A time-based execution daemon.



Make sure you have both cron and anacron installed (anacron is not installed by default on Ubuntu Server).

Simple scheduling

You can now schedule simple tasks by placing script files in:

Scripts must:


To confirm a script is recognised:

sudo run-parts --report --test /etc/cron.hourly # or daily, etc
# lists all recognised scripts

To execute all scripts:

sudo run-parts --report /etc/cron.hourly # or daily, etc
# executes *all* scripts

References: (includes kickoff on other distros)


You can schedule :supervisor tasks (see that page for details).

Complex scheduling

Add crontab files to /etc/cron.d/
See for formatting

0 = Sunday and 7 = Sunday ( )
TODO: find better formatting docs

Further reading


man pages

History behind the default times

Backlinks: supervisor

CC0 / Public domain dedication To the extent possible under law, d3vid seaward has waived all copyright and related or neighboring rights to "cron in Grasmere notebook, including code snippets" (why? how?)