X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=man%2Fbootup.xml;h=b5c3e1523a91f675d315fbc593cd18d2ee231797;hb=798d3a524ea57aaf40cb53858aaa45ec702f012d;hp=6bd22ef476c73743e6a441fc9691f45ddf48451c;hpb=9e5f0f92915b777308797294c6e103e430957b5d;p=elogind.git

diff --git a/man/bootup.xml b/man/bootup.xml
index 6bd22ef47..b5c3e1523 100644
--- a/man/bootup.xml
+++ b/man/bootup.xml
@@ -1,6 +1,6 @@
 <?xml version='1.0'?> <!--*-nxml-*-->
 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
-        "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
 
 <!--
   This file is part of systemd.
@@ -23,278 +23,279 @@
 
 <refentry id="bootup">
 
-        <refentryinfo>
-                <title>bootup</title>
-                <productname>systemd</productname>
-
-                <authorgroup>
-                        <author>
-                                <contrib>Developer</contrib>
-                                <firstname>Lennart</firstname>
-                                <surname>Poettering</surname>
-                                <email>lennart@poettering.net</email>
-                        </author>
-                </authorgroup>
-        </refentryinfo>
-
-        <refmeta>
-                <refentrytitle>bootup</refentrytitle>
-                <manvolnum>7</manvolnum>
-        </refmeta>
-
-        <refnamediv>
-                <refname>bootup</refname>
-                <refpurpose>System bootup process</refpurpose>
-        </refnamediv>
-
-        <refsect1>
-                <title>Description</title>
-
-                <para>A number of different components are involved in the
-                system boot. Immediately after power-up, the system
-                BIOS will do minimal hardware initialization, and hand
-                control over to a boot loader stored on a persistent
-                storage device. This boot loader will then invoke an
-                OS kernel from disk (or the network). In the Linux
-                case this kernel now (optionally) extracts and
-                executes an initial RAM disk image (initrd) such as
-                <citerefentry><refentrytitle>dracut</refentrytitle><manvolnum>8</manvolnum></citerefentry>
-                which looks for the root file system. After the root
-                file system is found and mounted the initrd hands over
-                control to the system manager (such as
-                <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>)
-                stored on the OS image which is then responsible for
-                probing all remaining hardware, mounting all necessary
-                file systems and spawning all configured
-                services.</para>
-
-                <para>On shutdown the system manager stops all
-                services, unmounts all file systems (detaching the
-                storage technologies backing them), and then
-                (optionally) jumps back into the initrd code which
-                unmounts/detaches the root file system and the storage
-                it resides on. As last step the system is powered down.</para>
-
-                <para>Additional information about the system boot
-                process may be found in
-                <citerefentry><refentrytitle>boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
-        </refsect1>
-
-        <refsect1>
-                <title>System Manager Bootup</title>
-
-                <para>At boot, the system manager on the OS image is
-                responsible for initializing the required file
-                systems, services and drivers that are necessary for
-                operation of the system. On
-                <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
-                systems this process is split up in various discrete
-                steps which are exposed as target units. (See
-                <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-                for detailed information about target units.) The
-                boot-up process is highly parallelized so that the
-                order in which specific target units are reached is not
-                deterministic, but still adheres to a limited amount
-                of ordering structure.</para>
-
-                <para>When systemd starts up the system it will
-                activate all units that are dependencies of
-                <filename>default.target</filename> (as well as
-                recursively all dependencies of these
-                dependencies). Usually
-                <filename>default.target</filename> is simply an alias
-                of <filename>graphical.target</filename> or
-                <filename>multi-user.target</filename> depending on
-                whether the system is configured for a graphical UI or
-                only for a text console. To enforce minimal ordering
-                between the units pulled in a number of well-known
-                target units are available, as listed on
-                <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
-
-                <para>The following chart is a structural overview of
-                these well-known units and their position in the
-                boot-up logic. The arrows describe which units are
-                pulled in and ordered before which other units. Units
-                near the top are started before units nearer to the
-                bottom of the chart.</para>
+  <refentryinfo>
+    <title>bootup</title>
+    <productname>systemd</productname>
+
+    <authorgroup>
+      <author>
+        <contrib>Developer</contrib>
+        <firstname>Lennart</firstname>
+        <surname>Poettering</surname>
+        <email>lennart@poettering.net</email>
+      </author>
+    </authorgroup>
+  </refentryinfo>
+
+  <refmeta>
+    <refentrytitle>bootup</refentrytitle>
+    <manvolnum>7</manvolnum>
+  </refmeta>
+
+  <refnamediv>
+    <refname>bootup</refname>
+    <refpurpose>System bootup process</refpurpose>
+  </refnamediv>
+
+  <refsect1>
+    <title>Description</title>
+
+    <para>A number of different components are involved in the system
+    boot. Immediately after power-up, the system BIOS will do minimal
+    hardware initialization, and hand control over to a boot loader
+    stored on a persistent storage device. This boot loader will then
+    invoke an OS kernel from disk (or the network). In the Linux case,
+    this kernel (optionally) extracts and executes an initial RAM disk
+    image (initrd), such as generated by
+    <citerefentry project='die-net'><refentrytitle>dracut</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+    which looks for the root file system (possibly using
