The above describes the default X implementation installed.
	It is still possible to install either implementation by
	following the instructions in the entry for 20040723 in
	<filename>/usr/ports/UPDATING</filename>.</para>
	</note>

	<warning>
	<para>It is not currently
	possible to mix-and-match pieces of each implementation;
	one must choose one or the other.</para>
	</warning>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="xorg-compatibility">
	<para>Will my existing applications run with the &xorg; suite?</para>
	</question>

	<answer>
	<para>The &xorg; software is written to the same X11R6 specification
	that &xfree86; is, so basic applications should work
	unchanged. A few lesser-used protocols have been deprecated
	(<literal>XIE</literal>, <literal>PEX</literal>, and
	<literal>lbxproxy</literal>), but in the first two cases, the
	&os; port of &xfree86; did not support them either.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="xfree86-split">
	<para>Why did the X projects split, anyway?</para>
	</question>

	<answer>
	<para>The answer to this question is outside the scope of
	this FAQ. Note that there are voluminous postings in various
	mailing list archives on the Internet; please use your favorite
	search engine to investigate the history instead of asking this
	question on the &os; mailing lists. It may even be the case
	that only the participants will ever know for certain.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="why-choose-xorg">
	<para>Why did &os; choose to go with the &xorg; ports by default?</para>
	</question>

	<answer>
	<para>The &xorg; developers claim that their goal is to release
	more often and incorporate new features more quickly. If they
	are able to do so, this will be very attractive. Also, their
	software still uses the traditional X license, while &xfree86;
	is now using their modified one.</para>

	<note>
	<para>This decision is still controversial. Only time will
	tell which implementation proves technically superior. Each
	&os; user should decide which they prefer.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="running-X">
	<para>I want to run X, how do I go about it?</para>
	</question>

	<answer>

	<para>If you would like to add X to an existing installation, you
	should use the <filename role="package">x11/xorg</filename>
	meta-port, which will build and install all the necessary
	components.</para>

	<para>Then read and follow the documentation on the
	&man.xorgconfig.1; tool, which assists you in
	configuring &xorg; for your particular graphics
	card/mouse/etc. You may also wish to examine the
	&man.xorgcfg.1; tool, which provides a graphical interface
	to the X configuration process.</para>

	<para>For further information, read the <ulink
	url="&url.books.handbook;/x11.html">X11</ulink> section of the
	FreeBSD Handbook.</para>

	<para>You may also wish to investigate the Xaccel server.
	See the section on <link linkend="xig">Xi Graphics</link>
	for more details.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="running-X-securelevels">
	<para>I <emphasis>tried</emphasis> to run X, but I get an
	<errorname>KDENABIO failed (Operation not permitted)</errorname>
	error when I type <command>startx</command>. What do I do
	now?</para>
	</question>

	<answer>
	<para>Your system is probably running at a raised securelevel.
	It is not possible to start X at a raised securelevel because
	X requires write access to <devicename>/dev/io</devicename>.
	For more information, see at the &man.init.8; manual
	page.</para>

	<para>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 <filename>/etc/rc.conf</filename>),
	or run &man.xdm.1; at boot time (before the securelevel is
	raised).</para>

	<para>See <xref linkend="xdm-boot"> for more information about
	running &man.xdm.1; at boot time.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="x-and-moused">
	<para>Why does my mouse not work with X?</para>
	</question>

	<answer>
	<para>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
	<devicename>/dev/sysmouse</devicename>. 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, <emphasis>and</emphasis> use X, see
	<xref linkend="moused" remap="another section"> and set up
	moused.</para>

	<para>Then edit <filename>/etc/X11/xorg.conf</filename> and make
	sure you have the following lines:</para>

	<programlisting>Section "InputDevice"
	Option "Protocol" "SysMouse"
	Option "Device" "/dev/sysmouse"
	.....</programlisting>

	<para>Some people prefer to use
	<devicename>/dev/mouse</devicename> under X. To make this
	work, <devicename>/dev/mouse</devicename> should be linked
	to <devicename>/dev/sysmouse</devicename> (see
	&man.sysmouse.4;):</para>

	<screen>&prompt.root; <userinput>cd /dev</userinput>
	&prompt.root; <userinput>rm -f mouse</userinput>
	&prompt.root; <userinput>ln -s sysmouse mouse</userinput></screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="x-and-wheel">
	<para>My mouse has a fancy wheel. Can I use it in X?</para>
	</question>

	<answer>
	<para>Yes.</para>

	<para>You need to tell X that you have a 5 button mouse.
	To do this, simply add the lines
	<literal>Buttons 5</literal> and
	<literal>ZAxisMapping 4 5</literal> to the
	<quote>InputDevice</quote> section of
	<filename>/etc/X11/xorg.conf</filename>. For example, you
	might have the following <quote>InputDevice</quote> section
	in <filename>/etc/X11/xorg.conf</filename>.</para>

	<example>
	<title><quote>InputDevice</quote> Section for Wheeled Mouse
	in &xorg; configuration file</title>

	<programlisting>Section "InputDevice"
	Identifier "Mouse1"
	Driver "mouse"
	Option "Protocol" "auto"
	Option "Device" "/dev/sysmouse"
	Option "Buttons" "5"
	Option "ZAxisMapping" "4 5"
	EndSection</programlisting>
	</example>

	<example>
	<title><quote>.emacs</quote> example for naive page
	scrolling with Wheeled Mouse (optional)</title>
	<programlisting>;; wheel mouse
	(global-set-key [mouse-4] 'scroll-down)
	(global-set-key [mouse-5] 'scroll-up)</programlisting>
	</example>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="no-remote-x11">
	<para>How do I use remote X displays?</para>
	</question>

	<answer>
	<para>For security reasons, the default setting is to not allow a
	machine to remotely open a window.</para>

	<para>To enable this feature, simply start
	<application>X</application> with the optional
	<option>-listen_tcp</option> argument:</para>
	<screen>&prompt.user; <userinput>startx -listen_tcp</userinput>
	</screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="window-menu-weird">
	<para>Why do X Window menus and dialog boxes not work
	right?</para>
	</question>

	<answer>
	<para>Try turning off the <keycap>Num Lock</keycap> key.</para>

	<para>If your <keycap>Num Lock</keycap> key is on by default
	at boot-time, you may add the following line in the
	<literal>Keyboard</literal> section of the
	<filename>/etc/X11/xorg.conf</filename> file.</para>

	<programlisting># Let the server do the NumLock processing. This should only be
	# required when using pre-R6 clients
	ServerNumLock</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="virtual-console">
	<para>What is a virtual console and how do I make more?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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.</para>

	<para>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 <keycombo
	action="simul"><keycap>Alt</keycap><keycap>F2</keycap></keycombo>
	(hold down the <keycap>Alt</keycap> key and press the
	<keycap>F2</keycap> key), and you will find a login prompt
	waiting for you on the second <quote>virtual
	console</quote>! When you want to go back to the original
	session, do <keycombo
	action="simul"><keycap>Alt</keycap><keycap>F1</keycap></keycombo>.</para>

	<para>The default FreeBSD installation has eight virtual
	consoles enabled. <keycombo
	action="simul"><keycap>Alt</keycap><keycap>F1</keycap></keycombo>,
	<keycombo
	action="simul"><keycap>Alt</keycap><keycap>F2</keycap></keycombo>,
	<keycombo
	action="simul"><keycap>Alt</keycap><keycap>F3</keycap></keycombo>,
	and so on will switch between these virtual
	consoles.</para>

	<para>To enable more of them, edit
	<filename>/etc/ttys</filename> (see &man.ttys.5;)
	and add entries for <devicename>ttyv4</devicename>
	to <devicename>ttyvc</devicename> after the comment on
	<quote>Virtual terminals</quote>:</para>

	<programlisting># 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</programlisting>

	<para>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 <literal>secure</literal>
	to <literal>insecure</literal>.</para>

	<important>
	<para>If you want to run an X server you
	<emphasis>must</emphasis> 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.</para>
	</important>

	<para>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:</para>

	<programlisting>ttyvb "/usr/libexec/getty Pc" cons25 on secure</programlisting>

	<para>to:</para>

	<programlisting>ttyvb "/usr/libexec/getty Pc" cons25 off secure</programlisting>

	<para>If your keyboard has only ten function keys, you would
	end up with:</para>

	<programlisting>ttyv9 "/usr/libexec/getty Pc" cons25 off secure
	ttyva "/usr/libexec/getty Pc" cons25 off secure
	ttyvb "/usr/libexec/getty Pc" cons25 off secure</programlisting>

	<para>(You could also just delete these lines.)</para>

	<para>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 <username>root</username>):</para>

	<screen>&prompt.root; <userinput>kill -HUP 1</userinput></screen>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="vty-from-x">
	<para>How do I access the virtual consoles from X?</para>
	</question>

	<answer>
	<para>Use <keycombo action="simul">
	<keycap>Ctrl</keycap>
	<keycap>Alt</keycap>
	<keycap>F<replaceable>n</replaceable></keycap>
	</keycombo> to switch back to a virtual console.
	<keycombo action="simul">
	<keycap>Ctrl</keycap>
	<keycap>Alt</keycap>
	<keycap>F1</keycap>
	</keycombo> would return you to the first virtual console.</para>

	<para>Once you are back to a text console, you can then use
	<keycombo action="simul">
	<keycap>Alt</keycap>
	<keycap>F<replaceable>n</replaceable></keycap>
	</keycombo> as normal to move between them.</para>

	<para>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 <command>startx</command>) 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
	<keycombo action="simul">
	<keycap>Alt</keycap>
	<keycap>F9</keycap>
	</keycombo> to return.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="xdm-boot">
	<para>How do I start XDM on boot?</para>
	</question><answer>

	<para>There are two schools of thought on how to start
	&man.xdm.1;. One school starts xdm from
	<filename>/etc/ttys</filename> (see &man.ttys.5;) using
	the supplied example, while the other simply runs xdm from
	<filename>rc.local</filename> (see &man.rc.8;) or from a
	<filename>X.sh</filename> script in
	<filename>/usr/local/etc/rc.d</filename>. 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.</para>

	<para>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.</para>

	<para>If loaded from rc.local, <command>xdm</command> 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.</para>

	<para>If you are to start <command>xdm</command> from
	<filename>/etc/ttys</filename>, there still is a chance of
	conflict between <command>xdm</command> and
	&man.getty.8;. One way to avoid this is to add the
	<literal>vt</literal> number in the
	<filename>/usr/local/lib/X11/xdm/Xservers</filename>
	file.</para>

	<programlisting>:0 local /usr/local/bin/X vt4</programlisting>

	<para>The above example will direct the X server to run in
	<devicename>/dev/ttyv3</devicename>. Note the number is offset by
	one. The X server counts the vty from one, whereas the FreeBSD
	kernel numbers the vty from zero.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="xconsole-failure">
	<para>Why do I get <errorname>Couldn't open console</errorname>
	when I run xconsole?</para>
	</question>

	<answer>
	<para>If you start <application>X</application>
	with
	<command>startx</command>, the permissions on
	<devicename>/dev/console</devicename> will
	<emphasis>not</emphasis> get changed, resulting in
	things like
	<command>xterm -C</command> and
	<command>xconsole</command> not working.</para>

	<para>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.</para>

	<para>In a nutshell, make sure an uncommented line of the
	form</para>

	<programlisting>/dev/ttyv0 0600 /dev/console</programlisting>

	<para>is in <filename>/etc/fbtab</filename> (see
	&man.fbtab.5;) and it will ensure that whomever logs in on
	<devicename>/dev/ttyv0</devicename> will own the
	console.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="xfree86-root">
	<para>Before, I was able to run &xfree86; as a regular user. Why does
	it now say that I must be <username>root</username>?</para>
	</question>

	<answer>
	<para>All X servers need to be run as
	<username>root</username> 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 <username>root</username> (setuid to
	<username>root</username>). This is obviously a security
	hazard because X servers are large, complicated programs.
	Newer versions of &xfree86; do not install the servers
	setuid to <username>root</username> for just this
	reason.</para>

	<para>Obviously, running an X server as the
	<username>root</username> 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
	<command>xdm</command> or another display manager (e.g.,
	<command>kdm</command>); the second is to use the
	<command>Xwrapper</command>.</para>

	<para><command>xdm</command> 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 <command>xdm</command> see
	<ulink url="http://www.xfree86.org/sos/resources.html">the &xfree86;
	documentation</ulink>, and the <link linkend="xdm-boot">the FAQ
	entry</link> on it.</para>

	<para><command>Xwrapper</command> 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
	manager for whatever reason, this is for you. If you have
	installed the complete ports collection, you can find the port in
	<filename>/usr/ports/x11/wrapper</filename>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ps2-x">
	<para>Why does my PS/2 mouse misbehave under X?</para>
	</question>

	<answer>
	<para>Your mouse and the mouse driver may have somewhat become
	out of synchronization.</para>

	<para>
	In rare cases the driver may erroneously report
	synchronization problem and you may see the kernel
	message:</para>

	<programlisting>psmintr: out of sync (xxxx != yyyy)</programlisting>

	<para>and notice that your mouse does not work properly.</para>

	<para>If this happens, disable the synchronization check code
	by setting the driver flags for the PS/2 mouse driver to 0x100.
	Enter <emphasis>UserConfig</emphasis> by giving the
	<option>-c</option> option at the boot prompt:</para>

	<screen>boot: <userinput>-c</userinput></screen>

	<para>Then, in the <emphasis>UserConfig</emphasis> command
	line, type:</para>

	<screen>UserConfig> <userinput>flags psm0 0x100</userinput>
	UserConfig> <userinput>quit</userinput></screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ps2-mousesystems">
	<para>Why does my PS/2 mouse from MouseSystems not
	work?</para>
	</question>

	<answer>
	<para>There have been some reports that certain model of PS/2
	mouse from MouseSystems works only if it is put into the
	<quote>high resolution</quote> mode. Otherwise, the mouse
	cursor may jump to the upper-left corner of the screen every
	so often.</para>

