Cron → systemd Timer

Convert a cron expression into a systemd OnCalendar timer unit.

Cron expression

At 03:00 AM, Monday through Friday

OnCalendar

Mon *-*-* 03:00:00

Verify with systemd-analyze calendar "Mon *-*-* 03:00:00".

myjob.timer

[Unit]
Description=Run my job (At 03:00 AM, Monday through Friday)

[Timer]
OnCalendar=Mon *-*-* 03:00:00
Persistent=true

[Install]
WantedBy=timers.target