+    <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+    for this). After the root file system is found and mounted, the
+    initrd hands over control to the host's system manager (such as
+    <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>)
+    stored on the OS image, which is then responsible for probing all
+    remaining hardware, mounting all necessary file systems and
+    spawning all configured services.</para>
+
+    <para>On shutdown, the system manager stops all services, unmounts
+    all file systems (detaching the storage technologies backing
+    them), and then (optionally) jumps back into the initrd code which
+    unmounts/detaches the root file system and the storage it resides
+    on. As a last step, the system is powered down.</para>
+
+    <para>Additional information about the system boot process may be
+    found in
+    <citerefentry project='man-pages'><refentrytitle>boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
+  </refsect1>
+
+  <refsect1>
+    <title>System Manager Bootup</title>
+
+    <para>At boot, the system manager on the OS image is responsible
+    for initializing the required file systems, services and drivers
+    that are necessary for operation of the system. On
+    <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+    systems, this process is split up in various discrete steps which
+    are exposed as target units. (See
+    <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+    for detailed information about target units.) The boot-up process
+    is highly parallelized so that the order in which specific target
+    units are reached is not deterministic, but still adheres to a
+    limited amount of ordering structure.</para>
+
+    <para>When systemd starts up the system, it will activate all
+    units that are dependencies of <filename>default.target</filename>
+    (as well as recursively all dependencies of these dependencies).
+    Usually, <filename>default.target</filename> is simply an alias of
+    <filename>graphical.target</filename> or
+    <filename>multi-user.target</filename>, depending on whether the
+    system is configured for a graphical UI or only for a text
+    console. To enforce minimal ordering between the units pulled in,
+    a number of well-known target units are available, as listed on
+    <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
+
+    <para>The following chart is a structural overview of these
+    well-known units and their position in the boot-up logic. The
+    arrows describe which units are pulled in and ordered before which
+    other units. Units near the top are started before units nearer to
+    the bottom of the chart.</para>
 
 <programlisting>local-fs-pre.target
-         |
-         v
+   |
+   v
 (various mounts and   (various swap   (various cryptsetup
- fsck services...)     devices...)        devices...)       (various low-level   (various low-level
-         |                  |                  |             services: udevd,     API VFS mounts:
-         v                  v                  v             tmpfiles, random     mqueue, configfs,
+ fsck services...)     devices...)  devices...)       (various low-level   (various low-level
+   |      |      |       services: udevd,     API VFS mounts:
+   v      v      v       tmpfiles, random     mqueue, configfs,
   local-fs.target      swap.target     cryptsetup.target    seed, sysctl, ...)      debugfs, ...)
-         |                  |                  |                    |                    |
-         \__________________|_________________ | ___________________|____________________/
-                                              \|/
-                                               v
-                                        sysinit.target
-                                               |
-                             _________________/|\___________________
-                            /                  |                    \
-                            |                  |                    |
-                            v                  |                    v
-                        (various               |              rescue.service
-                       sockets...)             |                    |
-                            |                  |                    v
-                            v                  |              <emphasis>rescue.target</emphasis>
-                     sockets.target            |
-                            |                  |
-                            \_________________ |
-                                              \|
-                                               v
-                                         basic.target
-                                               |
-            __________________________________/|                                 emergency.service
-           /                |                  |                                         |
-           |                |                  |                                         v
-           v                v                  v                                 <emphasis>emergency.target</emphasis>
-       display-      (various system    (various system
-   manager.service       services           services)
-           |           required for            |
-           |          graphical UIs)           v
-           |                |           <emphasis>multi-user.target</emphasis>
-           |                |                  |
-           \_______________ | _________________/
-                           \|/
-                            v
-                    <emphasis>graphical.target</emphasis></programlisting>
-
-                <para>Target units that are commonly used as boot
-                targets are <emphasis>emphasized</emphasis>. These
-                units are good choices as goal targets, for
-                example by passing them to the
-                <varname>systemd.unit=</varname> kernel command line
-                option (see
-                <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>)
-                or by symlinking <filename>default.target</filename>
-                to them.</para>
-        </refsect1>
-
-        <refsect1>
-                <title>Systemd in the Initrd</title>
-                <para>If the initrd creation tool used the services provided
-                by systemd, the default target in the initrd is the
-                initrd-fs.target. The process is the same as above until the basic.target is reached.