	<para>Specify the flags 0x04 to the PS/2 mouse driver to put
	the mouse into the high resolution mode. Enter
	<emphasis>UserConfig</emphasis> by giving the
	<option>-c</option> option at the boot prompt:</para>

	<screen>boot: <userinput>-c</userinput></screen>

	<para>Then, in the <emphasis>UserConfig</emphasis> command line,
	type:</para>

	<screen>UserConfig> <userinput>flags psm0 0x04</userinput>
	UserConfig> <userinput>quit</userinput></screen>

	<para>See the previous section for another possible cause of mouse
	problems.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="xfree86-version">
	<para>I want to install different X server.</para>
	</question>

	<answer>
	<para>&os; versions prior 5.3 will use the default
	<application>&xfree86; 4.X</application>,
	while latter versions will default to
	<application>&xorg;</application>.
	If you want to run a different X11 implementation
	than the default one, add the following line to
	<filename>/etc/make.conf</filename>, (if you
	do not have this file, create it):</para>

	<programlisting>X_WINDOW_SYSTEM= xorg</programlisting>

	<para>This variable may be set to <literal>xorg</literal>,
	<literal>xfree86-4</literal>, or
	<literal>xfree86-3</literal>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mouse-button-reverse">
	<para>How do I reverse the mouse buttons?</para>
	</question>

	<answer>
	<para>Run the command
	<command>xmodmap -e "pointer = 3 2 1"</command> from your
	<filename>.xinitrc</filename> or <filename>.xsession</filename>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="install-splash">
	<para>How do I install a splash screen and where do I find
	them?</para>
	</question>

	<answer>

	<para>&os; have a feature to allow the display of
	<quote>splash</quote> screens during the boot
	messages. The splash screens currently must be a 256 color
	bitmap (<filename>*.BMP</filename>) or ZSoft PCX
	(<filename>*.PCX</filename>) 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.
	The actual VESA support can either be compiled directly
	into the kernel with the <literal>VESA</literal> kernel
	config option or by loading the VESA kld module during
	bootup.</para>

	<para>To use a splash screen, you need to modify the startup
	files that control the boot process for &os;.</para>

	<para>You need to create
	a <filename>/boot/loader.rc</filename> file that contains
	the following lines:</para>

	<programlisting>include /boot/loader.4th
	start</programlisting>

	<para>and a <filename>/boot/loader.conf</filename> that
	contains the following:</para>

	<programlisting>splash_bmp_load="YES"
	bitmap_load="YES"</programlisting>

	<para>This assumes you are using
	<filename>/boot/splash.bmp</filename> for your splash
	screen. If you would rather use a PCX file, copy it to
	<filename>/boot/splash.pcx</filename>, create a
	<filename>/boot/loader.rc</filename> as instructed above,
	and create a <filename>/boot/loader.conf</filename> that
	contains:</para>

	<programlisting>splash_pcx_load="YES"
	bitmap_load="YES"
	bitmap_name="/boot/splash.pcx"</programlisting>

	<para>Now all you need is a splash screen. For that you can
	surf on over to the gallery at
	<ulink url="http://www.baldwin.cx/splash/"></ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="windows-keys">
	<para>Can I use the &windows;
	keys on my keyboard in X?</para>
	</question>

	<answer>
	<para>Yes. All you need to do is use &man.xmodmap.1; to define
	what function you wish them to perform.</para>

	<para>Assuming all <quote>&windows;</quote> keyboards
	are standard then the keycodes for the 3 keys are</para>

	<itemizedlist>
	<listitem>
	<para>115 - &windows; key, between
	the left-hand Ctrl and Alt keys</para>
	</listitem>

	<listitem>
	<para>116 - &windows; key, to the
	right of the <keycap>AltGr</keycap> key</para>
	</listitem>

	<listitem>
	<para>117 - <keycap>Menu</keycap> key, to the left of
	the right-hand <keycap>Ctrl</keycap> key</para>
	</listitem>
	</itemizedlist>

	<para>To have the left &windows; key print a comma,
	try this.</para>

	<screen>&prompt.root; <userinput>xmodmap -e "keycode 115 = comma"</userinput></screen>

	<para>You will probably have to re-start your window manager
	to see the result.</para>

	<para>To have the &windows;
	key-mappings enabled automatically every time you start X either
	put the <command>xmodmap</command> commands in your
	<filename>~/.xinitrc</filename> file or, preferably, create a file
	<filename>~/.xmodmaprc</filename> and include the
	<command>xmodmap</command> options, one per line, then add the
	line</para>

	<programlisting>xmodmap $HOME/.xmodmaprc</programlisting>

	<para>to your <filename>~/.xinitrc</filename>.</para>

	<para>For example, you could map the 3 keys to be
	<keycap>F13</keycap>, <keycap>F14</keycap>, and
	<keycap>F15</keycap>, respectively. This would make it
	easy to map them to useful functions within applications
	or your window manager, as demonstrated further
	down.</para>

	<para>To do this put the following in
	<filename>~/.xmodmaprc</filename>.</para>

	<programlisting>keycode 115 = F13
	keycode 116 = F14
	keycode 117 = F15</programlisting>

	<para>If you use <command>fvwm2</command>, for example, you
	could map the keys so that <keycap>F13</keycap> iconifies
	(or de-iconifies) the window the cursor is in,
	<keycap>F14</keycap> brings the window the cursor is in to
	the front or, if it is already at the front, pushes it to
	the back, and <keycap>F15</keycap> 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).</para>

	<para>The following entries in
	<filename>~/.fvwmrc</filename> implement the
	aforementioned setup:</para>

	<programlisting>Key F13 FTIWS A Iconify
	Key F14 FTIWS A RaiseLower
	Key F15 A A Menu Workplace Nop</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="x-3d-acceleration">
	<para>How can I get 3D hardware acceleration for
	&opengl;?</para>
	</question>

	<answer>
	<para>The availability of 3D acceleration depends on the
	version of &xfree86; or &xorg; that you are using and the type of video chip
	you have. If you have an NVIDIA chip, you can use the binary
	drivers provided for FreeBSD on the
	<ulink url="http://www.nvidia.com/content/drivers/drivers.asp">
	Drivers</ulink> section of their website. For other cards
	with &xfree86;-4 or &xorg;, 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
	<ulink
	url="http://people.FreeBSD.org/~anholt/dri/">XFree86-4
	Direct Rendering on FreeBSD</ulink> page.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="networking">
	<title>Networking</title>

	<qandaset>
	<qandaentry>
	<question id="diskless-booting">
	<para>Where can I get information on
	<quote>diskless booting</quote>?</para>
	</question>

	<answer>
	<para><quote>Diskless booting</quote> 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 <ulink url="&url.books.handbook;/network-diskless.html">the
	Handbook entry on diskless booting</ulink></para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="router">
	<para>Can a FreeBSD box be used as a dedicated network
	router?</para>
	</question>

	<answer>
	<para>Yes. Please see the Handbook entry on <ulink
	url="&url.books.handbook;/advanced-networking.html"> advanced
	networking</ulink>, specifically the section on <ulink
	url="&url.books.handbook;/network-routing.html">routing
	and gateways</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="win95-connection">
	<para>Can I connect my &windows; box to the Internet via
	FreeBSD?</para>
	</question>

	<answer>
	<para>Typically, people who ask this question have two PCs
	at home, one with FreeBSD and one with some version of
	&windows; the idea is to use the FreeBSD box to connect to
	the Internet and then be able to access the Internet from
	the &windows; box through the FreeBSD box. This is really
	just a special case of the previous question and works
	perfectly well.</para>

	<para>If you are using dialup to connect to the Internet
	user-mode &man.ppp.8; contains a <option>-nat</option>
	option. If you run &man.ppp.8; with the
	<option>-nat</option> option, set
	<literal>gateway_enable</literal> to
	<emphasis>YES</emphasis> in
	<filename>/etc/rc.conf</filename>, and configure your
	&windows; machine correctly, this should work fine. For more
	information, please see the &man.ppp.8; manual page or the
	<ulink url="&url.books.handbook;/userppp.html">Handbook entry on
	user PPP</ulink>.</para>

	<para>If you are using kernel-mode PPP or have an Ethernet
	connection to the Internet, you need to use
	&man.natd.8;. Please look at the <ulink
	url="&url.books.handbook;/network-natd.html">natd</ulink> section
	of the Handbook for a tutorial.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="slip-ppp-support">
	<para>Does FreeBSD support SLIP and PPP?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>For more information on how to use these, please see the
	<ulink url="&url.books.handbook;/ppp-and-slip.html">Handbook chapter on
	PPP and SLIP</ulink>.</para>

	<para>If you only have access to the Internet through a
	<quote>shell account</quote>, you may want to have a look
	at the <filename role="package">net/slirp</filename>
	package. It can provide you with (limited) access to
	services such as ftp and http direct from your local
	machine.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="natd">
	<para>Does FreeBSD support NAT or Masquerading?</para>
	</question>

	<answer>
	<para>Yes. If you want to use NAT over a user PPP
	connection, please see the <ulink
	url="&url.books.handbook;/userppp.html">Handbook entry on user
	PPP</ulink>. If you want to use NAT over some other sort
	of network connection, please look at the <ulink
	url="&url.books.handbook;/network-natd.html">natd</ulink> section
	of the Handbook.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="parallel-connect">
	<para>How do I connect two FreeBSD systems over a parallel line
	using PLIP?</para>
	</question>

	<answer>
	<para>Please see the <ulink url="&url.books.handbook;/network-plip.html">PLIP
	section</ulink> of the Handbook.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="create-dev-net">
	<para>Why can I not create a <devicename>/dev/ed0</devicename>
	device?</para>
	</question>

	<answer>
	<para>Because they are not necessary. In the Berkeley
	networking framework, network interfaces are only directly
	accessible by kernel code. Please see the
	<filename>/etc/rc.network</filename> 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ethernet-aliases">
	<para>How can I set up Ethernet aliases?</para>
	</question>

	<answer>
	<para>If the alias is on the same subnet as an address
	already configured on the interface, then add
	<literal>netmask 0xffffffff</literal> to your
	&man.ifconfig.8; command-line, as in the following:</para>

	<screen>&prompt.root; <userinput>ifconfig ed0 alias 192.0.2.2 netmask 0xffffffff</userinput></screen>

	<para>Otherwise, just specify the network address and
	netmask as usual:</para>

	<screen>&prompt.root; <userinput>ifconfig ed0 alias 172.16.141.5 netmask 0xffffff00</userinput></screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="port-3c503">
	<para>How do I get my 3C503 to use the other network
	port?</para>
	</question>

	<answer>
	<para>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
	<literal>link0</literal>. To use the AUI port instead of the
	BNC one, use <literal>link2</literal>. These flags should be
	specified using the ifconfig_* variables in
	<filename>/etc/rc.conf</filename> (see &man.rc.conf.5;).</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="nfs">
	<para>Why am I having trouble with NFS and FreeBSD?</para>
	</question>

	<answer>
	<para>Certain PC network cards are better than others (to put
	it mildly) and can sometimes cause problems with network
	intensive applications like NFS.</para>

	<para>See <ulink url="&url.books.handbook;/network-nfs.html">
	the Handbook entry on NFS</ulink> for more information on
	this topic.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="nfs-linux">
	<para>Why can I not NFS-mount from a &linux; box?</para>
	</question>

	<answer>
	<para>Some versions of the &linux; NFS code only accept mount
	requests from a privileged port; try</para>

	<screen>&prompt.root; <userinput>mount -o -P linuxbox:/blah /mnt</userinput></screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="nfs-sun">
	<para>Why can I not NFS-mount from a Sun box?</para>
	</question>

	<answer>
	<para>&sun; workstations running &sunos; 4.X only accept mount
	requests from a privileged port; try</para>

	<screen>&prompt.root; <userinput>mount -o -P sunbox:/blah /mnt</userinput></screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="exports-errors">
	<para>Why does <command>mountd</command> keep telling me it
	<errorname>can't change attributes</errorname> and that I have a
	<errorname>bad exports list</errorname> on my FreeBSD NFS
	server?</para>
	</question>

	<answer>
	<para>The most frequent problem is not understanding the
	correct format of <filename>/etc/exports</filename>.
	Please review &man.exports.5; and the <ulink
	url="&url.books.handbook;/network-nfs.html">NFS</ulink> entry in the
	Handbook, especially the section on <ulink
	url="&url.books.handbook;/network-nfs.html#CONFIGURING-NFS">configuring
	NFS</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-nextstep">
	<para>Why am I having problems talking PPP to NeXTStep
	machines?</para>
	</question>

	<answer>

	<para>Try disabling the TCP extensions in
	<filename>/etc/rc.conf</filename> (see &man.rc.conf.5;) by
	changing the following variable to NO:</para>

	<programlisting>tcp_extensions=NO</programlisting>

	<para>Xylogic's Annex boxes are also broken in this regard
	and you must use the above change to connect through
	them.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ip-multicast">
	<para>How do I enable IP multicast support?</para>
	</question>

	<answer>
	<para>FreeBSD supports multicast host operations by
	default. If you want your box to run as a multicast
	router, you need to recompile your kernel with the
	<literal>MROUTING</literal> option and run
	&man.mrouted.8;. FreeBSD will start &man.mrouted.8; at
	boot time if the flag <literal>mrouted_enable</literal> is
	set to <literal>"YES"</literal> in
	<filename>/etc/rc.conf</filename>.</para>

	<para>MBONE tools are available in their own ports category,
	<ulink
	url="http://www.FreeBSD.org/ports/mbone.html">mbone</ulink>.
	If you are looking for the conference tools
	<command>vic</command> and <command>vat</command>, look
	there!</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="dec-pci-chipset">
	<para>Which network cards are based on the DEC PCI
	chipset?</para>
	</question><answer>

	<para>Here is a list compiled by Glen Foster
	<email>gfoster@driver.nsta.org</email>,
	with some more modern additions:</para>

	<table>
	<title>Network cards based on the DEC PCI chipset</title>

	<tgroup cols=2>
	<thead>
	<row>
	<entry>Vendor</entry>
	<entry>Model</entry>
	</row>
	</thead>

