Cron » History » Version 3

« Previous - Version 3/5 (diff) - Next » - Current version
Robert Hatcher, 12/04/2019 09:58 AM



cron is a software utility used to execute recurring jobs at specified time. For example the nightly build (development) is downloaded onto CVMFS every night using a cronjob. Scheduling of cronjobs is done in the cron table (crontab). To simply view the current file do

$ crontab -l
To edit it do
$ crontab -e 

This will open up the crontab in vi (I know, take a deep breath -- <esc> :q! <ret> to close without saving changes ;) or define the shell variables EDITOR and VISUAL to your favorite editor e.g. "emacs" before issuing this command ) . It doesn't matter what directory you run the crontab command from - there is one crontab per user per node.

A copy of some of the important crontabs can be found at SRT_NOVA/scripts/crontabs - this should be kept updated to reflect the current state of the crontabs which are being run.

Notable Examples


This crontab downloads development from Jenkins every night. For a period of time the nightly builds were taking longer than usual so the trigger time of this job was pushed back to ensure Jenkins had finished building first.


The doxygen is generated every night here.