mjhjmtu

i need a service to start every minute between 09:15 - 17:15.

Whats the best way to achieve this?

I could make 3 timers, one to start (1) the timer (2) which runs the service every minute and one to stop it (3). but then it wouldn't be robust for reboots in between.

You can create a single timer unit with multiple OnCalendar= settings, which will allow you to specify the exact interval you want.

If you look at the man page for systemd.timer, the OnCalendar= section says:

May be specified more than once.

So use three separate settings for the start, middle and end:

[Timer]
OnCalendar=*-*-* 09:15..59:00
OnCalendar=*-*-* 10..16:*:00
OnCalendar=*-*-* 17:00..15:00

This should trigger the timer every minute between the times of 9:15 to 17:15, inclusive.

To run exactly between desired times you need 3 records in cron

15-59 9 * * * /path/to/task
* 10-16 * * * /path/to/task
0-15 17 * * * /path/to/task

Does it have to be a Systemd timer? You could also create a cronjob for this task. For example like this:

*/1 9-17 * * * /bin/systemctl restart SERVICE

This wouldn't run it exactly between 9:15 and 17:15 o'clock but between 9 o'clock and 17:59. But im not too skilled in creating advanced cronjobs...

Hope this helps.