	<tbody>
	<row>
	<entry>ASUS</entry>
	<entry>PCI-L101-TB</entry>
	</row>
	<row>
	<entry>Accton</entry>
	<entry>ENI1203</entry>
	</row>
	<row>
	<entry>Cogent</entry>
	<entry>EM960PCI</entry>
	</row>
	<row>
	<entry>Compex</entry>
	<entry>ENET32-PCI</entry>
	</row>
	<row>
	<entry>D-Link</entry>
	<entry>DE-530</entry>
	</row>
	<row>
	<entry>Dayna</entry>
	<entry>DP1203, DP2100</entry>
	</row>
	<row>
	<entry>DEC</entry>
	<entry>DE435, DE450</entry>
	</row>
	<row>
	<entry>Danpex</entry>
	<entry>EN-9400P3</entry>
	</row>
	<row>
	<entry>JCIS</entry>
	<entry>Condor JC1260</entry>
	</row>
	<row>
	<entry>Linksys</entry>
	<entry>EtherPCI</entry>
	</row>
	<row>
	<entry>Mylex</entry>
	<entry>LNP101</entry>
	</row>
	<row>
	<entry>SMC</entry>
	<entry>EtherPower 10/100 (Model 9332)</entry>
	</row>
	<row>
	<entry>SMC</entry>
	<entry>EtherPower (Model 8432)</entry>
	</row>
	<row>
	<entry>TopWare</entry>
	<entry>TE-3500P</entry>
	</row>
	<row>
	<entry>Znyx (2.2.x)</entry>
	<entry>ZX312, ZX314, ZX342, ZX345, ZX346, ZX348</entry>
	</row>
	<row>
	<entry>Znyx (3.x)</entry>
	<entry>ZX345Q, ZX346Q, ZX348Q, ZX412Q, ZX414, ZX442, ZX444,
	ZX474, ZX478, ZX212, ZX214 (10mbps/hd)</entry>
	</row>
	</tbody>
	</tgroup>
	</table>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="fqdn-hosts">
	<para>Why do I have to use the FQDN for hosts on my
	site?</para>
	</question>

	<answer>
	<para>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 <hostid>mumble</hostid> in the
	<hostid role="domainname">example.org</hostid> domain, you will
	have to refer to it by the fully-qualified domain name, <hostid
	role="fqdn">mumble.example.org</hostid>, instead of just
	<hostid>mumble</hostid>.</para>

	<para>Traditionally, this was allowed by BSD BIND resolvers.
	However the current version of
	<application>bind</application> (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
	<hostid>mumble</hostid> must either be found as <hostid
	role="fqdn">mumble.foo.example.org</hostid>, or it will be searched
	for in the root domain.</para>

	<para>This is different from the previous behavior, where the
	search continued across
	<hostid role="domainname">mumble.example.org</hostid>, and
	<hostid role="domainname">mumble.edu</hostid>. Have a look at
	RFC 1535 for why this was considered bad practice, or even a
	security hole.</para>

	<para>As a good workaround, you can place the line</para>

	<programlisting>search foo.example.org example.org</programlisting>

	<para>instead of the previous</para>

	<programlisting>domain foo.example.org</programlisting>

	<para>into your <filename>/etc/resolv.conf</filename> file
	(see &man.resolv.conf.5;). However, make sure that the
	search order does not go beyond the <quote>boundary
	between local and public administration</quote>, as RFC
	1535 calls it.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="network-permission-denied">
	<para>Why do I get an error, <errorname>Permission
	denied</errorname>, for all networking operations?</para>
	</question>

	<answer>
	<para>If you have compiled your kernel with the
	<literal>IPFIREWALL</literal> option, you need to be aware
	that the default policy is to deny all packets that are
	not explicitly allowed.</para>

	<para>If you had unintentionally misconfigured your system
	for firewalling, you can restore network operability by
	typing the following while logged in as
	<username>root</username>:</para>

	<screen>&prompt.root; <userinput>ipfw add 65534 allow all from any to any</userinput></screen>

	<para>You can also set
	<literal>firewall_type="open"</literal> in
	<filename>/etc/rc.conf</filename>.</para>

	<para>For further information on configuring a FreeBSD
	firewall, see the <ulink url="&url.books.handbook;/firewalls.html">
	Handbook chapter</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ipfw-overhead">
	<para>How much overhead does IPFW incur?</para>
	</question>

	<answer>
	<para>Please see the Handbook's <ulink
	url="&url.books.handbook;/firewalls.html">Firewalls</ulink>
	section, specifically the section on <ulink
	url="&url.books.handbook;/firewalls.html#IPFW-OVERHEAD">IPFW
	Overhead & Optimization</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ipfw-fwd">
	<para>Why is my <command>ipfw</command> <quote>fwd</quote> rule
	to redirect a service to another machine not working?</para>
	</question>

	<answer>
	<para>Possibly because you want to do network address translation
	(NAT) and not just forward packets. A <quote>fwd</quote> 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:</para>

	<screen>01000 fwd <replaceable>10.0.0.1</replaceable> from any to <replaceable>foo 21</replaceable></screen>

	<para>When a packet with a destination address of
	<replaceable>foo</replaceable> arrives at the machine with this
	rule, the packet is forwarded to
	<replaceable>10.0.0.1</replaceable>, but it still has the
	destination address of <replaceable>foo</replaceable>! The
	destination address of the packet is <emphasis>not</emphasis>
	changed to <replaceable>10.0.0.1</replaceable>. Most machines
	would probably drop a packet that they receive with a
	destination address that is not their own. Therefore, using a
	<quote>fwd</quote> rule does not often work the way the user
	expects. This behavior is a feature and not a bug.</para>

	<para>See the <link linkend="service-redirect">FAQ about
	redirecting services</link>, the &man.natd.8; manual, or one of
	the several port redirecting utilities in the <ulink
	url="&url.base;/ports/index.html">ports collection</ulink> for a correct way to do
	this.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="service-redirect">
	<para>How can I redirect service requests from one machine to
	another?</para>
	</question>

	<answer>
	<para>You can redirect FTP (and other service) request with
	the <literal>socket</literal> package, available in the ports
	tree in category <quote>sysutils</quote>. Simply replace the
	service's command line to call socket instead, like so:</para>

	<programlisting>ftp stream tcp nowait nobody /usr/local/bin/socket socket <replaceable>ftp.example.com</replaceable> <replaceable>ftp</replaceable></programlisting>

	<para>where <replaceable>ftp.example.com</replaceable> and
	<replaceable>ftp</replaceable> are the host and port to
	redirect to, respectively.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="bandwidth-mgr-tool">
	<para>Where can I get a bandwidth management tool?</para>
	</question>

	<answer>
	<para>There are three bandwidth management tools available
	for FreeBSD. &man.dummynet.4; is integrated into FreeBSD
	as part of &man.ipfw.4;. <ulink
	url="http://www.csl.sony.co.jp/person/kjc/programs.html">ALTQ</ulink>
	is available for free on FreeBSD 4.X and has been
	integrated into FreeBSD 5.X as part of &man.pf.4;.
	Bandwidth Manager from <ulink
	url="http://www.etinc.com/">Emerging Technologies</ulink>
	is a commercial product.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="bpf-not-configured">
	<para>Why do I get <errorname>/dev/bpf0: device not
	configured</errorname>?</para>
	</question>

	<answer>
	<para>You are running a program that requires the Berkeley
	Packet Filter (&man.bpf.4;), but it is not in your kernel.
	Add this to your kernel config file and build a new
	kernel:</para>

	<programlisting>pseudo-device bpf # Berkeley Packet Filter</programlisting>

	<para>On FreeBSD 4.X and earlier, you must also create the
	device node. After rebooting, go to the
	<filename>/dev</filename> directory and run:</para>

	<screen>&prompt.root; <userinput>sh MAKEDEV bpf0</userinput></screen>

	<para>Please see the <ulink
	url="&url.books.handbook;/kernelconfig-nodes.html"> Handbook entry
	on device nodes</ulink> for more information on managing
	devices.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="mount-smb-share">
	<para>How do I mount a disk from a &windows; machine that is on my
	network, like smbmount in &linux;?</para>
	</question>

	<answer>
	<para>Use the <application>SMBFS</application> toolset. It
	includes a set of kernel modifications and a set of
	userland programs. The programs and information are
	available as <filename role="package">net/smbfs</filename>
	in the ports collection, or in the base system as of
	4.5-RELEASE and later.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="icmp-response-bw-limit">
	<para>What are these messages about <quote>icmp-response
	bandwidth limit 300/200 pps</quote> in my log
	files?</para>
	</question>

	<answer>
	<para>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:</para>

	<itemizedlist>
	<listitem>
	<para>Brute-force denial of service (DoS) attacks (as
	opposed to single-packet attacks which exploit a
	specific vulnerability).</para>
	</listitem>

	<listitem>
	<para>Port scans which attempt to connect to a large
	number of ports (as opposed to only trying a few
	well-known ports).</para>
	</listitem>
	</itemizedlist>

	<para>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
	<varname>net.inet.icmp.icmplim</varname> sysctl variable
	like this, where <literal>300</literal> is the limit in
	packets per second:</para>

	<screen>&prompt.root; <userinput>sysctl -w net.inet.icmp.icmplim=300</userinput></screen>

	<para>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
	<varname>net.inet.icmp.icmplim_output</varname> sysctl
	variable to disable the output like this:</para>

	<screen>&prompt.root; <userinput>sysctl -w net.inet.icmp.icmplim_output=0</userinput></screen>

	<para>Finally, if you want to disable response limiting, you
	can set the <varname>net.inet.icmp.icmplim</varname>
	sysctl variable (see above for an example) to
	<literal>0</literal>. Disabling response limiting is
	discouraged for the reasons listed above.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="unknown-hw-addr-format">
	<para>What are these <errorname>arp: unknown hardware
	address format</errorname> error messages?</para>
	</question>

	<answer>
	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="cvsup-missing-libs">
	<para>I have just installed CVSup but trying to execute it
	produces errors. What is wrong?</para>
	</question>

	<answer>
	<para>First, see if the error message you are receiving is
	like the one shown below.</para>

	<programlisting>/usr/libexec/ld-elf.so.1: Shared object "libXaw.so.6" not found</programlisting>

	<para>Errors like these are caused by installing the
	<filename role="package">net/cvsup</filename> port on a
	machine which does not have the
	<application>&xfree86;</application> suite. If you want to
	use the <acronym>GUI</acronym> included with
	<application>CVSup</application> you will need to install
	<application>&xfree86;</application> now. Alternatively if
	you just wish to use <application>CVSup</application> from
	a command line you should delete the package previously
	installed. Then install the <filename
	role="package">net/cvsup-without-gui</filename> port. This
	is covered in more detail in the <ulink
	url="http://www.FreeBSD.org/doc/en_US.ISO8859-1/books/handbook/cvsup.html">CVSup
	section</ulink> of the Handbook.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="security">
	<title>Security</title>
	<qandaset>
	<qandaentry>
	<question id="sandbox">
	<para>What is a sandbox?</para>
	</question><answer>

	<para><quote>Sandbox</quote> is a security term. It can
	mean two things:</para>

	<itemizedlist>
	<listitem>

	<para>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.</para>

	<para>The process is said to be able to
	<quote>play</quote> 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.</para>

	<para>The walls might be a userid, for example. This is
	the definition used in the &man.security.7; and &man.named.8; man
	pages.</para>

	<para>Take the <literal>ntalk</literal> service, for
	example (see /etc/inetd.conf). This service used to run
	as userid <username>root</username>. Now it runs as userid
	<username>tty</username>. The <username>tty</username> 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.</para>
	</listitem>

	<listitem>

	<para>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.</para>

	<para>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.
	<filename>/</filename> for that process is this
	directory, not the real <filename>/</filename> of the
	system).</para>

	<para>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.</para>

	<para>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.</para>
	</listitem>
	</itemizedlist>

	<para>&unix; implements two core sandboxes. One is at the
	process level, and one is at the userid level.</para>

	<para>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.</para>

	<para>A &unix; process is owned by a particular userid. If
	the userid is not the <username>root</username> 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="securelevel">
	<para>What is securelevel?</para>
	</question>

	<answer>
	<para>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.,
	<username>root</username>) is allowed to do them. At the time
	of this writing, the securelevel mechanism is capable of, among
	other things, limiting the ability to,</para>

	<itemizedlist>
	<listitem>
	<para>unset certain file flags, such as
	<literal>schg</literal> (the system immutable flag),</para>
	</listitem>

	<listitem>
	<para>write to kernel memory via
	<devicename>/dev/mem</devicename> and
	<devicename>/dev/kmem</devicename>,</para>
	</listitem>

	<listitem>
	<para>load kernel modules, and</para>
	</listitem>

	<listitem>
	<para>alter firewall rules.</para>
	</listitem>
	</itemizedlist>

	<para>To check the status of the securelevel on a running system,
	simply execute the following command:</para>

	<screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>

	<para>The output will contain the name of the &man.sysctl.8;
	variable (in this case, <varname>kern.securelevel</varname>)
	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.</para>

	<para>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 <maketarget>installworld</maketarget> or changing the date),
	you will have to change the securelevel setting in
	<filename>/etc/rc.conf</filename> (you want to look for the
	<varname>kern_securelevel</varname> and
	<varname>kern_securelevel_enable</varname> variables) and
	reboot.</para>

	<para>For more information on securelevel and the specific things
	all the levels do, please consult the &man.init.8; manual
	page.</para>

	<warning>
	<para>Securelevel is not a silver bullet; it has many known
	deficiencies. More often than not, it provides a false
	sense of security.</para>

	<para>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.</para>

	<para>This point and others are often discussed on the
	mailing lists, particularly the &a.security;. Please search
	the archives <ulink
	url="&url.base;/search/index.html">here</ulink> 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.</para>

	<para>Consider yourself warned.</para>
	</warning>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="extra-named-port">
	<para>BIND (<command>named</command>) is listening on port 53 and
	some other high-numbered port. What is going on?</para>
	</question>

	<answer>
	<para>BIND 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
	<filename>/etc/namedb/named.conf</filename>:</para>

	<programlisting>options {
	query-source address * port 53;
	};</programlisting>

	<para>You can replace the <literal>*</literal> with a single IP
	address if you want to tighten things further.</para>

