Am Di, 28. Sep 2021, um 03:43, schrieb JH:

perhaps use
OnCalendar=*-*-* *:*:00

No, the same result, completely bewildered why the timer does not work
in Yocto Linux

Is the timer unit shadowed by some other timer?

Mind that units can live in
* `/lib/systemd/system/`,
* `/etc/systemd/system/`,
* `/run/systemd/system/`
and there's a priority.

Check here: https://www.freedesktop.org/software/systemd/man/systemd.unit.html

Didn't check, but I guess when you `systemctl status your.timer`, it shows the unit in effect. At least with service unit it does. `systemctl cat your.timer` should do this as well.

Regards, Manuel