-                Systemd now continues to the initrd.target. If the root device could be mounted
-                on /sysroot, the sysroot.mount unit is active and the initrd-root-fs.target is reached.
-                initrd-parse-etc.service scans /sysroot/etc/fstab for the /usr mountpoint and for entries
-                marked with the <emphasis>x-initrd.mount</emphasis> option set. If these mountpoint are
-                mounted in /sysroot, the initrd-fs.target is reached.
-                The initrd-cleanup.service isolates to the initrd-switch-root.target,
-                where cleanup services can run. At the very last end
-                initrd-switch-root.service is activated, which will cause
-                the system to switch root to /sysroot.
-                </para>
-
-<programlisting>
-                                        (same as above)
-                                               :
-                                               :
-                                               v
-                                         basic.target
-                                               |                                 emergency.service
-                        ______________________/|                                         |
-                       /                       |                                         v
-                       |                  sysroot.mount                          <emphasis>emergency.target</emphasis>
-                       |                       |
-                       |                       v
-                       |             initrd-root-fs.target
-                       |                       |
-                       |                       v
-                       |            initrd-parse-etc.service
-           (custom initrd services)            |
-                       |                       v
-                       |            (sysroot-usr.mount and
-                       |             various mounts marked
-                       |               with fstab option
-                       |                x-initrd.mount)
-                       |                       |
-                       |                       v
-                       |                initrd-fs.target
-                       |                       |
-                       \______________________ |
-                                              \|
-                                               v
-                                          initrd.target
-                                               |
-                                               v
-                                     initrd-cleanup.service
-                                          isolates to
-                                    initrd-switch-root.target
-                                               |
-                                               v
-                        ______________________/|
-                       /                       |
-                       |        initrd-udevadm-cleanup-db.service
-                       |                       |
-           (custom initrd services)            |
-                       |                       |
-                       \______________________ |
-                                              \|
-                                               v
-                                   initrd-switch-root.target
-                                               |
-                                               v
-                                   initrd-switch-root.service
-                                               |
-                                               v
-                                          switch-root
-</programlisting>
-        </refsect1>
-
-
-        <refsect1>
-                <title>System Manager Shutdown</title>
-
-                <para>System shutdown also consists of various target
-                units with some minimal ordering structure
-                applied:</para>
-
-
-
-
-<programlisting>                                  (conflicts with  (conflicts with
-                                    all system     all file system
-                                     services)     mounts, swaps,
-                                         |           cryptsetup
-                                         |          devices, ...)
-                                         |                |
-                                         v                v
-                                  shutdown.target    umount.target
-                                         |                |
-                                         \_______   ______/
-                                                 \ /
-                                                  v
-                                         (various low-level
-                                              services)
-                                                  |
-                                                  v
-                                            final.target
-                                                  |
-            _____________________________________/ \_________________________________
-           /                         |                        |                      \
-           |                         |                        |                      |
-           v                         v                        v                      v
+   |      |      |        |        |
+   \__________________|_________________ | ___________________|____________________/
+                \|/
+                 v
+          sysinit.target
+                 |
+    ____________________________________/|\________________________________________
+   /      |      |        |        \
+   |      |      |        |        |
+   v      v      |        v        v
+     (various     (various         |    (various    rescue.service
+    timers...)    paths...)        |         sockets...)         |
+   |      |      |        |        v
+   v      v      |        v        <emphasis>rescue.target</emphasis>
+   timers.target      paths.target       |       sockets.target
+   |      |      |        |
+   v      |_________________ | ___________________/
+                \|/
+                 v
+           basic.target
+                 |
+    ____________________________________/|         emergency.service
+   /      |      |           |
+   |      |      |           v
+   v      v      v         <emphasis>emergency.target</emphasis>
+     display-  (various system    (various system
+ manager.service   services     services)
+   |       required for      |
+   |      graphical UIs)     v
+   |      |     <emphasis>multi-user.target</emphasis>
+   |      |      |
+   \_________________ | _________________/
+         \|/
+          v
+      <emphasis>graphical.target</emphasis></programlisting>
+
+    <para>Target units that are commonly used as boot targets are
+    <emphasis>emphasized</emphasis>. These units are good choices as
+    goal targets, for example by passing them to the
+    <varname>systemd.unit=</varname> kernel command line option (see
+    <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>)
+    or by symlinking <filename>default.target</filename> to
+    them.</para>
+
+    <para><filename>timers.target</filename> is pulled-in by
+    <filename>basic.target</filename> asynchronously. This allows
+    timers units to depend on services which become only available
+    later in boot.</para>
+  </refsect1>
+
+  <refsect1>
+    <title>Bootup in the Initial RAM Disk (initrd)</title>
+    <para>The initial RAM disk implementation (initrd) can be set up
+    using systemd as well. In this case, boot up inside the initrd
+    follows the following structure.</para>
+
+    <para>The default target in the initrd is
+    <filename>initrd.target</filename>. The bootup process begins
+    identical to the system manager bootup (see above) until it
+    reaches <filename>basic.target</filename>. From there, systemd
+    approaches the special target <filename>initrd.target</filename>.