	<para>Congratulations, by the way. It is good practice to read
	your &man.sockstat.1; output and notice odd
	things!</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="sendmail-port-587">
	<para>Sendmail is listening on port 587 as well as the
	standard port 25! What is going on?</para>
	</question>

	<answer>
	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="toor-account">
	<para>What is this UID 0 <username>toor</username> account? Have I
	been compromised?</para>
	</question>

	<answer>
	<para>Do not worry. <username>toor</username> is an
	<quote>alternative</quote> 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 <username>root</username>'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 to be installed in
	<filename>/usr/local/bin</filename> which, by default, resides
	on a different filesystem. If <username>root</username>'s shell
	is located in <filename>/usr/local/bin</filename> and
	<filename>/usr</filename> (or whatever filesystem contains
	<filename>/usr/local/bin</filename>) is not mounted for some
	reason, <username>root</username> 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).</para>

	<para>Some people use <username>toor</username> for
	day-to-day <username>root</username> tasks with a
	non-standard shell, leaving <username>root</username>,
	with a standard shell, for single user mode or
	emergencies. By default you cannot log in using
	<username>toor</username> as it does not have a password,
	so log in as <username>root</username> and set a password
	for <username>toor</username> if you want to use
	it.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="suidperl">
	<para>Why is <command>suidperl</command> not working
	properly?</para>
	</question>

	<answer>
	<para>For security reasons, <command>suidperl</command> is
	installed without the suid bit by default. The system
	administrator can enable suid behavior with the following
	command.</para>

	<screen>&prompt.root; <userinput>chmod u+s /usr/bin/suidperl</userinput></screen>

	<para>If you want <command>suidperl</command> to be built
	suid during upgrades from source, edit
	<filename>/etc/make.conf</filename> and add
	<varname>ENABLE_SUIDPERL=true</varname> before you build
	<command>perl</command>.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="ppp">
	<title>PPP</title>

	<qandaset>
	<qandaentry>
	<question id="userppp">
	<para>I cannot make &man.ppp.8; work. What am I doing wrong?</para>
	</question>

	<answer>
	<para>You should first read the &man.ppp.8; manual page and
	the <ulink url="&url.books.handbook;/ppp-and-slip.html#USERPPP">
	PPP section of the handbook</ulink>. Enable logging with
	the command</para>

	<programlisting>set log Phase Chat Connect Carrier lcp ipcp ccp command</programlisting>

	<para>This command may be typed at the &man.ppp.8; command
	prompt or it may be entered in the
	<filename>/etc/ppp/ppp.conf</filename> configuration file
	(the start of the <literal>default</literal> section is
	the best place to put it). Make sure that
	<filename>/etc/syslog.conf</filename> (see
	&man.syslog.conf.5;) contains the lines</para>

	<programlisting>!ppp
	. /var/log/ppp.log</programlisting>

	<para>and that the file <filename>/var/log/ppp.log</filename>
	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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-hangs">
	<para>Why does &man.ppp.8; hang when I run it?</para>
	</question>

	<answer>
	<para>This is usually because your hostname will not resolve.
	The best way to fix this is to make sure that
	<filename>/etc/hosts</filename> is consulted by your
	resolver first by editing <filename>/etc/host.conf</filename>
	and putting the <literal>hosts</literal> line first. Then,
	simply put an entry in <filename>/etc/hosts</filename> for
	your local machine. If you have no local network, change your
	<hostid>localhost</hostid> line:</para>

	<programlisting>127.0.0.1 foo.example.com foo localhost</programlisting>

	<para>Otherwise, simply add another entry for your host.
	Consult the relevant manual pages for more details.</para>

	<para>You should be able to successfully <command>ping -c1
	`hostname`</command> when you are done.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-nodial-auto">
	<para>Why will &man.ppp.8; not dial in <literal>-auto</literal>
	mode?</para>
	</question>

	<answer>
	<para>First, check that you have got a default route. By
	running <command>netstat -rn</command> (see
	&man.netstat.1;), you should see two entries like
	this:</para>

	<programlisting>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</programlisting>

	<para>This is assuming that you have used the addresses from the
	handbook, the manual 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 <literal>HISADDR</literal>
	in the ppp.conf file.</para>

	<para>Another reason for the default route line being
	missing is that you have mistakenly set up a default
	router in your <filename>/etc/rc.conf</filename> (see
	&man.rc.conf.5;) file
	and you have omitted the line saying</para>

	<programlisting>delete ALL</programlisting>

	<para>from <filename>ppp.conf</filename>. If this is the
	case, go back to the <ulink
	url="&url.books.handbook;/ppp-and-slip.html#USERPPP-FINAL"> Final
	system configuration</ulink> section of the
	handbook.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="no-route-to-host">
	<para>What does <errorname>No route to host</errorname> mean?</para>
	</question>

	<answer>
	<para>This error is usually due to a missing</para>

	<programlisting>MYADDR:
	delete ALL
	add 0 0 HISADDR</programlisting>

	<para>section in your <filename>/etc/ppp/ppp.linkup</filename>
	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
	<literal>packet mode</literal> (packet mode is
	indicated by the capitalized <acronym>PPP</acronym> in the
	prompt):</para>

	<programlisting>delete ALL
	add 0 0 HISADDR</programlisting>

	<para>Refer to the <ulink
	url="&url.books.handbook;/ppp-and-slip.html#USERPPP-DYNAMICIP">
	PPP and Dynamic IP addresses</ulink> section of the handbook
	for further details.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="connection-threeminutedrop">
	<para>Why does my connection drop after about 3 minutes?</para>
	</question>

	<answer>
	<para>The default PPP timeout is 3 minutes. This can be
	adjusted with the line</para>

	<programlisting>set timeout <replaceable>NNN</replaceable></programlisting>

	<para>where <replaceable>NNN</replaceable> is the number of
	seconds of inactivity before the connection is closed. If
	<replaceable>NNN</replaceable> is zero, the connection is never
	closed due to a timeout. It is possible to put this command in
	the <filename>ppp.conf</filename> 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
	<application>ppp</application>'s server socket using
	&man.telnet.1; or &man.pppctl.8;.
	Refer to the
	&man.ppp.8; man
	page for further details.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-drop-heavy-load">
	<para>Why does my connection drop under heavy load?</para>
	</question>

	<answer>
	<para>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</para>

	<programlisting>disable lqr</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-drop-random">
	<para>Why does my connection drop after a random amount of
	time?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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:</para>

	<programlisting>set dial "...... ATS10=10 OK ......"</programlisting>

	<para>Refer to your modem manual for details.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-hangs-random">
	<para>Why does my connection hang after a random amount of
	time?</para>
	</question><answer>

	<para>Many people experience hung connections with no apparent
	explanation. The first thing to establish is which side of
	the link is hung.</para>

	<para>If you are using an external modem, you can simply try
	using &man.ping.8; to see if the <acronym>TD</acronym>
	light is flashing when you transmit data. If it flashes
	(and the <acronym>RD</acronym> light does not), the
	problem is with the remote end. If <acronym>TD</acronym>
	does not flash, the problem is local. With an internal
	modem, you will need to use the <literal>set
	server</literal> command in your
	<filename>ppp.conf</filename> 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 <literal>set socket</literal>
	command succeeded at startup time), the problem is
	local. If you can connect and things are still hung,
	enable local async logging with <literal>set log local
	async</literal> 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.</para>

	<para>Having established whether the problem is local or remote,
	you now have two possibilities:</para>

	<itemizedlist>
	<listitem>
	<para>If the problem is remote, read on entry <xref
	linkend="ppp-remote-not-responding">.</para>
	</listitem>

	<listitem>
	<para>If the problem is local, read on entry <xref
	linkend="ppp-hung">.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-remote-not-responding">
	<para>The remote end is not responding. What can I do?</para>
	</question>

	<answer>
	<para>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 <literal>enable lqr</literal> in your
	<filename>ppp.conf</filename> 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...</para>

	<para>First, try disabling all local compression by adding the
	following to your configuration:</para>

	<programlisting>disable pred1 deflate deflate24 protocomp acfcomp shortseq vj
	deny pred1 deflate deflate24 protocomp acfcomp shortseq vj</programlisting>

	<para>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).</para>

	<para>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 (<quote>Memory
	fault, core dumped</quote>?).</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-hung">
	<para>&man.ppp.8; has hung. What can I do?</para>
	</question>

	<answer>
	<para>Your best bet here is to rebuild &man.ppp.8; by adding
	<literal>CFLAGS+=-g</literal> and
	<literal>STRIP=</literal> to the end of the Makefile, then
	doing a <command>make clean && make &&
	make install</command>. When &man.ppp.8; hangs, find the
	&man.ppp.8; process id with <command>ps ajxww \| fgrep
	ppp</command> and run <command>gdb ppp
	<replaceable>PID</replaceable></command>. From the gdb
	prompt, you can then use <command>bt</command> to get a
	stack trace.</para>

	<para>Send the results to &a.brian;.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-loginok-thennothing">
	<para>Why does nothing happen after the <quote>Login OK!</quote>
	message?</para>
	</question>

	<answer>
	<para>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:</para>

	<programlisting>set openmode active</programlisting>

	<note>
	<para>It usually does no harm if both sides initiate
	negotiation, so openmode is now active by default.
	However, the next section explains when it
	<emphasis>does</emphasis> do some harm.</para>
	</note>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-same-magic">
	<para>I keep seeing errors about magic being the same. What does
	it mean?</para>
	</question>

	<answer>
	<para>Occasionally, just after connecting, you may see messages
	in the log that say <quote>magic is the same</quote>.
	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.</para>

	<para>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 <quote>reflect</quote> back.</para>

	<para>One part of the LCP negotiation is to establish a
	magic number for each side of the link so that
	<quote>reflections</quote> 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.</para>

	<para>This can be avoided by allowing the peer to start
	negotiating with the following line in your ppp.conf
	file:</para>

	<programlisting>set openmode passive</programlisting>

	<para>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:</para>

	<programlisting>set openmode active 3</programlisting>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-lcp-constant">
	<para>LCP negotiations continue until the connection is
	closed. What is wrong?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>Consider two implementations,
	<hostid>A</hostid> and
	<hostid>B</hostid>. <hostid>A</hostid> starts
	sending LCP requests immediately after connecting and
	<hostid>B</hostid> takes 7 seconds to start. When
	<hostid>B</hostid> starts, <hostid>A</hostid>
	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. <hostid>B</hostid> sends a
	REQ, then an ACK to the first of
	<hostid>A</hostid>'s REQs. This results in
	<hostid>A</hostid> entering the <acronym>OPENED</acronym>
	state and sending and ACK (the first) back to
	<hostid>B</hostid>. In the meantime,
	<hostid>B</hostid> sends back two more ACKs in response to
	the two additional REQs sent by <hostid>A</hostid>
	before <hostid>B</hostid> started up.
	<hostid>B</hostid> then receives the first ACK from
	<hostid>A</hostid> and enters the
	<acronym>OPENED</acronym> state.
	<hostid>A</hostid> receives the second ACK from
	<hostid>B</hostid> and goes back to the
	<acronym>REQ-SENT</acronym> state, sending another (forth) REQ
	as per the RFC. It then receives the third ACK and enters the
	<acronym>OPENED</acronym> state. In the meantime,
	<hostid>B</hostid> receives the forth REQ from
	<hostid>A</hostid>, resulting in it reverting to the
	<acronym>ACK-SENT</acronym> state and sending
	another (second) REQ and (forth) ACK as per the RFC.
	<hostid>A</hostid> gets the REQ, goes into
	<acronym>REQ-SENT</acronym> and sends another REQ. It
	immediately receives the following ACK and enters
	<acronym>OPENED</acronym>.</para>

	<para>This goes on until one side figures out that they are
	getting nowhere and gives up.</para>

	<para>The best way to avoid this is to configure one side to be
	<literal>passive</literal> - that is, make one side
	wait for the other to start negotiating. This can be done
	with the</para>

	<programlisting>set openmode passive</programlisting>

	<para>command. Care should be taken with this option. You
	should also use the</para>

	<programlisting>set stopped N</programlisting>

	<para>command to limit the amount of time that
	&man.ppp.8; waits for the peer to begin
	negotiations. Alternatively, the</para>

	<programlisting>set openmode active N</programlisting>

	<para>command (where <replaceable>N</replaceable> is the
	number of seconds to wait before starting negotiations) can be
	used. Check the manual page for details.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-shell-test-lockup">
	<para>Why does &man.ppp.8; lock up when I shell out to test
	it?</para>
	</question>

	<answer>
	<para>When you execute the <command>shell</command> or
	<command>!</command> 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.</para>

	<para>If you wish to execute commands like this, use the
	<command>!bg</command> command instead. This will execute
	the given command in the background, and &man.ppp.8; can
	continue to service the link.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-nullmodem">
	<para>Why does &man.ppp.8; over a null-modem cable never exit?</para>
	</question>

	<answer>
	<para>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</para>

	<programlisting>enable lqr</programlisting>

	<para>LQR is accepted by default if negotiated by the peer.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-auto-noreasondial">
	<para>Why does &man.ppp.8; dial for no reason in -auto mode?</para>
	</question><answer>

	<para>If &man.ppp.8; is dialing unexpectedly, you must
	determine the cause, and set up Dial filters (dfilters) to
	prevent such dialing.</para>

	<para>To determine the cause, use the following line:</para>

	<programlisting>set log +tcp/ip</programlisting>

	<para>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.</para>

	<para>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 <emphasis>not</emphasis> prevent &man.ppp.8;
	from passing the packets through an established
	connection), use the following:</para>

	<programlisting>set dfilter 1 deny udp src eq 53
	set dfilter 2 deny udp dst eq 53
	set dfilter 3 permit 0/0 0/0</programlisting>

	<para>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.</para>

	<para>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 <ulink
	url="&url.books.handbook;/smtp-dialup.html">using email with a
	dialup connection</ulink> in the FreeBSD Handbook 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 <filename>.mc</filename>
	file:</para>

