systemd timer
also: systemd-timer, timer unit
A systemd unit file that triggers actions at specified times or intervals, replacing traditional cron jobs with a modern, integrated scheduling system.
A systemd timer is a scheduling mechanism defined in a .timer unit file that instructs systemd to run associated services at specific times or after certain events. Timers work in pairs: a .timer unit (which defines when to run) and a corresponding .service unit (which defines what to run).
Timers offer advantages over cron: they integrate with systemd's logging, dependency management, and service supervision; they can trigger after boot delays or system uptime periods, not just calendar times; and they're easier to manage with standard systemd commands like systemctl.
Example: A timer file /etc/systemd/system/backup.timer might contain OnCalendar=daily and Unit=backup.service to run a backup every day. Check timer status with systemctl list-timers or systemctl status backup.timer.