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-rw-r--r--en_US.ISO8859-1/books/handbook/boot/chapter.xml197
1 files changed, 104 insertions, 93 deletions
diff --git a/en_US.ISO8859-1/books/handbook/boot/chapter.xml b/en_US.ISO8859-1/books/handbook/boot/chapter.xml
index 2f4f619f34..c13bec3bbb 100644
--- a/en_US.ISO8859-1/books/handbook/boot/chapter.xml
+++ b/en_US.ISO8859-1/books/handbook/boot/chapter.xml
@@ -16,9 +16,9 @@
<para>The process of starting a computer and loading the operating
system is referred to as <quote>the bootstrap process</quote>,
- or simply <quote>booting</quote>. &os;'s boot process
- provides a great deal of flexibility in customizing what happens
- when the system starts, including the ability to select from
+ or simply <quote>booting</quote>. &os;'s boot process provides
+ a great deal of flexibility in customizing what happens when
+ the system starts, including the ability to select from
different operating systems installed on the same computer,
different versions of the same operating system, or a different
installed kernel.</para>
@@ -73,47 +73,54 @@
to the mechanism used to load the operating system, which has
become shortened to <quote>booting</quote>.</para>
- <indexterm><primary>BIOS</primary></indexterm>
+ <indexterm><primary><acronym>BIOS</acronym></primary></indexterm>
<indexterm>
<primary>Basic Input/Output System</primary>
- <see>BIOS</see>
+ <see><acronym>BIOS</acronym></see>
</indexterm>
- <para>On x86 hardware the Basic Input/Output System (BIOS) is
- responsible for loading the operating system. To do this, the
- BIOS looks on the hard disk for the Master Boot Record (MBR),
- which must be located on a specific place on the disk. The BIOS
- has enough knowledge to load and run the MBR, and assumes that
- the MBR can then carry out the rest of the tasks involved in
- loading the operating system, possibly with the help of the
- BIOS.</para>
+ <para>On x86 hardware the Basic Input/Output System
+ (<acronym>BIOS</acronym>) is responsible for loading the
+ operating system. To do this, the <acronym>BIOS</acronym>
+ looks on the hard disk for the Master Boot Record
+ (<acronym>MBR</acronym>), which must be located in a specific
+ place on the disk. The <acronym>BIOS</acronym> has enough
+ knowledge to load and run the <acronym>MBR</acronym>, and
+ assumes that the <acronym>MBR</acronym> can then carry out the
+ rest of the tasks involved in loading the operating system,
+ possibly with the help of the <acronym>BIOS</acronym>.</para>
- <indexterm><primary>Master Boot Record (MBR)</primary></indexterm>
+ <indexterm><primary>Master Boot Record
+ <acronym>MBR</acronym>)</primary></indexterm>
<indexterm><primary>Boot Manager</primary></indexterm>
<indexterm><primary>Boot Loader</primary></indexterm>
- <para>The code within the MBR is usually referred to as a
- <emphasis>boot manager</emphasis>, especially when it interacts
- with the user. In this case the boot manager usually has more
- code in the first <emphasis>track</emphasis> of the disk or
- within some OS's file system. (A boot manager is sometimes also
- called a <emphasis>boot loader</emphasis>, but &os; uses that
- term for a later stage of booting.) Popular boot managers
- include <application>boot0</application> (aka
+ <para>The code within the <acronym>MBR</acronym> is usually
+ referred to as a <emphasis>boot manager</emphasis>, especially
+ when it interacts with the user. In this case, the boot
+ manager usually has more code in the first
+ <emphasis>track</emphasis> of the disk or within the file
+ system of some operating systems. A boot manager is sometimes
+ also called a <emphasis>boot loader</emphasis>, but &os; uses
+ that term for a later stage of booting. Popular boot managers
+ include <application>boot0</application>, also called
<application>Boot Easy</application>, the standard &os; boot
- manager), <application>Grub</application>,
+ manager, <application>Grub</application>,
