Solved What if systemd timer is missed due to system being shut down?

[CaffeineAddict]

I see if cron job is set to run when system is shut down then it will not run:

Job scheduling using crontab, what will happen when computer is shutdown during that time?

I schedule some tasks using crontab. What will happen if my computer is shutdown or turned off during the time when cron was scheduled to do something? Does each missed cron job run after compute...

serverfault.com

But what about systemd timers? is behavior the same or do missed timers run as soon as system is up?

 

[wizardfromoz]

Suggest use anacron?

Cron is your go-to scheduler for always-on systems and offers greater flexibility in terms of time and user-specific jobs. On the other hand, Anacron is the tool you need for systems that aren't always running, ensuring that no scheduled task is ever missed

Wiz

 

[CaffeineAddict]

Suggest use anacron?

Thanks Wiz but I think you missed my question, anacron solution applies to cron jobs only?
But I'm concerned with systemd timers because almost all timers on my system are systemd not cron.

I need to know what happens is systemd timer is missed.

edit:

Suggest use anacron?

Actually thanks for telling, it let me to google out for anacron equivalent for systemd and ended up on this:

CHANGES WITH 212:

* Timer units gained a new Persistent= switch. If enabled,
timers configured this way will save to disk when they have
been last triggered. This information is then used on next
reboot to possible execute overdue timer events, that
could not take place because the system was powered off.
This enables simple anacron-like behaviour for timer units.

systemd/NEWS at ec5249a27adb1ffbcd41f2c771e19c3353819456 · systemd/systemd

The systemd System and Service Manager . Contribute to systemd/systemd development by creating an account on GitHub.

github.com

So unless timer units have this switch set to true the behavior is same as with cron jobs.