SYSTEMD-CRONTAB-GENERATOR(8)

NAME
systemd-crontab-generator - translate cron schedules in systemd Units

SYNOPSIS
/usr/lib/systemd/system-generators/systemd-crontab-generator output-dir

DESCRIPTION
systemd-crontab-generator is a systemd.generator(7) translating classic cron FILES into native systemd.timer(5)/systemd.service(5) pairs.

It runs automatically
•   during early boot,
•   a second time by cron-after-var.service if /var is a separate mount-point, in order to process user crontabs in /var/spool/cron/crontabs,
•   after each update to /etc/crontab† and /etc/anacrontab†, and
•   when packages add files under /etc/cron.d†
(†: monitored by cron-update.path).

FILES
/etc/crontab
    Administrator's system crontab, see crontab(5).
/etc/cron.d
    System crontabs managed by packages live here.
/etc/anacrontab
    anacrontab(5)
/var/spool/cron/crontabs
    Users' crontabs live here.
/run/systemd/generator
    Automatically generated units go here.
/run/crond.reboot
    If this file exists, @reboot jobs aren't re-generated. Managed automatically.
/var/lib/systemd/timers
    systemd.timer(5)s with the Persistent flag set store their timestamps here.

DIAGNOSTICS
systemctl list-timers shows an overview of current timers and when they'll elapse.

If you see something to the effect of
    /usr/lib/systemd/system-generators/systemd-crontab-generator failed with error code 1.
in the journal, you can run /usr/lib/systemd/system-generators/systemd-crontab-generator /tmp/test for more verbose output.

SEE ALSO
crontab(5), systemd.timer(5), systemd.unit(5), systemd.cron(7)