<application>GAG</application>, and
- <application>LILO</application>. (Only
- <application>boot0</application> fits within the MBR.)</para>
+ <application>LILO</application>. Only
+ <application>boot0</application> fits within the
+ <acronym>MBR</acronym>.</para>
- <para>If only one operating system is installed, a standard PC MBR
- will suffice. This MBR searches for the first bootable (active)
+ <para>If only one operating system is installed, a standard PC
+ <acronym>MBR</acronym> will suffice. This
+ <acronym>MBR</acronym> searches for the first bootable (active)
slice on the disk, and then runs the code on that slice to load
- the remainder of the operating system. By default, the MBR
- installed by &man.fdisk.8; is such an MBR and is based on
+ the remainder of the operating system. By default, the
+ <acronym>MBR</acronym> installed by &man.fdisk.8; is such an
+ <acronym>MBR</acronym> and is based on
<filename>/boot/mbr</filename>.</para>
<para>If multiple operating systems are present, a different boot
@@ -122,18 +129,18 @@
boot managers are discussed in the next subsection.</para>
<para>The remainder of the &os; bootstrap system is divided
- into three stages. The first stage is run by the MBR, which
- knows just enough to get the computer into a specific state and
- run the second stage. The second stage can do a little bit
- more, before running the third stage. The third stage finishes
- the task of loading the operating system. The work is split
- into three stages because PC standards put limits on the size of
- the programs that can be run at stages one and two. Chaining
- the tasks together allows &os; to provide a more flexible
- loader.</para>
+ into three stages. The first stage is run by the
+ <acronym>MBR</acronym>, which knows just enough to get the
+ computer into a specific state and run the second stage. The
+ second stage can do a little bit more, before running the
+ third stage. The third stage finishes the task of loading the
+ operating system. The work is split into three stages because
+ PC standards put limits on the size of the programs that can
+ be run at stages one and two. Chaining the tasks together
+ allows &os; to provide a more flexible loader.</para>
<indexterm><primary>kernel</primary></indexterm>
- <indexterm><primary><command>init</command></primary></indexterm>
+ <indexterm><primary>&man.init.8;</primary></indexterm>
<para>The kernel is then started and it begins to probe for
devices and initialize them for use. Once the kernel boot
@@ -154,11 +161,11 @@
<title>The Boot Manager</title>
<indexterm><primary>Master Boot Record
- (MBR)</primary></indexterm>
+ (<acronym>MBR</acronym>)</primary></indexterm>
- <para>The code in the MBR or boot manager is sometimes referred
- to as <emphasis>stage zero</emphasis> of the boot process.
- This section discusses two boot managers:
+ <para>The code in the <acronym>MBR</acronym> or boot manager is
+ sometimes referred to as <emphasis>stage zero</emphasis> of
+ the boot process. This section discusses two boot managers:
<application>boot0</application> and
<application>LILO</application>.</para>
@@ -166,12 +173,12 @@
<title>The <application>boot0</application> Boot
Manager:</title>
- <para>The MBR installed by &os;'s installer or
- &man.boot0cfg.8; is based on
+ <para>The <acronym>MBR</acronym> installed by &os;'s installer
+ or &man.boot0cfg.8; is based on
<filename>/boot/boot0</filename>. The size and capability
of <application>boot0</application> is restricted to 446
bytes due to the slice table and <literal>0x55AA</literal>
- identifier at the end of the MBR. If
+ identifier at the end of the <acronym>MBR</acronym>. If
<application>boot0</application> and multiple operating
systems are installed, a message similar to this example
will be displayed at boot time:</para>
@@ -187,18 +194,22 @@ Default: F2</screen>
</example>
<para>Other operating systems, in particular &windows;, will
- overwrite an existing MBR if they are installed after &os;.
