Hi-

I am having some trouble with crontab. I have a file called backup.sh in bin and I want to execute that every day of the week. I tried adding the following line to my crontab file in etc.

30 3 * * * root /bin/backup.sh

I know that backup.sh works because I can sudo backup.sh from the terminal and it works. I than tried doing simpler things like:

* * 15 7 * root echo "Write this every minute to the terminal"

That didn't work either. Is there anything I am missing? Does anyone know what's happening?

Thanks.

Instead of adding it to /etc/crontab, do you experience the same problem when you modify the root user's crontab by running 'sudo crontab -e'?

The above crontab syntax is used for "system" cron jobs that can be found in files located in this directory: /etc/cron.d/

To make the backup work in root's user crontab (not system crontab) the above would need to be changed to look like this:

Notice that 'root' is not specified? That's because you put it in root's user crontab (by typing "crontab -e" and entering the line) so ... naturally ... root will be the user running the /bin/backup.sh script.

All user and root specific cron jobs can be found somewhere in here: /var/spool/cron/ (or thereabouts depending on your distribution).

So if you have a user named tony then his cron jobs would be in a file called /var/spool/cron/tony The 'tony' user can edit his own cron by typing 'crontab -e' ... when he saves it it will go to /var/spool/cron/tony

If there is a system controlled crontab it will be here: /etc/cron.d/ ... and a username needs to be specified here in order to tell cron who to run the line as.

There are also system directories for scripts to be stored and executed by cron as the root user. Your backup.sh script could be moved to: /etc/cron.daily/ ... and it will be executed every day by cron as the root user.

Hope this helps.

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