systemd-crontab-generator(8) translate cron schedules in systemd Units


/lib/systemd/system-generators/systemd-crontab-generator output_folder


systemd-crontab-generator is a generator that translates the legacy cron files (see FILES) into native systemd units & timers.

It is not meant to be run manually, it is called automatically by systemd.

It is run

during early boot,
a second time by cron-after-var.service, only if /var is a separate mount, in order to process user crontabs in /var/spool/cron/crontabs; if any,
after each manual updates to the cron files, (*)
and when distribution packages add files in /etc/cron.d/. (*)

(*): those are monitored by cron-update.path

systemd-crontab-generator implements the m[blue]generator specificationm[][1].


System crontab, see crontab(5).

Directory for system crontabs provided by packages.

See anacrontab(5).

Directory for users crontabs.

Directory where the generated units are stored.

Flag used to avoid running @reboot jobs again after boot.

Directory where systemd store time stamps needed for the Persistent feature.


With systemd >= 209, you can execute systemctl list-timers to have a overview of timers and know when they will elapse.

If you get errors like
/lib/systemd/system-generators/systemd-crontab-generator failed with error code 1.
in the journal, you can manually run
/lib/systemd/system-generators/systemd-crontab-generator /tmp
to get a more verbose error message.


Konstantin Stepanov <[email protected]> for the generator
Alexandre Detiste <[email protected]> for this man page