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- Copyright 2013 Lennart Poettering
- Copyright 2016 Zbigniew Jędrzejewski-Szmek
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<refentry id="systemd.offline-updates">
<refentryinfo>
<title>systemd.offline-updates</title>
<productname>systemd</productname>
-
- <authorgroup>
- <author>
- <contrib>Developer</contrib>
- <firstname>Lennart</firstname>
- <surname>Poettering</surname>
- <email>lennart@poettering.net</email>
- </author>
- </authorgroup>
</refentryinfo>
<refmeta>
<citerefentry><refentrytitle>systemd-system-update-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
checks whether <filename>/system-update</filename> exists. If so, it (temporarily and for
this boot only) redirects (i.e. symlinks) <filename>default.target</filename> to
- <filename>system-update.target</filename>, a special target that is pulls in the base system
+ <filename>system-update.target</filename>, a special target that pulls in the base system
(i.e. <filename>sysinit.target</filename>, so that all file systems are mounted but little
else) and the system update units.</para>
</listitem>
</listitem>
<listitem>
- <para>The update service should declare <varname>DefaultDependencies=false</varname>,
+ <para>The update service should declare <varname>DefaultDependencies=no</varname>,
<varname>Requires=sysinit.target</varname>, <varname>After=sysinit.target</varname>,
+ <varname>After=system-update-pre.target</varname>
and explicitly pull in any other services it requires.</para>
</listitem>
+
+ <listitem>
+ <para>It may be desirable to always run an auxiliary unit when booting
+ into offline-updates mode, which itself does not install updates. To
+ do this create a .service file with
+ <varname>Wants=system-update-pre.target</varname> and
+ <varname>Before=system-update-pre.target</varname> and add a symlink
+ to that file under
+ <filename noindex='true'>/usr/lib/systemd/system-update.target.wants</filename>
+ .</para>
+ </listitem>
</orderedlist>
</refsect1>