** Description changed: [Impact] Restarting a timer unit that has already executed at least once causes the associated service to run immediately, regardless of the configured OnCalendar schedule. This results in unintended service executions outside the defined schedule. This issue presents a reliability risk for systems relying on systemd timers for precise, predictable scheduling. [Test Plan] 1. Create a service and a timer. For the OnCalendar, 46:00 means the service will be triggered on the 46th minute of every hour, but for testing purposes, you can adjust ti to a couple minutes ahead of the current time. # timer-test.service [Unit] Description="Test service" - + [Service] ExecStart=/bin/echo triggered Type=oneshot - # timer-test.timer [Unit] Description="Test timer" - + [Timer] OnCalendar=*-*-* *:46:00 - + [Install] WantedBy=timers.target - 2. Enable the timer. # sudo systemctl enable --now timer-test.timer - 3. Let the timer trigger once. This is important because you don't see this behavior if the timer has never ran before. - 4. Restart the timer: # systemctl restart timer-test.timer - - 5. View the service status to see the logged echo command and check the time when the service was triggered. + + 5. View the service status to see the logged echo command and check the + time when the service was triggered. # systemctl status timer-test.service After restarting the timer, the service will run again even when it is not scheduled to run. + [Where problems could occur] + + The potential issue is that this behavior may still occur, meaning + services could continue to be triggered immediately after a timer + restart, outside their defined OnCalendar schedule. [Other Info] The bug has been reported upstream: https://github.com/systemd/systemd/issues/31231 It's been fixed in the commit: https://github.com/systemd/systemd/pull/38868/changes/3fc44a0f68412b649e16f12ff2f97a36c615457d Need to backport this fix to Questing and Noble.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2141296 Title: [00427578] Restarting systemd timer triggers service start off- schedule To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/2141296/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