	<programlisting>define(`confDELIVERY_MODE', `d')dnl</programlisting>

	<para>This will make sendmail queue everything until the
	queue is run (usually, sendmail is invoked with
	<option>-bd -q30m</option>, telling it to run the queue
	every 30 minutes) or until a <command>sendmail
	-q</command> is done (perhaps from your ppp.linkup
	file).</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ccp-errors">
	<para>What do these CCP errors mean?</para>
	</question>

	<answer>
	<para>I keep seeing the following errors in my log file:</para>

	<programlisting>CCP: CcpSendConfigReq
	CCP: Received Terminate Ack (1) state = Req-Sent (6)</programlisting>

	<para>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:</para>

	<programlisting>disable pred1</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-connectionspeed">
	<para>Why does &man.ppp.8; not log my connection speed?</para>
	</question>

	<answer>

	<para>In order to log all lines of your modem
	<quote>conversation</quote>, you must enable the
	following:</para>

	<programlisting>set log +connect</programlisting>

	<para>This will make &man.ppp.8; log
	everything up until the last requested <quote>expect</quote>
	string.</para>

	<para>If you wish to see your connect speed and are using PAP
	or CHAP (and therefore do not have anything to
	<quote>chat</quote> after the CONNECT in the dial script - no
	<literal>set login</literal> script), you must make sure that
	you instruct &man.ppp.8; to <quote>expect</quote> the whole CONNECT
	line, something like this:</para>

	<programlisting>set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 4 \
	\"\" ATZ OK-ATZ-OK ATDT\\T TIMEOUT 60 CONNECT \\c \\n"</programlisting>

	<para>Here, we get our CONNECT, send nothing, then expect a
	line-feed, forcing &man.ppp.8; to read
	the whole CONNECT response.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-ignores-backslash">
	<para>Why does &man.ppp.8; ignore the <literal>\</literal> character
	in my chat script?</para>
	</question><answer>

	<para>Ppp parses each line in your config files so that it can
	interpret strings such as
	<literal>set phone "123 456 789"</literal> correctly and
	realize that the number is actually only
	<emphasis>one</emphasis> argument. In order to specify a
	<literal>"</literal> character, you must escape it
	using a backslash (<literal>\</literal>).</para>

	<para>When the chat interpreter parses each argument, it
	re-interprets the argument in order to find any special
	escape sequences such as <literal>\P</literal> or
	<literal>\T</literal> (see the manual page). As a result of this
	double-parsing, you must remember to use the correct number of
	escapes.</para>

	<para>If you wish to actually send a <literal>\</literal>
	character to (say) your modem, you would need something
	like:</para>

	<programlisting>set dial "\"\" ATZ OK-ATZ-OK AT\\\\X OK"</programlisting>

	<para>resulting in the following sequence:</para>

	<programlisting>ATZ
	OK
	AT\X
	OK</programlisting>

	<para>or</para>

	<programlisting>set phone 1234567
	set dial "\"\" ATZ OK ATDT\\T"</programlisting>

	<para>resulting in the following sequence:</para>

	<programlisting>ATZ
	OK
	ATDT1234567</programlisting>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-segfault-nocore">
	<para>Why does &man.ppp.8; get a seg-fault, but I see no
	<filename>ppp.core</filename> file?</para>
	</question>

	<answer>
	<para>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,
	<emphasis>and</emphasis> you are sure you are using the
	latest version (see the start of this section), then you
	should do the following:</para>

	<screen>&prompt.user; <userinput>tar xfz ppp-*.src.tar.gz</userinput>
	&prompt.user; <userinput>cd ppp*/ppp</userinput>
	&prompt.user; <userinput>echo STRIP= >>Makefile</userinput>
	&prompt.user; <userinput>echo CFLAGS+=-g >>Makefile</userinput>
	&prompt.user; <userinput>make clean all</userinput>
	&prompt.user; <userinput>su</userinput>
	&prompt.root; <userinput>make install</userinput>
	&prompt.root; <userinput>chmod 555 /usr/sbin/ppp</userinput></screen>

	<para>You will now have a debuggable version of &man.ppp.8;
	installed. You will have to be <username>root</username>
	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.</para>

	<para>Now, if and when &man.ppp.8; receives the segmentation
	violation, it will dump a core file called
	<filename>ppp.core</filename>. You should then do the
	following:</para>

	<screen>&prompt.user; <userinput>su</userinput>
	&prompt.root; <userinput>gdb /usr/sbin/ppp ppp.core</userinput>
	<prompt>(gdb)</prompt> <userinput>bt</userinput>
	.....
	<prompt>(gdb)</prompt> <userinput>f 0</userinput>
	....
	<prompt>(gdb)</prompt> <userinput>i args</userinput>
	....
	<prompt>(gdb)</prompt> <userinput>l</userinput>
	.....</screen>

	<para>All of this information should be given alongside your
	question, making it possible to diagnose the problem.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-autodialprocess-noconnect">
	<para>Why does the process that forces a dial in auto mode never
	connect?</para>
	</question>

	<answer>
	<para>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 manual page for
	<literal>iface</literal>.</para>

	<para>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.</para>

	<para>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 <literal>:-)</literal>
	The current version of &man.ppp.8; does
	this, but most other implementations do not.</para>

	<para>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
	<literal>iface-alias</literal> option in the latest
	version of &man.ppp.8; is doing (with the help of
	&man.libalias.3; and &man.ppp.8;'s <option>-nat</option>
	switch) - it is maintaining all previous interface
	addresses and NATing them to the last negotiated
	address.</para>

	<para>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.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ppp-nat-games">
	<para>Why do most games not work with the -nat switch?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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 (<literal>set log +tcp/ip</literal>)
	on the gateway.</para>

	<para>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 <filename>/etc/ppp/ppp.conf</filename> will make the
	software functional:</para>

	<programlisting>nat port <replaceable>proto</replaceable> <replaceable>internalmachine</replaceable>:<replaceable>port</replaceable> <replaceable>port</replaceable></programlisting>

	<para>where <replaceable>proto</replaceable> is either
	<literal>tcp</literal> or <literal>udp</literal>,
	<replaceable>internalmachine</replaceable> is the machine that
	you want the packets to be sent to and
	<replaceable>port</replaceable> is the destination port number
	of the packets.</para>

	<para>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.</para>

	<para>If the port numbers are not consistent, there are three
	more options:</para>

	<orderedlist>
	<listitem>
	<para>Submit support in libalias. Examples of
	<quote>special cases</quote> can be found in
	<filename>/usr/src/lib/libalias/alias_*.c</filename>
	(<filename>alias_ftp.c</filename> 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
	<quote>route</quote> in the alias table so that the
	subsequent packets know where to go.</para>

	<para>This is the most difficult solution, but it is the
	best and will make the software work with multiple
	machines.</para>
	</listitem>

	<listitem>
	<para>Use a proxy. The application may support socks5
	for example, or (as in the <quote>cvsup</quote> case)
	may have a <quote>passive</quote> option that avoids
	ever requesting that the peer open connections back to
	the local machine.</para>
	</listitem>

	<listitem>
	<para>Redirect everything to the internal machine using
	<literal>nat addr</literal>. This is the
	sledge-hammer approach.</para>
	</listitem>
	</orderedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="useful-port-numbers">
	<para>Has anybody made a list of useful port numbers?</para>
	</question><answer>

	<para>Not yet, but this is intended to grow into such a list
	(if any interest is shown). In each example,
	<replaceable>internal</replaceable> should be replaced with
	the IP number of the machine playing the game.</para>

	<itemizedlist>
	<listitem>
	<para><application>Asheron's Call</application></para>

	<para><literal>nat port udp
	<replaceable>internal</replaceable>
	:65000 65000</literal></para>

	<para>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 <literal>nat port</literal>
	line for each one.</para>
	</listitem>

	<listitem>
	<para><application>Half Life</application></para>

	<para><literal>nat port udp
	<replaceable>internal</replaceable>:27005
	27015</literal></para>
	</listitem>

	<listitem>
	<para><application>PCAnywhere 8.0</application></para>

	<para><literal>nat port udp
	<replaceable>internal</replaceable>:5632
	5632</literal></para>

	<para><literal>nat port tcp
	<replaceable>internal</replaceable>:5631
	5631</literal></para>
	</listitem>

	<listitem>
	<para><application>Quake</application></para>

	<para><literal>nat port udp
	<replaceable>internal</replaceable>:6112
	6112</literal></para>
	</listitem>

	<listitem>
	<para><application>Quake 2</application></para>

	<para><literal>nat port udp
	<replaceable>internal</replaceable>:27901
	27910</literal></para>
	<para><literal>nat port udp
	<replaceable>internal</replaceable>:60021
	60021</literal></para>
	<para><literal>nat port udp
	<replaceable>internal</replaceable>:60040
	60040</literal></para>
	</listitem>

	<listitem>
	<para><application>Red Alert</application></para>

	<para><literal>nat port udp
	<replaceable>internal</replaceable>:8675
	8675</literal></para>

	<para><literal>nat port udp
	<replaceable>internal</replaceable>:5009
	5009</literal></para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="fcs-errors">
	<para>What are FCS errors?</para>
	</question>

	<answer>
	<para>FCS stands for <literal>F</literal>rame
	<literal>C</literal>heck <literal>S</literal>equence.
	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 <literal>show hdlc</literal>
	command.</para>

	<para>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.</para>

	<para>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
	<emphasis>must</emphasis> use software flow control, use the
	command <literal>set accmap 0x000a0000</literal> to tell
	&man.ppp.8; to escape the <literal>^Q</literal> and
	<literal>^S</literal> characters.</para>

	<para>Another reason for seeing too many FCS errors may be
	that the remote end has stopped talking
	<acronym>PPP</acronym>. You may want to enable
	<literal>async</literal> 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 <literal>close
	lcp</literal> command (a following <literal>term</literal>
	command will reconnect you to the shell on the remote
	machine.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry id=PPPoEwithNAT>
	<question id="macos-win98-pppoe-freeze">
	<para>Why do &macos; and &windows; 98 connections freeze when
	running PPPoE on the gateway?</para>
	</question>

	<answer>
	<para>Thanks to Michael Wozniak
	<email>mwozniak@netcom.ca</email> for figuring this out and
	Dan Flemming <email>danflemming@mac.com</email> for the Mac
	solution:</para>

	<para>This is due to what is called a <quote>Black Hole</quote>
	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)
	<emphasis>and</emphasis> have the <quote>do not
	fragment</quote> bit set (default of TCP) and the Telco router
	is not sending ICMP <quote>must fragment</quote> 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...)</para>

	<para>One fix is to use regedit on your 95/98 boxes to add the
	following registry entry...</para>

	<programlisting>HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\NetTrans\0000\MaxMTU</programlisting>

	<para>It should be a string with a value
	<quote>1436</quote>, as some ADSL routers are reported to
	be unable to deal with packets larger than this. This
	registry key has been changed to
	<literal>Tcpip\Parameters\Interfaces\<replaceable>ID for
	adapter</replaceable>\MTU</literal> in &windows; 2000 and
	becomes a DWORD.</para>

	<para>Refer to the Microsoft Knowledge Base documents <ulink
	url="http://support.microsoft.com/support/kb/articles/Q158/4/74.asp">Q158474
	- Windows TCPIP Registry Entries</ulink> and <ulink
	url="http://support.microsoft.com/support/kb/articles/Q120/6/42.asp">Q120642
	- TCPIP & NBT Configuration Parameters for &windowsnt;
	</ulink> for more information on changing &windows; MTU to
	work with a NAT router.</para>

	<para>Another regedit possibility under &windows; 2000 is to
	set the
	<literal>Tcpip\Parameters\Interfaces\<replaceable>ID for
	adapter</replaceable>\EnablePMTUBHDetect</literal> DWORD
	to 1 as mentioned in the Microsoft document 120642
	mentioned above.</para>

	<para>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 <ulink
	url="http://www.softworks.com/">Sustainable Softworks</ulink>,
	that will allow users to customize TCP/IP settings. &macos; NAT
	users should select <literal>ip_interface_MTU</literal> from
	the drop-down menu, enter <literal>1450</literal> instead of
	<literal>1500</literal> in the box, click the box next to
	<literal>Save as Auto Configure</literal>, and click
	<literal>Make Active</literal>.</para>

	<para>The latest version of &man.ppp.8;
	(2.3 or greater) has an <command>enable tcpmssfixup</command>
	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 <application>tcpmssd</application>
	port.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="desperation">
	<para>None of this helps - I am desperate! What can I do?</para>
	</question>

	<answer>
	<para>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 <command>netstat -rn</command>
	command (before and after connecting) to the &a.questions; or
	the <ulink url="news:comp.unix.bsd.freebsd.misc">
	comp.unix.bsd.freebsd.misc</ulink> news group, and someone
	should point you in the right direction.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="serial">
	<title>Serial Communications</title>

	<para>This section answers common questions about serial
	communications with FreeBSD. PPP and SLIP are covered in the
	<link linkend="networking">Networking</link> section.</para>


	<qandaset>
	<qandaentry>
	<question id="found-serial">
	<para>How do I tell if FreeBSD found my serial ports?</para>
	</question>

	<answer>
	<para>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</para>

	<screen>&prompt.user; <userinput>dmesg \| grep sio</userinput></screen>

	<para>after your system is up and running.</para>

	<para>Here is some example output from the above command:</para>

	<programlisting>sio0 at 0x3f8-0x3ff irq 4 on isa
	sio0: type 16550A
	sio1 at 0x2f8-0x2ff irq 3 on isa
	sio1: type 16550A</programlisting>

	<para>This shows two serial ports. The first is on irq 4, is
	using port address <literal>0x3f8</literal>, 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 <literal>0x2f8</literal>.
	Internal modem cards are treated just like serial ports — except
	that they always have a modem <quote>attached</quote> to the
	port.</para>

	<para>The <filename>GENERIC</filename> 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
	<link linkend="make-kernel">about building a kernel</link> for
	more details.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="found-modem">
	<para>How do I tell if FreeBSD found my modem cards?</para>
	</question>

	<answer>
	<para>Refer to the answer to the previous question.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="access-serial-ports">
	<para>How do I access the serial ports on FreeBSD?</para>
	</question>

