<?xml version='1.0'?> <!--*-nxml-*-->
-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
-
-<!--
- SPDX-License-Identifier: LGPL-2.1+
--->
+<!-- SPDX-License-Identifier: LGPL-2.1+ -->
<refentry id="systemd.special">
<filename>cryptsetup-pre.target</filename>,
<filename>cryptsetup.target</filename>,
<filename>ctrl-alt-del.target</filename>,
+ <filename>blockdev@.target</filename>,
+ <filename>boot-complete.target</filename>,
<filename>default.target</filename>,
<filename>emergency.target</filename>,
<filename>exit.target</filename>,
<filename>hibernate.target</filename>,
<filename>hybrid-sleep.target</filename>,
<filename>suspend-then-hibernate.target</filename>,
+ <filename>initrd.target</filename>,
<filename>initrd-fs.target</filename>,
<filename>initrd-root-device.target</filename>,
<filename>initrd-root-fs.target</filename>,
<filename>sysinit.target</filename>,
<filename>system-update.target</filename>,
<filename>system-update-pre.target</filename>,
+ <filename>time-set.target</filename>,
<filename>time-sync.target</filename>,
<filename>timers.target</filename>,
<filename>umount.target</filename>,
+ <filename>usb-gadget.target</filename>,
<!-- slices --><filename>-.slice</filename>,
<filename>system.slice</filename>,
<filename>user.slice</filename>,
<citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry>
for details on the targets involved.
</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>boot-complete.target</filename></term>
+ <listitem>
+ <para>This target is intended as generic synchronization point for services that shall determine or act on
+ whether the boot process completed successfully. Order units that are required to succeed for a boot process
+ to be considered successful before this unit, and add a <varname>Requires=</varname> dependency from the
+ target unit to them. Order units that shall only run when the boot process is considered successful after the
+ target unit and pull in the target from it, also with <varname>Requires=</varname>. Note that by default this
+ target unit is not part of the initial boot transaction, but is supposed to be pulled in only if required by
+ units that want to run only on successful boots.</para>
+
+ <para>See
+ <citerefentry><refentrytitle>systemd-boot-check-no-failures.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ for a service that implements a generic system health check and orders itself before
+ <filename>boot-complete.target</filename>.</para>
+ <para>See
+ <citerefentry><refentrytitle>systemd-bless-boot.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ for a service that propagates boot success information to the boot loader, and orders itself after
+ <filename>boot-complete.target</filename>.</para>
</listitem>
</varlistentry>
<varlistentry>
<varlistentry>
<term><filename>default.target</filename></term>
<listitem>
- <para>The default unit systemd starts at bootup. Usually,
- this should be aliased (symlinked) to
- <filename>multi-user.target</filename> or
- <filename>graphical.target</filename>.</para>
+ <para>The default unit systemd starts at bootup. Usually, this should be aliased (symlinked) to
+ <filename>multi-user.target</filename> or <filename>graphical.target</filename>. See
+ <citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry> for
+ more discussion.</para>
- <para>The default unit systemd starts at bootup can be
- overridden with the <varname>systemd.unit=</varname> kernel
- command line option.</para>
+ <para>The default unit systemd starts at bootup can be overridden with the
+ <varname>systemd.unit=</varname> kernel command line option, or more conveniently, with the short
+ names like <varname>single</varname>, <varname>rescue</varname>, <varname>1</varname>,
+ <varname>3</varname>, <varname>5</varname>, …; see
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
</listitem>
</varlistentry>
<varlistentry>
is active as long as the system is running.</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><filename>initrd.target</filename></term>
+ <listitem>
+ <para>This is the default target in the initramfs, similar to <filename>default.target</filename>
+ in the main system. It is used to mount the real root and transition to it. See
+ <citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry> for
+ more discussion.</para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term><filename>initrd-fs.target</filename></term>
<listitem>
dynamically when audio hardware is found.</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><filename>usb-gadget.target</filename></term>
+ <listitem>
+ <para>This target is started automatically as soon as a
+ USB Device Controller becomes available at boot.</para>
+
+ <para>This may be used to pull in usb gadget
+ dynamically when UDC hardware is found.</para>
+ </listitem>
+ </varlistentry>
</variablelist>
</refsect2>
not useful as only unit within a transaction.</para>
<variablelist>
+ <varlistentry>
+ <term><filename>blockdev@.target</filename></term>
+ <listitem><para>This template unit is used to order mount units and other consumers of block
+ devices after services that synthesize these block devices. In particular, this is intended to be
+ used with storage services (such as
+ <citerefentry><refentrytitle>systemd-cryptsetup@.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>)
+ that allocate and manage a virtual block device. Storage services are ordered before an instance of
+ <filename>blockdev@.target</filename>, and the consumer units after it. The ordering is
+ particularly relevant during shutdown, as it ensures that the mount is deactivated first and the
+ service backing the mount later. The <filename>blockdev@.target</filename> instance should be
+ pulled in via a <option>Wants=</option> dependency of the storage daemon and thus generally not be
+ part of any transaction unless a storage daemon is used. The instance name for instances of this
+ template unit must be a properly escaped block device node path, e.g.
+ <filename>blockdev@dev-mapper-foobar.target</filename> for the storage device
+ <filename>/dev/mapper/foobar</filename>.</para></listitem>
+ </varlistentry>
<varlistentry>
<term><filename>cryptsetup-pre.target</filename></term>
<listitem>
the <literal>$portmap</literal> facility.</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><filename>time-set.target</filename></term>
+ <listitem>
+ <para>Services responsible for setting the system clock from
+ a local source (such as a maintained timestamp file or
+ imprecise real-time clock) should pull in this target and
+ order themselves before it. Services where approximate time
+ is desired should be ordered after this unit, but not pull
+ it in. This target does not provide the accuracy guarantees
+ of <filename>time-sync.target</filename>.</para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term><filename>time-sync.target</filename></term>
<listitem>
<title>Special User Units</title>
<para>When systemd runs as a user instance, the following special
- units are available, which have similar definitions as their
+ units are available:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><filename>default.target</filename></term>
+ <listitem>
+ <para>This is the main target of the user session, started by default. Various services that
+ compose the normal user session should be pulled into this target. In this regard,
+ <filename>default.target</filename> is similar to <filename>multi-user.target</filename> in the
+ system instance, but it is a real unit, not an alias.</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+ <para>In addition, the following units are available which have definitions similar to their
system counterparts:
<filename>exit.target</filename>,
- <filename>default.target</filename>,
<filename>shutdown.target</filename>,
<filename>sockets.target</filename>,
<filename>timers.target</filename>,
projects / thirdparty / systemd.git / blobdiff