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Index: en_US.ISO8859-1/books/handbook/boot/chapter.xml
===================================================================
--- en_US.ISO8859-1/books/handbook/boot/chapter.xml
+++ en_US.ISO8859-1/books/handbook/boot/chapter.xml
@@ -903,4 +903,42 @@
a module or statically compiled into a custom kernel.</para>
</note>
</sect1>
+
+ <sect1 xml:id="boot-reroot">
+ <title>Root remount</title>
+
+ <note>
+ <para>The reroot functionality is supported
+ starting with &os;&nbsp;11.0-RELEASE.</para>
+ </note>
+
+ <para>In some cases mounting the root filesystem requires some additional steps
+ which require working userspace. An example of this is booting from an iSCSI LUN - setting up
+ an iSCSI session requires &man.iscsid.8; and &man.iscsictl.8;. This presents
+ a chicken and egg problem. The solution is to boot with temporary root filesystem
+ on a memory disk image preloaded by &man.loader.8;, set up the kernel state as
+ neccessary, replace the temporary root file system with the proper one, and then
+ continue booting as usual.</para>
+
+ <para>First step is to create a temporary root filesystem:</para>
+ <screen><userinput>makefs /boot/reroot.img /usr/share/examples/reroot/manifest</userinput></screen>
+
+ <para>After that is done, configure the &man.loader.8; to preload it by putting
+ the following into <filename>/boot/loader.conf</filename>:</para>
+ <screen>reroot_load="YES"
+reroot_type="md_image"
+reroot_name="/boot/reroot.img"</screen>
+
+ <para>The rc script contained in the image is configured using &man.kenv.1;
+ variables, set in <filename>/boot/loader.conf</filename>, or manually from
+ &man.loader.8; prompt: reroot_iface, reroot_ifconfig, reroot_sh,
+ reroot_iscsi_target, reroot_iscsi_portal, reroot_mountfrom.</para>
+
+ <para>As an example, to mount root from an iSCSI volume, use the following:</para>
+ <screen>reroot_iface=em0
+reroot_iscsi_target=iqn.2012-06.com.example:target0
+reroot_iscsi_portal=192.168.1.5
+reroot_mountfrom=ufs:/dev/da0</screen>
+
+ </sect1>
</chapter>
Index: en_US.ISO8859-1/books/handbook/disks/chapter.xml
===================================================================
--- en_US.ISO8859-1/books/handbook/disks/chapter.xml
+++ en_US.ISO8859-1/books/handbook/disks/chapter.xml
@@ -580,6 +580,129 @@
any block device, including optical drives or
<acronym>iSCSI</acronym> <acronym>LUN</acronym>s.</para>
</sect2>
+
+ <sect2>
+ <title>USB Mass Storage Target</title>
+
+ <note>
+ <para>The &man.cfumass.4; driver is a <acronym>USB</acronym> device
+ mode driver that first became available in &os;&nbsp;12.0-CURRENT.
+ </para>
+ </note>
+
+ <para>When running on <acronym>USB OTG</acronym>-compliant hardware
+ like that built into many
+ embedded boards - the &os; <acronym>USB</acronym> stack can run in
+ device mode.
+ Device mode makes it possible to present itself as different kinds
+ of <acronym>USB</acronym> device classes, including serial ports,
+ network adapters, and mass storage. A <acronym>USB</acronym>
+ host like a laptop or desktop computer is able to access them just
+ like physical <acronym>USB</acronym> devices.</para>
+
+ <para>Device mode support uses the &man.usb.template.4; kernel module.
+ When it is is loaded, the <acronym>USB</acronym> stack switches
+ between host-side and device-side automatically, depending
+ on what is connected to the <acronym>USB</acronym> port.
+ Connecting a <acronym>USB</acronym> device like a memory stick
+ to the <acronym>USB OTG</acronym> port causes &os; to switch to host
+ mode. Connecting a <acronym>USB</acronym> host like a computer
+ causes &os; to switch to device mode.</para>
+
+ <para>What &os; presents to the <acronym>USB</acronym> host
+ depends on the <varname>hw.usb.template</varname> sysctl. See
+ &man.usb.template.4; for the list of available values. Note
+ that for the host to take notice of the configuration change,
+ it must be either physically disconnected and reconnected,
+ or forced to rescan the
+ <acronym>USB</acronym> bus in a system-specific way.
+ When &os; is running on the host, the <command>reset</command>
+ subcommand of
+ &man.usbconfig.8; command can be used. This also must be done
+ after loading <filename>usb_template.ko</filename> if the
+ <acronym>USB</acronym> host was already connected to the
+ <acronym>USB OTG</acronym> socket.</para>
+
+ <para>By default, the <varname>hw.usb.template</varname> sysctl
+ is set to 0, making &os; work as a <acronym>USB</acronym>
+ Mass Storage target. Both &man.usb.template.4; and
+ &man.cfumass.4; kernel modules must be loaded.
+ The &man.cfumass.4; interfaces to the CTL subsystem, the same one
+ that is used for <acronym>iSCSI</acronym> or Fibre Channel targets.