	<answer>
	<para>The third serial port, <devicename>sio2</devicename>
	(see &man.sio.4;, known as <devicename>COM3</devicename> in DOS), is on
	<devicename>/dev/cuaa2</devicename> for dial-out devices,
	and on <devicename>/dev/ttyd2</devicename> for dial-in
	devices. What is the difference between these two classes
	of devices?</para>

	<para>You use
	<devicename>ttyd<replaceable>X</replaceable></devicename>
	for dial-ins. When opening
	<devicename>/dev/ttyd<replaceable>X</replaceable></devicename>
	in blocking mode, a process will wait for the
	corresponding
	<devicename>cuaa<replaceable>X</replaceable></devicename>
	device to become inactive, and then wait for the carrier
	detect line to go active. When you open the
	<devicename>cuaa<replaceable>X</replaceable></devicename>
	device, it makes sure the serial port is not already in
	use by the
	<devicename>ttyd<replaceable>X</replaceable></devicename>
	device. If the port is available, it <quote>steals</quote>
	it from the
	<devicename>ttyd<replaceable>X</replaceable></devicename>
	device. Also, the
	<devicename>cuaa<replaceable>X</replaceable></devicename>
	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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="enable-multiport-serial">
	<para>How do I enable support for a multiport serial
	card?</para>
	</question>

	<answer>
	<para>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
	<literal>COM_MULTIPORT</literal> option.</para>

	<para>The following example is for an AST 4-port serial card on
	irq 7:</para>

	<programlisting>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</programlisting>

	<para>The flags indicate that the master port has minor number 7
	(<literal>0x700</literal>), diagnostics enabled during probe
	(<literal>0x080</literal>), and all the ports share an irq
	(<literal>0x001</literal>).</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="multiport-serial-share-irq">
	<para>Can FreeBSD handle multiport serial cards sharing
	irqs?</para>
	</question>

	<answer>
	<para>Not yet. You will have to use a different irq for each
	card.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="default-serial-params">
	<para>Can I set the default serial parameters for a
	port?</para>
	</question>

	<answer>
	<para>The
	<devicename>ttyd<replaceable>X</replaceable></devicename>
	(or
	<devicename>cuaa<replaceable>X</replaceable></devicename>)
	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</para>

	<screen>&prompt.root; <userinput>stty -a -f /dev/ttyd1</userinput></screen>

	<para>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
	<quote>initial state</quote> device. For example, to turn on
	<acronym>CLOCAL</acronym> mode, 8 bits, and
	<acronym>XON/XOFF</acronym> flow control by default for
	ttyd5, do:</para>

	<screen>&prompt.root; <userinput>stty -f /dev/ttyid5 clocal cs8 ixon ixoff</userinput></screen>

	<para>A good place to do this is in
	<filename>/etc/rc.serial</filename>. Now, an application
	will have these settings by default when it opens
	<filename>ttyd5</filename>. It can still change these
	settings to its liking, though.</para>

	<para>You can also prevent certain settings from being
	changed by an application by making adjustments to the
	<quote>lock state</quote> device. For example, to lock
	the speed of <devicename>ttyd5</devicename> to 57600 bps,
	do</para>

	<screen>&prompt.root; <userinput>stty -f /dev/ttyld5 57600</userinput></screen>

	<para>Now, an application that opens
	<devicename>ttyd5</devicename> and tries to change the
	speed of the port will be stuck with 57600 bps.</para>

	<para>Naturally, you should make the initial state and lock
	state devices writable only by
	<username>root</username>. The &man.MAKEDEV.8; script does
	<emphasis>NOT</emphasis> do this when it creates the
	device entries.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="enable-dialup">
	<para>How can I enable dialup logins on my modem?</para>
	</question>

	<answer>
	<para>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
	(<acronym>DTR</acronym>) line goes from on to off. It should
	probably use <filename>RTS/CTS</filename> 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.</para>

	<para>For many Hayes command-set--compatible modems, this
	command will make these settings and store them in
	nonvolatile memory:</para>

	<programlisting>AT &C1 &D3 &K3 &Q6 S0=1 &W</programlisting>

	<para>See the section <link linkend="direct-at">on sending AT
	commands</link> below for information on how to make these
	settings without resorting to an &ms-dos; terminal program.</para>

	<para>Next, make an entry in <filename>/etc/ttys</filename>
	(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:</para>

	<programlisting>ttyd1 "/usr/libexec/getty std.57600" dialup on insecure</programlisting>

	<para>This line indicates that the second serial port
	(<devicename>/dev/ttyd1</devicename>) has a modem
	connected running at 57600 bps and no parity
	(<literal>std.57600</literal>, which comes from the file
	<filename>/etc/gettytab</filename>, see &man.gettytab.5;).
	The terminal type for this port is
	<literal>dialup</literal>. The port is
	<literal>on</literal> and is
	<literal>insecure</literal> — meaning
	<username>root</username> logins on the port are not
	allowed. For dialin ports like this one, use the
	<devicename>ttyd<replaceable>X</replaceable></devicename>
	entry.</para>

	<para>It is common practice to use <literal>dialup</literal>
	as the terminal type. Many users set up in their
	<filename>.profile</filename> or
	<filename>.login</filename> files a prompt for the actual
	terminal type if the starting type is dialup. The example
	shows the port as insecure. To become
	<username>root</username> on this port, you have to login
	as a regular user, then &man.su.1; to become
	<username>root</username>. If you use
	<literal>secure</literal> then <username>root</username>
	can login in directly.</para>

	<para>After making modifications to
	<filename>/etc/ttys</filename>, you need to send a hangup
	or <acronym>HUP</acronym> signal to the &man.init.8;
	process:</para>

	<screen>&prompt.root; <userinput>kill -HUP 1</userinput></screen>

	<para>This forces the &man.init.8; process to reread
	<filename>/etc/ttys</filename>. The init process will
	then start getty processes on all <literal>on</literal>
	ports. You can find out if logins are available for your
	port by typing</para>

	<screen>&prompt.user; <userinput>ps -ax \| grep '[t]tyd1'</userinput></screen>

	<para>You should see something like:</para>

	<programlisting>747 ?? I 0:00.04 /usr/libexec/getty std.57600 ttyd1</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="dumb-terminal">
	<para>How can I connect a dumb terminal to my FreeBSD
	box?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>Then, modify <filename>/etc/ttys</filename> (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:</para>

	<programlisting>ttyd4 "/usr/libexec/getty std.38400" wyse50 on secure</programlisting>

	<para>This example shows that the port on
	<devicename>/dev/ttyd4</devicename> has a wyse50 terminal
	connected at 38400 bps with no parity
	(<literal>std.38400</literal> from
	<filename>/etc/gettytab</filename>, see &man.gettytab.5;)
	and <username>root</username> logins are allowed
	(<literal>secure</literal>).</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="cannot-tip">
	<para>Why can I not run <command>tip</command> or
	<command>cu</command>?</para>
	</question>

	<answer>
	<para>On your system, the programs &man.tip.1; and
	&man.cu.1; are probably executable only by
	<username>uucp</username> and group
	<groupname>dialer</groupname>. You can use the group
	<groupname>dialer</groupname> to control who has access to
	your modem or remote systems. Just add yourself to group
	dialer.</para>

	<para>Alternatively, you can let everyone on your system run
	&man.tip.1; and &man.cu.1; by typing:</para>

	<screen>&prompt.root; <userinput>chmod 4511 /usr/bin/cu</userinput>
	&prompt.root; <userinput>chmod 4511 /usr/bin/tip</userinput></screen>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="hayes-unsupported">
	<para>My stock Hayes modem is not supported — what
	can I do?</para>
	</question>

	<answer>
	<para>Actually, the manual page for &man.tip.1; is out of
	date. There is a generic Hayes dialer already built in.
	Just use <literal>at=hayes</literal> in your
	<filename>/etc/remote</filename> (see &man.remote.5;)
	file.</para>

	<para>The Hayes driver is not smart enough to recognize some of
	the advanced features of newer modems — messages like
	<literal>BUSY</literal>, <literal>NO DIALTONE</literal>, or
	<literal>CONNECT 115200</literal> will just confuse it. You
	should turn those messages off when you use &man.tip.1;
	(using <literal>ATX0&W</literal>).</para>

	<para>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
	<literal>ATS7=45&W</literal>.</para>

	<para>Actually, as shipped &man.tip.1; does not yet
	support it fully. The solution is to edit the file
	<filename>tipconf.h</filename> in the directory
	<filename>/usr/src/usr.bin/tip/tip</filename>. Obviously you
	need the source distribution to do this.</para>

	<para>Edit the line <literal>#define HAYES 0</literal>
	to <literal>#define HAYES 1</literal>. Then
	<command>make</command> and <command>make install</command>.
	Everything works nicely after that.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="direct-at">
	<para>How am I expected to enter these AT commands?</para>
	</question>

	<answer>
	<para>Make what is called a <quote>direct</quote> entry in
	your <filename>/etc/remote</filename> file (see
	&man.remote.5;). For example, if your modem is hooked up
	to the first serial port,
	<devicename>/dev/cuaa0</devicename>, then put in the
	following line:</para>

	<programlisting>cuaa0:dv=/dev/cuaa0:br#19200:pa=none</programlisting>

	<para>Use the highest bps rate your modem supports in the br
	capability. Then, type <command>tip
	<devicename>cuaa0</devicename></command> (see &man.tip.1;)
	and you will be connected to your modem.</para>

	<para>If there is no <devicename>/dev/cuaa0</devicename> on your
	system, do this:</para>

	<screen>&prompt.root; <userinput>cd /dev</userinput>
	&prompt.root; <userinput>sh MAKEDEV cuaa0</userinput></screen>

	<para>Or use cu as <username>root</username> with the
	following command:</para>

	<screen>&prompt.root; <userinput>cu -l<replaceable>line</replaceable> -s<replaceable>speed</replaceable></userinput></screen>

	<para>with <replaceable>line</replaceable> being the serial
	port (e.g. <devicename>/dev/cuaa0</devicename>) and
	<replaceable>speed</replaceable> being the speed
	(e.g.<literal>57600</literal>). When you are done
	entering the AT commands hit <literal>~.</literal> to
	exit.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="gt-failure">
	<para>Why does the <literal><@></literal> sign for the pn
	capability not work?</para></question><answer>

	<para>The <literal><@></literal> sign in the phone
	number capability tells tip to look in
	<filename>/etc/phones</filename> for a phone number. But
	the <literal><@></literal> sign is also a special
	character in capability files like
	<filename>/etc/remote</filename>. Escape it with a
	backslash:</para>

	<programlisting>pn=\@</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="dial-command-line">
	<para>How can I dial a phone number on the command
	line?</para>
	</question><answer>

	<para>Put what is called a <quote>generic</quote> entry in
	your <filename>/etc/remote</filename> file (see
	&man.remote.5;). For example:</para>

	<programlisting>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:</programlisting>

	<para>Then you can do something like <command>tip -115200
	5551234</command>. If you prefer &man.cu.1; over
	&man.tip.1;, use a generic cu entry:</para>

	<programlisting>cu115200\|Use cu to dial any number at 115200bps:\
	:dv=/dev/cuaa1:br#57600:at=hayes:pa=none:du:</programlisting>

	<para>and type <command>cu 5551234 -s 115200</command>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="set-bps">
	<para>Do I have to type in the bps rate every time I do
	that?</para>
	</question><answer>

	<para>Put in an entry for <literal>tip1200</literal> or
	<literal>cu1200</literal>, 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 <literal>tip1200</literal> entry. You do
	not have to use 1200 bps, though.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="terminal-server">
	<para>How can I more easily access a number of hosts through a
	terminal server?</para>
	</question>

	<answer>
	<para>Rather than waiting until you are connected and typing
	<literal>CONNECT <replaceable>host</replaceable></literal>
	each time, use tip's <literal>cm</literal> capability. For
	example, these entries in
	<filename>/etc/remote</filename> (see &man.remote.5;):</para>

	<programlisting>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:</programlisting>

	<para>will let you type <command>tip pain</command> or
	<command>tip muffin</command> to connect to the hosts
	<hostid>pain</hostid> or <hostid>muffin</hostid>; and
	<command>tip deep13</command> to get to the terminal
	server.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="tip-multiline">
	<para>Can tip try more than one line for each site?</para>
	</question>

	<answer>
	<para>This is often a problem where a university has several
	modem lines and several thousand students trying to use
	them...</para>

	<para>Make an entry for your university in
	<filename>/etc/remote</filename> (see &man.remote.5;) and
	use <literal><\@></literal> for the
	<literal>pn</literal> capability:</para>

	<programlisting>big-university:\
	:pn=\@:tc=dialout
	dialout:\
	:dv=/dev/cuaa3:br#9600:at=courier:du:pa=none:</programlisting>

	<para>Then, list the phone numbers for the university in
	<filename>/etc/phones</filename> (see &man.phones.5;):</para>

	<programlisting>big-university 5551111
	big-university 5551112
	big-university 5551113
	big-university 5551114</programlisting>

	<para>&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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="multi-controlp">
	<para>Why do I have to hit <keycombo
	action="simul"><keycap>CTRL</keycap><keycap>P</keycap></keycombo>
	twice to send <keycombo
	action="simul"><keycap>CTRL</keycap><keycap>P</keycap></keycombo>
	once?</para>
	</question>

	<answer>
	<para><keycombo
	action="simul"><keycap>CTRL</keycap><keycap>P</keycap></keycombo>
	is the default <quote>force</quote> 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 <literal>~s</literal> escape, which means
	<quote>set a variable</quote>.</para>

	<para>Type <literal>~sforce=<replaceable>single-char
	</replaceable></literal> followed by a newline.
	<replaceable>single-char</replaceable> is any single
	character. If you leave out
	<replaceable>single-char</replaceable>, then the force
	character is the nul character, which you can get by
	typing <keycombo
	action="simul"><keycap>CTRL</keycap><keycap>2</keycap></keycombo>
	or <keycombo
	action="simul"><keycap>CTRL</keycap><keycap>SPACE</keycap></keycombo>.
	A pretty good value for
	<replaceable>single-char</replaceable> is <keycombo
	action="simul"><keycap>SHIFT</keycap><keycap>CTRL</keycap><keycap>6</keycap></keycombo>,
	which I have seen only used on some terminal
	servers.</para>

