anacron

Run anacron jobs now

$ sudo anacron -n

$ sudo anacron -d

$ anacron -T

$ sudo anacron -f

$ sudo anacron -t [/etc/anacrontab]

anacron [-s] [-f] [-n] [-d] [-t anacrontab] [-T]

anacron is a cron-like job scheduler that doesn't assume the computer is running continuously. It's ideal for laptops and desktop machines that aren't powered on 24/7, ensuring periodic jobs run even if the scheduled time was missed.
Unlike cron, which runs jobs at specific times, anacron runs jobs based on periods (daily, weekly, monthly) and tracks the last run date. If a job's period has elapsed since the last run, it executes the job.

-f

Force execution ignoring timestamps

Run jobs now, ignoring delays

Run in foreground (no daemon)

Serialize job execution (sequential)

Test configuration file syntax only

Use alternate anacrontab file

Use alternate spool directory

Update timestamps only, don't run jobs

/etc/anacrontab

Defines periodic jobs with their period in days, delay in minutes, identifier, and command to execute.

Timestamp files tracking the last execution date of each job.

Runs as root by default; user-level jobs require additional configuration. Job delay settings are randomized to avoid resource spikes. Not suitable for time-critical tasks.

anacron was created by Christian Schwarz and first released in 1998 to address cron's unsuitability for machines that aren't always on. Most modern Linux distributions include it alongside traditional cron.

cron(8), crontab(1), systemd.timer(5)