- If this happens, or you want to replace the existing MBR
- with the &os; MBR, use the following command:</para>
+ overwrite an existing <acronym>MBR</acronym> if they are
+ installed after &os;. If this happens, or to replace the
+ existing <acronym>MBR</acronym> with the &os;
+ <acronym>MBR</acronym>, use the following command:</para>
<screen>&prompt.root; <userinput>fdisk -B -b /boot/boot0 <replaceable>device</replaceable></userinput></screen>
<para>where <replaceable>device</replaceable> is the boot disk,
- such as <devicename>ad0</devicename> for the first IDE disk,
- <devicename>ad2</devicename> for the first IDE disk on a
- second IDE controller, or <devicename>da0</devicename>
- for the first SCSI disk. To create a custom configuration of
- the MBR, refer to &man.boot0cfg.8;.</para>
+ such as <devicename>ad0</devicename> for the first
+ <acronym>IDE</acronym> disk, <devicename>ad2</devicename>
+ for the first <acronym>IDE</acronym> disk on a second
+ <acronym>IDE</acronym> controller, or
+ <devicename>da0</devicename>
+ for the first <acronym>SCSI</acronym> disk. To create a
+ custom configuration of the <acronym>MBR</acronym>, refer to
+ &man.boot0cfg.8;.</para>
<formalpara>
<title>The LILO Boot Manager:</title>
@@ -235,11 +246,11 @@ label=FreeBSD</programlisting>
constraints, they have been split into two, but are always
installed together. They are copied from the combined
<filename>/boot/boot</filename> by the installer or
- <application>bsdlabel</application>.</para>
+ &man.bsdlabel.8;.</para>
<para>They are located outside file systems, in the first track
of the boot slice, starting with the first sector. This is
- where <link linkend="boot-boot0">boot0</link>, or any other
+ where boot0 (<xref linkend="boot-boot0"/>), or any other
boot manager, expects to find a program to run which will
continue the boot process. The number of sectors used is
easily determined from the size of
@@ -256,9 +267,9 @@ label=FreeBSD</programlisting>
can provide a simple interface to choose the kernel or loader
to run.</para>
- <para><link linkend="boot-loader">loader</link> is much more
- sophisticated and provides a boot configuration which is run
- by <filename>boot2</filename>.</para>
+ <para>However, &man.loader.8; is much more sophisticated and
+ provides a boot configuration which is run by
+ <filename>boot2</filename>.</para>
<example id="boot-boot2-example">
<title><filename>boot2</filename> Screenshot</title>
@@ -276,7 +287,8 @@ boot:</screen>
<para>where <replaceable>diskslice</replaceable> is the disk and
slice to boot from, such as <devicename>ad0s1</devicename>
- for the first slice on the first IDE disk.</para>
+ for the first slice on the first <acronym>IDE</acronym>
+ disk.</para>
<warning>
<title>Dangerously Dedicated Mode</title>
@@ -557,10 +569,10 @@ boot:</screen>
first is the default legacy virtual console command line
environment. After the system finishes booting, a console
login prompt is presented. The second environment is the
- graphical environment provided by
- <link linkend="x11">Xorg</link>. Refer to that chapter for
- more information on how to install and configure a graphical
- display manager and a graphical login manager.</para>
+ graphical environment as described in <xref linkend="x11"/>.
+ Refer to that chapter for more information on how to install
+ and configure a graphical display manager and a graphical
+ login manager.</para>
<sect4 id="boot-splash-function">
<title>Splash Screen Function</title>
@@ -574,8 +586,8 @@ boot:</screen>
<para>To use larger images, up to the maximum resolution of
1024 by 768 pixels, load the <acronym>VESA</acronym>
- module during system boot. For a <ulink
- url="kernelconfig">custom kernel</ulink>, include the
+ module during system boot. For a custom kernel, as
+ described in <xref linkend="kernelconfig"/>, include the
<literal>VESA</literal> kernel configuration option.
Loading <acronym>VESA</acronym> support provides the
ability to display a splash screen image that fills the
@@ -666,8 +678,8 @@ bitmap_name="<replaceable>/boot/splash.bin</replaceable>"</programlisting>
or
<filename><replaceable>bluewave</replaceable>.pcx</filename>.</para>
- <para>Other interesting
- <filename>loader.conf</filename> options include:</para>
+ <para>Other interesting <filename>loader.conf</filename>
+ options include:</para>
<variablelist>
<varlistentry>
@@ -710,10 +722,10 @@ bitmap_name="<replaceable>/boot/splash.bin</replaceable>"</programlisting>
<secondary>boot interaction</secondary>
</indexterm>
- <para>Once the kernel is loaded by either the default <link
- linkend="boot-loader">loader</link> or by <link
- linkend="boot-boot1">boot2</link> which bypasses the loader,
- it examines its boot flags, if any, and adjusts its behavior as
+ <para>Once the kernel is loaded by either the default loader
+ (<xref linkend="boot-loader"/>) or by boot2 (<xref
+ linkend="boot-boot1"/>), which bypasses the loader, it
+ examines any boot flags and adjusts its behavior as
necessary.</para>
<sect2 id="boot-kernel-bootflags">
@@ -807,8 +819,9 @@ bitmap_name="<replaceable>/boot/splash.bin</replaceable>"</programlisting>
<quote>device hints</quote>. These <quote>device hints</quote>
are used by device drivers for device configuration.</para>
- <para>Device hints may also be specified at the <link
- linkend="boot-loader"> Stage 3 boot loader</link> prompt.