	<para>You can have the force character be whatever you want
	by specifying the following in your
	<filename>$HOME/.tiprc</filename> file:</para>

	<programlisting>force=<replaceable>single-char</replaceable></programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="uppercase">
	<para>Why is everything I type suddenly in UPPER CASE?</para>
	</question>

	<answer>
	<para>You must have pressed <keycombo
	action="simul"><keycap>CTRL</keycap><keycap>A</keycap></keycombo>,
	&man.tip.1; <quote>raise character</quote>, specially
	designed for people with broken <keycap>Caps Lock</keycap>
	keys. Use <literal>~s</literal> as above and set the
	variable <quote>raisechar</quote> 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.</para>

	<para>Here is a sample .tiprc file perfect for Emacs users
	who need to type <keycombo
	action="simul"><keycap>CTRL</keycap><keycap>2</keycap></keycombo>
	and <keycombo
	action="simul"><keycap>CTRL</keycap><keycap>A</keycap></keycombo>
	a lot:</para>

	<programlisting>force=^^
	raisechar=^^</programlisting>

	<para>The ^^ is <keycombo action="simul"><keycap>SHIFT</keycap><keycap>CTRL</keycap><keycap>6</keycap></keycombo>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="tip-filetransfer">
	<para>How can I do file transfers with
	<command>tip</command>?</para>
	</question>

	<answer>
	<para>If you are talking to another &unix; system, you can
	send and receive files with <literal>~p</literal> (put)
	and <literal>~t</literal> (take). These commands run
	&man.cat.1; and &man.echo.1; on the remote system to
	accept and send files. The syntax is:</para>

	<programlisting>~p <local-file> [<remote-file>]
	~t <remote-file> [<local-file>]</programlisting>

	<para>There is no error checking, so you probably should use
	another protocol, like zmodem.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="zmodem-tip">
	<para>How can I run zmodem with
	<application>tip</application>?</para>
	</question>

	<answer>
	<para>First, install one of the zmodem programs from the
	ports collection (such as one of the two from the comms
	category, <application>lrzsz</application> or
	<application>rzsz</application>.</para>

	<para>To receive files, start the sending program on the
	remote end. Then, press enter and type <literal>~C
	rz</literal> (or <literal>~C lrz</literal> if you
	installed <application>lrzsz</application>) to begin
	receiving them locally.</para>

	<para>To send files, start the receiving program on the
	remote end. Then, press enter and type <literal>~C sz
	<replaceable>files</replaceable></literal> (or <literal>~C
	lsz <replaceable>files</replaceable></literal>) to send
	them to the remote system.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="misc">
	<title>Miscellaneous Questions</title>

	<qandaset>
	<qandaentry>
	<question id="more-swap">
	<para>FreeBSD uses far more swap space than &linux;. Why?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="top-freemem">
	<para>Why does <command>top</command> show very little free
	memory even when I have very few programs running?</para>
	</question>

	<answer>
	<para>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
	<literal>Inact</literal>, <literal>Cache</literal>, and
	<literal>Buf</literal> 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 <literal>Free</literal>
	memory in &man.top.1; is good, provided it is not
	<emphasis>very</emphasis> low.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="chmod-symlinks">
	<para>Why will <command>chmod</command> not change the
	permissions on symlinks?</para>
	</question>

	<answer>
	<para>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,
	<filename>foo</filename>, and a symlink to that file,
	<filename>bar</filename>, then this command will always
	succeed.</para>

	<screen>&prompt.user; <userinput>chmod g-w bar</userinput></screen>

	<para>However, the permissions on <filename>foo</filename> will
	not have changed.</para>

	<para>You have to use either <option>-H</option> or
	<option>-L</option> together with the <option>-R</option>
	option to make this work. See the &man.chmod.1; and
	&man.symlink.7; manual pages for more info.</para>

	<warning>
	<para>The <option>-R</option> option does a
	<emphasis>RECURSIVE</emphasis> &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
	(<filename>/</filename>). For example, if
	<filename>foo</filename> is a symlink to directory
	<filename>bar</filename>, and you want to change the
	permissions of <filename>foo</filename> (actually
	<filename>bar</filename>), you would do something
	like:</para>

	<screen>&prompt.user; <userinput>chmod 555 foo/</userinput></screen>

	<para>With the trailing slash, &man.chmod.1; will follow
	the symlink, <filename>foo</filename>, to change the
	permissions of the directory,
	<filename>bar</filename>.</para>
	</warning>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="dos-binaries">
	<para>Can I run DOS binaries under FreeBSD?</para>
	</question>

	<answer>
	<para>Yes, you can use <filename
	role="package">emulators/doscmd</filename>, a DOS emulation
	program, available in the &os; Ports Collection.</para>

	<note>
	<para>The <application>doscmd</application> program used to be an
	integrated part of &os;, but was removed before the release of
	&os; 5.3.</para>
	</note>

	<para>If <application>doscmd</application> will not suffice,
	the add-on utility <filename
	role="package">emulators/pcemu</filename> emulates an 8088 and
	enough BIOS services to run many DOS text mode
	applications. It requires the X Window System.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="translation">
	<para>What do I need to do to translate a FreeBSD document into
	my native language?</para>
	</question>

	<answer>
	<para>See the <ulink url="&url.books.fdp-primer;/translations.html">
	Translation FAQ</ulink> in the FreeBSD Documentation Project
	Primer.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="freebsd-mail-bounces">
	<para>Why does my email to any address at FreeBSD.org bounce?</para>
	</question>

	<answer>
	<para>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:</para>

	<itemizedlist>
	<listitem>
	<para>The email is being sent from a known spam
	domain or IP block.</para>

	<para>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.</para>
	</listitem>

	<listitem>
	<para>The body of the email only contains HTML.</para>

	<para>Mail should be sent in plain text only. Please
	configure your mail user agent to send plain
	text.</para>
	</listitem>

	<listitem>
	<para>The mailer at FreeBSD.org cannot resolve the IP
	address of the connecting host back to a symbolic
	name.</para>

	<para>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.</para>
	</listitem>

	<listitem>
	<para>The hostname given in the EHLO/HELO part of the SMTP
	exchange cannot be resolved to an IP address.</para>

	<para>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.</para>
	</listitem>

	<listitem>
	<para>Your message had a message ID ending with the string
	<quote>localhost</quote>.</para>

	<para>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.</para>
	</listitem>
	</itemizedlist>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="free-account">
	<para>Where can I find a free FreeBSD account?</para>
	</question>

	<answer>
	<para>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.</para>

	<para><ulink url="http://www.arbornet.org/">Arbornet,
	Inc</ulink>, 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.</para>

	<para><ulink url="http://www.grex.org/">Grex</ulink> 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;.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="sup-define">
	<para>What is <command>sup</command>, and how do I use
	it?</para>
	</question>

	<answer>
	<para><ulink url="http://www.FreeBSD.org/cgi/ports.cgi?^sup">
	SUP</ulink> 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.</para>

	<para>SUP is not bandwidth friendly, and has been retired.
	The current recommended method to keep your sources up to
	date is <ulink url="&url.books.handbook;/synching.html#CVSUP">
	CVSup</ulink></para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="daemon-name">
	<para>What is the cute little red guy's name?</para>
	</question>

	<answer>
	<para>He does not have one, and is just called <quote>the BSD
	daemon</quote>. If you insist upon using a name, call him
	<quote>beastie</quote>. Note that <quote>beastie</quote>
	is pronounced <quote>BSD</quote>.</para>

	<para>You can learn more about the BSD daemon on his <ulink
	url="http://www.mckusick.com/beastie/index.html">home
	page</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="use-beastie">
	<para>Can I use the BSD daemon image?</para>
	</question>

	<answer>
	<para>Perhaps. The BSD daemon is copyrighted by Marshall
	Kirk McKusick. You will want to check his <ulink
	url="http://www.mckusick.com/beastie/mainpage/copyright.html">Statement
	on the Use of the BSD Daemon Figure</ulink> for detailed
	usage terms.</para>

	<para>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
	<ulink
	url="http://www.mckusick.com/beastie/index.html">BSD
	Daemon's home page</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="daemon-images">
	<para>Do you have any BSD daemon images I could use?</para>
	</question>

	<answer>
	<para>You will find eps and Xfig drawings under
	<filename>/usr/share/examples/BSD_daemon/</filename>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="glossary">
	<para>I have seen an acronym or other term on the mailing
	lists and I do not understand what it means. Where should
	I look?</para>
	</question>

	<answer>
	<para>Please see the <ulink
	url="&url.books.handbook;/freebsd-glossary.html">
	&os Glossary</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="bikeshed-painting">
	<para>Why should I care what color the bikeshed is?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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 <quote><ulink
	url="http://www.FreeBSD.org/cgi/getmsg.cgi?fetch=506636+517178+/usr/local/www/db/text/1999/freebsd-hackers/19991003.freebsd-hackers">A bike
	shed (any color will do) on greener grass...</ulink></quote>.
	The appropriate portions of that message are quoted
	below.</para>

	<blockquote>
	<attribution>&a.phk; on freebsd-hackers, October
	2, 1999</attribution>

	<para>
	<quote>What is it about this bike shed?</quote> Some
	of you have asked me.</para>

	<para>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 <quote>Parkinson's
	Law</quote>, which contains a lot of insight into the
	dynamics of management.</para>

	<para>[snip a bit of commentary on the book]</para>

	<para>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.</para>

	<para>Parkinson shows how you can go into 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.</para>

	<para>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.</para>

	<para>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
	<emphasis>here</emphasis>.</para>

	<para>In Denmark we call it <quote>setting your
	fingerprint</quote>. It is about personal pride and
	prestige, it is about being able to point somewhere and
	say <quote>There! <emphasis>I</emphasis> did that.</quote>
	It is a strong trait in politicians, but present in most
	people given the chance. Just think about footsteps in
	wet cement.</para>
	</blockquote>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="funnies">
	<title>The FreeBSD Funnies</title>

	<qandaset>
	<qandaentry>
	<question id="very-very-cool">
	<para>How cool is FreeBSD?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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 <quote>scratch and
	sniff</quote> GUI. It is a funny old business we are in!</para>

	<para>Seriously, both FreeBSD and &linux; use the
	<acronym>HLT</acronym> (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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="letmeoutofhere">
	<para>Who is scratching in my memory banks??</para>
	</question>

	<answer>
	<para>Q. Is there anything <quote>odd</quote> 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.</para>

	<para>A. Yes! You will see frequent references to
	<quote>daemons</quote> 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.</para>

	<para>If the noise gets to you, a good
	<command>fdisk /mbr</command> 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?</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="changing-lightbulbs">
	<para>How many FreeBSD hackers does it take to change a
	lightbulb?</para>
	</question>

	<answer>
	<para>One thousand, one hundred and sixty-nine:</para>

	<para>Twenty-three to complain to -CURRENT about the lights
	being out;</para>

	<para>Four to claim that it is a configuration problem, and
	that such matters really belong on -questions;</para>

	<para>Three to submit PRs about it, one of which is misfiled
	under doc and consists only of <quote>it's dark</quote>;</para>

	<para>One to commit an untested lightbulb which breaks
	buildworld, then back it out five minutes later;</para>

	<para>Eight to flame the PR originators for not including
	patches in their PRs;</para>

	<para>Five to complain about buildworld being broken;</para>

	<para>Thirty-one to answer that it works for them, and they
	must have cvsupped at a bad time;</para>

	<para>One to post a patch for a new lightbulb to -hackers;</para>

	<para>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;</para>

	<para>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!?</para>

	<para>Two hundred to complain about the color of the bicycle
	shed;</para>

	<para>Three to point out that the patch breaks &man.style.9;;</para>

	<para>Seventeen to complain that the proposed new lightbulb is
	under GPL;</para>

	<para>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;</para>

	<para>Seven to move various portions of the thread to -chat
	and -advocacy;</para>

	<para>One to commit the suggested lightbulb, even though it
	shines dimmer than the old one;</para>

	<para>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;</para>

	<para>Forty-six to argue vociferously about the backing out
	of the dim lightbulb and demanding a statement from
	-core;</para>

	<para>Eleven to request a smaller lightbulb so it will fit
	their Tamagotchi if we ever decide to port FreeBSD to that
	platform;</para>

	<para>Seventy-three to complain about the SNR on -hackers and
	-chat and unsubscribe in protest;</para>

	<para>Thirteen to post <quote>unsubscribe</quote>,
	<quote>How do I unsubscribe?</quote>, or <quote>Please
	remove me from the list</quote>, followed by the usual
	footer;</para>

	<para>One to commit a working lightbulb while everybody is too
	busy flaming everybody else to notice;</para>

	<para>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;</para>

	<para>One to complain that the new lightbulb lacks
	fairings;</para>

	<para>Nine (including the PR originators) to ask
	<quote>what is MFC?</quote>;</para>

	<para>Fifty-seven to complain about the lights being out two
	weeks after the bulb has been changed.</para>

	<para><emphasis>&a.nik; adds:</emphasis></para>

	<para><emphasis>I was laughing quite hard at
	this.</emphasis></para>

	<para><emphasis>And then I thought, <quote>Hang on,
	shouldn't there be '1 to document it.' in that list
	somewhere?</quote></emphasis></para>

	<para><emphasis>And then I was enlightened :-)</emphasis></para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="dev-null">
	<para>Where does data written to <filename>/dev/null</filename>
	go?</para>
	</question>
	<answer>
	<para>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 <filename>/dev/null</filename>, overheating
	their CPUs. If you delete <filename>/dev/null</filename>
	(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
	<filename>/dev/random</filename> and sending it off
	somewhere; however you run the risk of overheating your
	network connection and <filename>/</filename> 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.</para>

	<para><emphasis>Paul Robinson adds:</emphasis></para>

	<para>There are other methods. As every good sysadmin knows,
	it is part of standard practice 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 <quote>pixels</quote> are categorized by the type of hat
	they wear (red, green or blue) and will hide or appear
	(thereby showing the color 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 stimulation
	- this is why screen savers exist.</para>

