summaryrefslogtreecommitdiff
path: root/man/systemd.offline-updates.xml
diff options
context:
space:
mode:
authorZbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>2016-11-29 01:29:02 -0500
committerZbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>2016-11-29 01:40:34 -0500
commit953bf4604f5ce02d1bd8abb09e82ea80e101c8a3 (patch)
treed9ae2a086fd16fae4da49e5cfe10d09d0db03f85 /man/systemd.offline-updates.xml
parent2b656050b624312a472cc5df6870999745bd8ad5 (diff)
units: add system-update-cleanup.service to guard against offline-update loops
Note: the name is "system-update-cleanup.service" rather than "system-update-done.service", because it should not run normally, and also because there's already "systemd-update-done.service", and having them named so similarly would be confusing. In https://bugzilla.redhat.com/show_bug.cgi?id=1395686 the system repeatedly entered system-update.target on boot. Because of a packaging issue, the tool that created the /system-update symlink could be installed without the service unit that was supposed to perform the upgrade (and remove the symlink). In fact, if there are no units in system-update.target, and /system-update symlink is created, systemd always "hangs" in system-update.target. This is confusing for users, because there's no feedback what is happening, and fixing this requires starting an emergency shell somehow, and also knowing that the symlink must be removed. We should be more resilient in this case, and remove the symlink automatically ourselves, if there are no upgrade service to handle it. This adds a service which is started after system-update.target is reached and the symlink still exists. It nukes the symlink and reboots the machine. It should subsequently boot into the default default.target. This is a more general fix for https://bugzilla.redhat.com/show_bug.cgi?id=1395686 (the packaging issue was already fixed).
Diffstat (limited to 'man/systemd.offline-updates.xml')
-rw-r--r--man/systemd.offline-updates.xml4
1 files changed, 3 insertions, 1 deletions
diff --git a/man/systemd.offline-updates.xml b/man/systemd.offline-updates.xml
index 22aa0354a8..d673cf5db8 100644
--- a/man/systemd.offline-updates.xml
+++ b/man/systemd.offline-updates.xml
@@ -115,7 +115,9 @@
<listitem>
<para>The upgrade scripts should exit only after the update is finished. It is expected
that the service which performs the upgrade will cause the machine to reboot after it
- is done.</para>
+ is done. If the <filename>system-update.target</filename> is successfully reached, i.e.
+ all update services have run, and the <filename>/system-update</filename> symlink still
+ exists, it will be removed and the machine rebooted as a safety measure.</para>
</listitem>
<listitem>