Cheatsheet Pages / systemd Cheatsheet
How to test a systemd calendar expression before you ship it — systemd-analyze calendar
Your OnCalendar expression looks right — this shows the normalized form and the actual next elapse before you rely on it.
Most management commands need sudo, and systemctl only works on a system actually booted with systemd — inside containers it fails with “System has not been booted with systemd as init system”. Every command was checked against systemd 255, and the example units pass systemd-analyze verify.
systemd-analyze calendar "Mon *-*-* 03:00"
# Original form: Mon *-*-* 03:00
# Normalized form: Mon *-*-* 03:00:00
# Next elapse: Mon 2026-10-26 03:00:00 UTC (example output — the date moves with the day you run it)
systemd-analyze calendar daily # → Normalized form: *-*-* 00:00:00, plus its next elapse