+ <para>Device hints may also be specified at the Stage 3 boot
+ loader prompt, as demonstrated in <xref
+ linkend="boot-loader"/>.
Variables can be added using <command>set</command>, removed
with <command>unset</command>, and viewed
<command>show</command>. Variables set in
@@ -882,7 +895,7 @@ bitmap_name="<replaceable>/boot/splash.bin</replaceable>"</programlisting>
<title>Init: Process Control Initialization</title>
<indexterm>
- <primary><command>init</command></primary>
+ <primary>&man.init.8;</primary>
</indexterm>
<para>Once the kernel has finished booting, it passes control to
@@ -897,10 +910,9 @@ bitmap_name="<replaceable>/boot/splash.bin</replaceable>"</programlisting>
<para>The automatic reboot sequence makes sure that the file
systems available on the system are consistent. If they are
not, and &man.fsck.8; cannot fix the inconsistencies of a UFS
- file system, &man.init.8; drops the system into
- <link linkend="boot-singleuser">single-user mode</link> so
- that the system administrator can resolve the problem
- directly.</para>
+ file system, &man.init.8; drops the system into single-user
+ mode (<xref linkend="boot-singleuser"/>) so that the system
+ administrator can resolve the problem directly.</para>
</sect2>
<sect2 id="boot-singleuser">
@@ -909,14 +921,13 @@ bitmap_name="<replaceable>/boot/splash.bin</replaceable>"</programlisting>
<indexterm><primary>single-user mode</primary></indexterm>
<indexterm><primary>console</primary></indexterm>
- <para>This mode can be reached through the <link
- linkend="boot-autoreboot">automatic reboot sequence</link>,
- the user booting with <option>-s</option>, or by setting
- the <envar>boot_single</envar> variable in
- <command>loader</command>.</para>
+ <para>This mode can be reached through the automatic reboot
+ sequence (<xref linkend="boot-autoreboot"/>), the user booting
+ with <option>-s</option>, or by setting the <envar>boot_
+ single</envar> variable in &man.loader.8;.</para>
<para>It can also be reached by calling &man.shutdown.8; from
- <link linkend="boot-multiuser">multi-user mode</link> without
+ multi-user mode (<xref linkend="boot-multiuser"/>) without
including <option>-r</option> or <option>-h</option>.</para>
<para>If the system <literal>console</literal> is set to
@@ -952,13 +963,13 @@ console none unknown off insecure</programlisting>
<indexterm><primary>multi-user mode</primary></indexterm>
<para>If &man.init.8; finds the file systems to be in order, or
- once the user has finished their commands in <link
- linkend="boot-singleuser">single-user mode</link>, the
- system enters multi-user mode, in which it starts the
- resource configuration of the system.</para>
+ once the user has finished their commands in single-user
+ mode (<xref linkend="boot-singleuser"/>), the system enters
+ multi-user mode, in which it starts the resource configuration
+ of the system.</para>
<sect3 id="boot-rc">
- <title>Resource Configuration (rc)</title>
+ <title>Resource Configuration</title>
<indexterm><primary>rc files</primary></indexterm>
@@ -983,7 +994,7 @@ console none unknown off insecure</programlisting>
<title>Shutdown Sequence</title>
<indexterm>
- <primary><command>shutdown</command></primary>
+ <primary>&man.shutdown.8;</primary>
</indexterm>
<para>Upon controlled shutdown using &man.shutdown.8;,
@@ -997,8 +1008,8 @@ console none unknown off insecure</programlisting>
that support power management, use <command>shutdown -p
now</command> to turn the power off immediately. To reboot a
&os; system, use <command>shutdown -r now</command>. One must
- be <username>root</username> or a member of the
- <groupname>operator</groupname> group in order to run
+ be <username>root</username> or a member of
+ <groupname>operator</groupname> in order to run
&man.shutdown.8;. One can also use &man.halt.8; and
&man.reboot.8;. Refer to their manual pages and to
&man.shutdown.8; for more information.</para>