systemd timers instead of cron

Cron is still around, but for recurring jobs I increasingly use systemd timers: logs in journald, dependencies, and catching up on missed runs after a reboot.

# /etc/systemd/system/backup.timer
[Unit]
Description=Run backup nightly

[Timer]
OnCalendar=*-*-* 02:30:00
Persistent=true
RandomizedDelaySec=15m

[Install]
WantedBy=timers.target

The timer starts a oneshot service with the same name. Persistent=true runs the job at next boot if the machine was off at the scheduled time.

systemctl daemon-reload
systemctl enable --now backup.timer
systemctl list-timers

Check the output with journalctl -u backup.service — much nicer than digging through cron mail.