	<para>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.</para>

	<para>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.</para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="advanced">
	<title>Advanced Topics</title>

	<qandaset>
	<qandaentry>
	<question id="learn-advanced">
	<para>How can I learn more about FreeBSD's internals?</para>
	</question>

	<answer>
	<para>At this time, there is only one book on FreeBSD-specific OS
	internals, namely <quote>The Design and Implementation of the
	FreeBSD Operating System</quote> by Marshall Kirk McKusick and
	George V. Neville-Neil, ISBN 0-201-70245-2, which
	focuses on version 5.X of FreeBSD.</para>

	<para>Additionally, much general &unix; knowledge is directly
	applicable to FreeBSD.</para>

	<para>For a list of relevant books, please check the Handbook's <ulink
	url="&url.books.handbook;/bibliography-osinternals.html">Operating
	System Internals Bibliography</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="how-to-contribute">
	<para>How can I contribute to FreeBSD?</para>
	</question>

	<answer>
	<para>Please see the article on <ulink
	url="&url.articles.contributing;/article.html">Contributing
	to FreeBSD</ulink> for specific advice on how to do this.
	Assistance is more than welcome!</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="define-snap-release">
	<para>What are SNAPs and RELEASEs?</para>
	</question>

	<answer>
	<para>There are currently three active/semi-active branches
	in the FreeBSD <ulink
	url="http://www.FreeBSD.org/cgi/cvsweb.cgi"> CVS
	Repository</ulink>. (Earlier branches are only changed
	very rarely, which is why there are only three active
	branches of development):</para>

	<itemizedlist>
	<listitem>
	<para><literal>RELENG_5</literal> AKA
	<emphasis>5-STABLE</emphasis></para>
	</listitem>

	<listitem>
	<para><literal>RELENG_6</literal> AKA
	<emphasis>6-STABLE</emphasis></para>
	</listitem>

	<listitem>
	<para><literal>HEAD</literal> AKA
	<emphasis>-CURRENT</emphasis> AKA
	<emphasis>7.X-CURRENT</emphasis></para>
	</listitem>

	</itemizedlist>

	<para><literal>HEAD</literal> is not an actual branch tag,
	like the other two; it is simply a symbolic constant for
	<quote><emphasis>the current, non-branched development
	stream</emphasis></quote> which we simply refer to as
	<quote>-CURRENT</quote>.</para>

	<para>Right now, <quote>-CURRENT</quote> is the 7.X development
	stream; the <literal>5-STABLE</literal> branch,
	<symbol>RELENG_5</symbol>, forked off from
	<quote>-CURRENT</quote> in October 2004, and
	the <literal>6-STABLE</literal> branch,
	<symbol>RELENG_6</symbol>, forked off from
	<quote>-CURRENT</quote> in November 2005.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="custrel">
	<para>How do I make my own custom release?</para>
	</question>

	<answer>
	<para>Please see the <ulink
	url="&url.articles.releng;/article.html">
	Release Engineering</ulink> article.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="makeworld-clobbers">
	<para>Why does <command>make world</command> clobber my existing
	installed binaries?</para>
	</question>

	<answer>
	<para>Yes, this is the general idea; as its name might suggest,
	<command>make world</command> 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).</para>

	<para>If the environment variable <literal>DESTDIR</literal>
	is defined while running <command>make world</command> or
	<command>make install</command>, the newly-created binaries
	will be deposited in a directory tree identical to the
	installed one, rooted at <literal>${DESTDIR}</literal>.
	Some random combination of shared libraries modifications and
	program rebuilds can cause this to fail in <command>make
	world</command> however.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="cvsup-round-robin">
	<para>Why isn't cvsup.FreeBSD.org a round robin DNS entry to
	share the load amongst the various CVSup servers?</para>
	</question>

	<answer>
	<para>While CVSup mirrors update from the master CVSup
	server hourly, this update might happen at any time during
	the hour. This means that some servers have newer code
	than others, even though all servers have code that is
	less than an hour old. If <hostid role="fqdn">cvsup.FreeBSD.org</hostid> was a round
	robin DNS entry that simply redirected users to a random
	CVSup server, running CVSup twice in a row could download
	code older than the code already on the system.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="bus-speed-defaulted">
	<para>Why does my system say <quote>(bus speed
	defaulted)</quote> when it boots?</para>
	</question>

	<answer>

	<para>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
	<symbol>TUNE_1542</symbol> 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.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="ctm">
	<para>Can I follow -CURRENT with limited Internet access?</para>
	</question>

	<answer>
	<para>Yes, you can do this <emphasis>without</emphasis>
	downloading the whole source tree by using the <ulink
	url="&url.books.handbook;/synching.html#CTM">CTM facility</ulink>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="split-240k">
	<para>How did you split the distribution into 240k files?</para>
	</question>

	<answer>
	<para>Newer BSD based systems have a <option>-b</option>
	option to &man.split.1; that allows them to split files on arbitrary
	byte boundaries.</para>

	<para>Here is an example from
	<filename>/usr/src/Makefile</filename>.</para>

	<programlisting>bin-tarball:
	(cd ${DISTDIR}; \
	tar cf - . \
	gzip --no-name -9 -c \| \
	split -b 240640 - \
	${RELEASEDIR}/tarballs/bindist/bin_tgz.)</programlisting>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="submitting-kernel-extensions">
	<para>I have written a kernel extension, who do I send it
	to?</para>
	</question>

	<answer>
	<para>Please take a look at the article on <ulink
	url="&url.articles.contributing;/article.html">Contributing
	to FreeBSD</ulink> to learn how to submit code.</para>

	<para>And thanks for the thought!</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="pnp-initialize">
	<para>How are Plug N Play ISA cards detected and
	initialized?</para>
	</question>

	<answer>
	<para>By: Frank Durda IV
	<email>uhclem@nemesis.lonestar.org</email></para>

	<para>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, it 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 <quote>yes</quote> 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 <quote>off-line</quote>. It
	then looks to see if any boards are still responding to the
	query. If the answer was <literal>0</literal>, then there are
	no boards with IDs above X. Now probe asks if there are any
	boards below <literal>X</literal>. 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.</para>

	<para>The IDs are two 32-bit fields (hence 2&circ;64) + 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.</para>

	<para>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.</para>

	<para>The 32 bit groups can never be all zero. This allows the
	wired-OR to show non-zero bits during the initial binary
	search.</para>

	<para>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.</para>

	<para>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.</para>

	<para>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.</para>

	<para>There is a lot of oversimplification above, but you
	should get the general idea.</para>

	<para>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
	<quote>tough</quote>. So they do a write to the printer status
	port for setting addresses, plus that use that address +
	<literal>0x800</literal>, and a third I/O port for reading that
	can be located anywhere between <literal>0x200</literal> and
	<literal>0x3ff</literal>.</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="major-numbers">
	<para>Can you assign a major number for a device driver I have
	written?</para>
	</question>

	<answer>

	<para>&os.current; after February 2003 has a facility for
	dynamically and automatically allocating major numbers for
	device drivers at runtime. This mechanism is highly
	preferred to the older procedure of statically allocating
	device numbers. Some comments on this subject can be
	found in <filename>src/sys/conf/majors</filename>.</para>

	<para>If you are forced for some reason to use a static
	major number, the procedure for obtaining one 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
	<filename>files.i386</filename>, 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 the &a.hackers;.</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question id="alternate-directory-layout">
	<para>What about alternative layout policies for
	directories?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>Kirk McKusick, September 1998</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="kernel-panic-troubleshooting">
	<para>How can I make the most of the data I see when my kernel
	panics?</para>
	</question>

	<answer>
	<para><emphasis>[This section was extracted from a mail
	written by &a.wpaul; on the freebsd-current
	<link linkend="mailing">mailing list</link> by &a.des;, who
	fixed a few typos and added the bracketed comments]
	</emphasis></para>

	<programlisting>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</programlisting>

	<para><emphasis>Ben Rosengart posted the following
	panic message]</emphasis></para>

	<programlisting>> 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</programlisting>

	<para>[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 <emphasis>you</emphasis> can tell us where the fault
	occurred.</para>

	<para>What you should do is this:</para>

	<procedure>
	<step>
	<para>Write down the instruction pointer value. Note that
	the <literal>0x8:</literal> part at the beginning is not
	significant in this case: it is the
	<literal>0xf0xxxxxx</literal> part that we want.</para>
	</step>

	<step>
	<para>When the system reboots, do the following:

	<screen>&prompt.user; <userinput>nm -n /kernel.that.caused.the.panic \| grep f0xxxxxx</userinput></screen>

	where <literal>f0xxxxxx</literal> 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.:

	<screen>&prompt.user; <userinput>nm -n /kernel.that.caused.the.panic \| grep f0xxxxx</userinput></screen>

	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.</para>
	</step>
	</procedure>

	<para>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.</para>

	<para>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.</para>

	<para>In any case, the method I normally use is this:</para>

	<procedure>
	<step>
	<para>Set up a kernel config file, optionally adding
	<literal>options DDB</literal> 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.)</para>
	</step>

	<step>
	<para>Use <command>config -g
	<replaceable>KERNELCONFIG</replaceable></command> to set
	up the build directory.</para>
	</step>

	<step>
	<para><command>cd /sys/compile/<replaceable>KERNELCONFIG</replaceable>; make</command></para>
	</step>

	<step>
	<para>Wait for kernel to finish compiling.</para>
	</step>

	<step>
	<para><command>make install</command></para>
	</step>

	<step>
	<para>reboot</para>
	</step>
	</procedure>

	<para>The &man.make.1; process will have built two kernels.
	<filename>kernel</filename> and
	<filename>kernel.debug</filename>.
	<filename>kernel</filename> was installed as
	<filename>/kernel</filename>, while
	<filename>kernel.debug</filename> can be used as the
	source of debugging symbols for &man.gdb.1;.</para>

	<para>To make sure you capture a crash dump, you need edit
	<filename>/etc/rc.conf</filename> and set
	<literal>dumpdev</literal> 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
	<literal>dumpdev</literal> is set in
	<filename>/etc/rc.conf</filename>, the &man.rc.8; scripts
	will run &man.savecore.8; automatically and put the crash
	dump in <filename>/var/crash</filename>.</para>

	<note>
	<para>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
	<filename>/var/crash</filename> 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 <literal>options
	MAXMEM=(foo)</literal> 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.</para>
	</note>

	<para>Once you have recovered the crash dump, you can get a
	stack trace with &man.gdb.1; as follows:</para>

	<screen>&prompt.user; <userinput>gdb -k /sys/compile/KERNELCONFIG/kernel.debug /var/crash/vmcore.0</userinput>
	<prompt>(gdb)</prompt> <userinput>where</userinput></screen>

	<para>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.</para>

	<para>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.</para>

	<para><emphasis>[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]</emphasis></para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="dlsym-failure">
	<para>Why has dlsym() stopped working for ELF executables?</para>
	</question>

	<answer>
	<para>The ELF toolchain does not, by default, make the symbols
	defined in an executable visible to the dynamic linker.
	Consequently <function>dlsym()</function> searches on handles
	obtained from calls to <function>dlopen(NULL,
	flags)</function> will fail to find such symbols.</para>

	<para>If you want to search, using
	<function>dlsym()</function>, for symbols present in the
	main executable of a process, you need to link the
	executable using the <option>-export-dynamic</option>
	option to the ELF linker (&man.ld.1;).</para>
	</answer>
	</qandaentry>

	<qandaentry>
	<question id="change-kernel-address-space">
	<para>How can I increase or reduce the kernel address space?</para>
	</question>

	<answer>
	<para>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.</para>

	<para>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.</para>

	<para>The first goal is achieved by increasing the value of
	<literal>NKPDE</literal> in
	<filename>src/sys/i386/include/pmap.h</filename>. Here is what
	it looks like for a 1 GB address space:</para>

	<programlisting>#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</programlisting>

	<para>To find the correct value of <literal>NKPDE</literal>,
	divide the desired address space size (in megabytes) by four,
	then subtract one for UP and two for SMP.</para>

	<para>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 <symbol>LOAD_ADDRESS</symbol> in
	<filename>src/sys/i386/conf/Makefile.i386</filename> to that
	value; then set the location counter in the beginning of the
	section listing in
	<filename>src/sys/i386/conf/kernel.script</filename> to the
	same value, as follows:</para>

	<programlisting>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) }</programlisting>

	<para>Then reconfig and rebuild your kernel. You will
	probably have problems with &man.ps.1; &man.top.1; and the
	like; <command>make world</command> should take care of it
	(or a manual rebuild of <filename>libkvm</filename>,
	&man.ps.1; and &man.top.1; after copying the patched
	<filename>pmap.h</filename> to
	<filename>/usr/include/vm/</filename>.</para>

	<para>NOTE: the size of the kernel address space must be a
	multiple of four megabytes.</para>

	<para>[&a.dg; adds: <emphasis>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.]</emphasis></para>
	</answer>
	</qandaentry>
	</qandaset>
	</chapter>

	<chapter id="acknowledgments">
	<title>Acknowledgments</title>

	<para>This innocent little Frequently Asked Questions document has
	been written, rewritten, edited, folded, spindled, mutilated,
	eviscerated, contemplated, discombobulated, cogitated,
	regurgitated, rebuilt, castigated, and reinvigorated over the
	last decade, by a cast of hundreds if not thousands.
	Repeatedly.</para>

	<para>We wish to thank every one of the people responsible, and we
	encourage you to to <ulink
	url="&url.articles.contributing;/article.html">join them</ulink>
	in making this FAQ even better.</para>

	</chapter>

	&bibliography;
	</book>

File Metadata

Mime Type: text/html
Expires: Wed, Nov 12, 11:45 PM (1 d, 21 h)
Storage Engine: blob
Storage Format: Raw Data
Storage Handle: 25184824
Default Alt Text: book.sgml (479 KB)

book.sgmlNo OneTemporaryActions

book.sgmlView Options

File Metadata

Event Timeline

book.sgml
No OneTemporary
Actions

book.sgml
View Options