+ On the host side, <acronym>USB</acronym> Mass Storage initiators
+ can only access a single <acronym>LUN</acronym>,
+ LUN 0.</para>
+
+ <para><acronym>USB</acronym> Mass Storage
+ does not require the &man.ctld.8; daemon to be running, although
+ it can be used if desired. This is different from iSCSI. Thus,
+ there are two ways to configure the target: &man.ctladm.8;,
+ or &man.ctld.8;. Both require the <filename>cfumass.ko</filename>
+ kernel module to be loaded. The module can be loaded manually:</para>
+
+ <screen>&prompt.root; <userinput>kldload cfumass</userinput></screen>
+
+ <para>If the <filename>cfumass.ko</filename> kernel module
+ has not been built into kernel, the
+ <filename>/boot/loader.conf</filename> should be edited to load
+ the module at boot:</para>
+
+ <programlisting>cfumass_load="YES"</programlisting>
+
+ <para>A <acronym>LUN</acronym> can be created without &man.ctld.8;
+ daemon running:</para>
+
+ <screen>&prompt.root; <userinput>ctladm create -b block -o file=/data/target0</userinput></screen>
+
+ <para>This presents contents of the image file
+ <filename>/data/target0</filename> as a <acronym>LUN</acronym> to the
+ <acronym>USB</acronym> host. The file must exist before executing
+ the command. To configure the <acronym>LUN</acronym> at system startup,
+ add the command to <filename>/etc/rc.local</filename>.</para>
+
+ <para>&man.ctld.8; can also be used to manage <acronym>LUN</acronym>s. Create
+ <filename>/etc/ctl.conf</filename>, add a line to <filename>/etc/rc.conf</filename>
+ to make sure the &man.ctld.8; daemon is automatically started at boot, and then
+ start the daemon.</para>
+
+ <para>The following is an example of a simple
+ <filename>/etc/ctl.conf</filename> configuration file. Refer
+ to &man.ctl.conf.5; for a more complete description of this
+ file's available options.</para>
+ <programlisting>target naa.50015178f369f092 {
+ lun 0 {
+ path /data/target0
+ size 4G
+ }
+}</programlisting>
+
+ <para>This creates a single target with a single <acronym>LUN</acronym>.
+ The <literal>naa.50015178f369f092</literal> is a device
+ identifier It is made of random 32 hexadecimal digits.
+ The <literal>path /data/target0-0</literal> line
+ defines the full path to a file or zvol backing the
+ <acronym>LUN</acronym>. That file must exist before starting
+ &man.ctld.8;. The second line is optional and specifies the
+ size of the <acronym>LUN</acronym>.</para>
+
+ <para>To make sure the &man.ctld.8; daemon is started at
+ boot, add this line to
+ <filename>/etc/rc.conf</filename>:</para>
+
+ <programlisting>ctld_enable="YES"</programlisting>
+
+ <para>To start &man.ctld.8; now, run this command:</para>
+
+ <screen>&prompt.root; <userinput>service ctld start</userinput></screen>
+
+ <para>As the &man.ctld.8; daemon is started, it reads
+ <filename>/etc/ctl.conf</filename>. If this file is edited
+ after the daemon starts, reload the changes so they take
+ effect immediately:</para>
+
+ <screen>&prompt.root; <userinput>service ctld reload</userinput></screen>
+
+ </sect2>
</sect1>
<sect1 xml:id="creating-cds">
Index: share/xml/man-refs.ent
===================================================================
--- share/xml/man-refs.ent
+++ share/xml/man-refs.ent
@@ -7060,6 +7060,7 @@
<!ENTITY man.central.4 "<citerefentry xmlns='http://docbook.org/ns/docbook'><refentrytitle>central</refentrytitle><manvolnum>4</manvolnum></citerefentry>">
<!ENTITY man.cfi.4 "<citerefentry xmlns='http://docbook.org/ns/docbook'><refentrytitle>cfi</refentrytitle><manvolnum>4</manvolnum></citerefentry>">
<!ENTITY man.cfid.4 "<citerefentry xmlns='http://docbook.org/ns/docbook'><refentrytitle>cfid</refentrytitle><manvolnum>4</manvolnum></citerefentry>">
+<!ENTITY man.cfumass.4 "<citerefentry xmlns='http://docbook.org/ns/docbook'><refentrytitle>cfumass</refentrytitle><manvolnum>4</manvolnum></citerefentry>">
<!ENTITY man.ch.4 "<citerefentry xmlns='http://docbook.org/ns/docbook'><refentrytitle>ch</refentrytitle><manvolnum>4</manvolnum></citerefentry>">
<!ENTITY man.ciss.4 "<citerefentry xmlns='http://docbook.org/ns/docbook'><refentrytitle>ciss</refentrytitle><manvolnum>4</manvolnum></citerefentry>">
<!ENTITY man.clkbrd.4 "<citerefentry xmlns='http://docbook.org/ns/docbook'><refentrytitle>clkbrd</refentrytitle><manvolnum>4</manvolnum></citerefentry>">

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