+    If the root device can be mounted at
+    <filename>/sysroot</filename>, the
+    <filename>sysroot.mount</filename> unit becomes active and
+    <filename>initrd-root-fs.target</filename> is reached. The service
+    <filename>initrd-parse-etc.service</filename> scans
+    <filename>/sysroot/etc/fstab</filename> for a possible
+    <filename>/usr</filename> mount point and additional entries
+    marked with the <emphasis>x-initrd.mount</emphasis> option. All
+    entries found are mounted below <filename>/sysroot</filename>, and
+    <filename>initrd-fs.target</filename> is reached. The service
+    <filename>initrd-cleanup.service</filename> isolates to the
+    <filename>initrd-switch-root.target</filename>, where cleanup
+    services can run. As the very last step, the
+    <filename>initrd-switch-root.service</filename> is activated,
+    which will cause the system to switch its root to
+    <filename>/sysroot</filename>.
+    </para>
+
+<programlisting>                 : (beginning identical to above)
+                 :
+                 v
+           basic.target
+                 |         emergency.service
+      ______________________/|           |
+           /           |           v
+           |      sysroot.mount        <emphasis>emergency.target</emphasis>
+           |           |
+           |           v
+           |       initrd-root-fs.target
+           |           |
+           |           v
+           v      initrd-parse-etc.service
+    (custom initrd     |
+     services...)      v
+           |      (sysroot-usr.mount and
+           |       various mounts marked
+           |         with fstab option
+           |        x-initrd.mount...)
+           |           |
+           |           v
+           |    initrd-fs.target
+           \______________________ |
+                \|
+                 v
+            initrd.target
+                 |
+                 v
+             initrd-cleanup.service
+            isolates to
+            initrd-switch-root.target
+                 |
+                 v
+      ______________________/|
+           /           v
+           |  initrd-udevadm-cleanup-db.service
+           v           |
+    (custom initrd     |
+     services...)      |
+           \______________________ |
+                \|
+                 v
+           initrd-switch-root.target
+                 |
+                 v
+           initrd-switch-root.service
+                 |
+                 v
+             Transition to Host OS</programlisting>
+  </refsect1>
+
+
+  <refsect1>
+    <title>System Manager Shutdown</title>
+
+    <para>System shutdown with systemd also consists of various target
+    units with some minimal ordering structure applied:</para>
+
+<programlisting>          (conflicts with  (conflicts with
+            all system     all file system
+             services)     mounts, swaps,
+           |     cryptsetup
+           |    devices, ...)
+           |    |
+           v    v
+          shutdown.target    umount.target
+           |    |
+           \_______   ______/
+             \ /
+              v
+           (various low-level
+                services)
+              |
+              v
+              final.target
+              |
+      _____________________________________/ \_________________________________
+     /       |      |          \
+     |       |      |          |
+     v       v      v          v
 systemd-reboot.service   systemd-poweroff.service   systemd-halt.service   systemd-kexec.service
-           |                         |                        |                      |
-           v                         v                        v                      v
-    <emphasis>reboot.target</emphasis>             <emphasis>poweroff.target</emphasis>            <emphasis>halt.target</emphasis>           <emphasis>kexec.target</emphasis></programlisting>
-
-                <para>Commonly used system shutdown targets are <emphasis>emphasized</emphasis>.</para>
-        </refsect1>
-
-        <refsect1>
-                <title>See Also</title>
-                <para>
-                        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
-                        <citerefentry><refentrytitle>boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
-                        <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
-                        <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
-                        <citerefentry><refentrytitle>dracut</refentrytitle><manvolnum>8</manvolnum></citerefentry>
-                </para>
-        </refsect1>
+     |       |      |          |
+     v       v      v          v
+    <emphasis>reboot.target</emphasis>       <emphasis>poweroff.target</emphasis>      <emphasis>halt.target</emphasis>     <emphasis>kexec.target</emphasis></programlisting>
+
+    <para>Commonly used system shutdown targets are
+    <emphasis>emphasized</emphasis>.</para>
+  </refsect1>
+
+  <refsect1>
+    <title>See Also</title>
+    <para>
+      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+      <citerefentry project='man-pages'><refentrytitle>boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+      <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+      <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+      <citerefentry project='die-net'><refentrytitle>dracut</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+    </para>
+  </refsect1>
 
 </refentry>