Difference between revisions of "Crontab"

Latest revision as of 12:46, 8 June 2014

What does crontab do

Cron is a UNIX daemon that executes programs/scripts on a schedule. Crontab is a configuration file used by the cron daemon that allows users to set up their periodic tasks.

Configuration

You can turn on the cron daemon from the webend, or by running the following command through telnet/ssh:

config_tool -c CROND='ON'
/etc/init.d/S90crond start 

To configure tasks to be executed, you should execute the following commands through telnet/ssh:

crontab -e

Only use the crontab editor to set up our tasks. The crontab syntax is explained here

Common issues

If, for some reason, the crontab is not picked up on system startup, you can do the following:

• create a /conf/S99user-script file
• append the following commands to the end of the file and save it

# force-load the user's crontab in a subshell, in the background
(sleep 120; crontab -u root /conf/root)&

Useful links

• http://www.cyberciti.biz/faq/how-do-i-add-jobs-to-cron-under-linux-or-unix-oses/
• http://forum.wdlxtv.com/viewtopic.php?f=38&t=5079&p=41827#p41827
• http://wiki.wdlxtv.com/Youtube_subscriptions