system namespacing options. One such service is systemd-udevd.service
wher this is now used by default.
+ * A new unit "system-update-pre.target" is added, which defines an
+ optional synchronization point for offline system updates, as
+ implemented by the pre-existing "system-update.target" unit. It
+ allows ordering services before the service that executes the actual
+ update process in a generic way.
+
Contributions from: Adam Duskett, Alan Jenkins, Alessandro Casale,
Alexander Kurtz, Alex Gartrell, Anssi Hannula, Arnaud Rebillout, Brian
J. Murrell, Bruno Vernay, Chris Lesiak, Christian Brauner, Christian
<filename>swap.target</filename>,
<filename>sysinit.target</filename>,
<filename>system-update.target</filename>,
+ <filename>system-update-pre.target</filename>,
<filename>time-sync.target</filename>,
<filename>timers.target</filename>,
<filename>umount.target</filename>,
</varlistentry>
<varlistentry>
<term><filename>system-update.target</filename></term>
+ <term><filename>system-update-pre.target</filename></term>
<term><filename>system-update-cleanup.service</filename></term>
<listitem>
<para>A special target unit that is used for offline system updates.
<citerefentry><refentrytitle>systemd.offline-updates</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
</para>
- <para>Updates should happen before the <filename>system-update.target</filename> is
- reached, and the services which implement them should cause the machine to reboot. As
- a safety measure, if this does not happen, and <filename>/system-update</filename>
- still exists after <filename>system-update.target</filename> is reached,
- <filename>system-update-cleanup.service</filename> will remove this symlink and
- reboot the machine.</para>
+ <para>Updates should happen before the <filename>system-update.target</filename> is reached, and the services
+ which implement them should cause the machine to reboot. The main units executing the update should order
+ themselves after <filename>system-update-pre.target</filename> but not pull it in. Services which want to run
+ during system updates only, but before the actual system update is executed should order themselves before
+ this unit and pull it in. As a safety measure, if this does not happen, and
+ <filename>/system-update</filename> still exists after <filename>system-update.target</filename> is reached,
+ <filename>system-update-cleanup.service</filename> will remove this symlink and reboot the machine.</para>
</listitem>
</varlistentry>
<varlistentry>