How to DeBug a Cron Job
1) Check for cron output. Output will generally be sent to the user’s mail account. Type “mail” to see if mail exists from this run. If so, a helpful error message should appear. If not, continue.
2) Check the cron logfile for helpful error messages. This is file is probably /var/log/cron but it may be different on your system.
3) Run the script or command on your command line to see if any helpful error messages appear.
4) Use the “at” command to run the script cron-like immediately e.g., “at -f scriptname now”. Type “mail” and check for output to see of there are any helpful error messages. Type “man at” for more info on “at”.
5) Direct the output of your cronjob to an easily accessible discfile:
- 15 10 * * * /home/cfmc/runment 2> /home/cfmc/mentout
- The “2>” part should allow the inclusion of error messages as well.
6) Also when running multiple command statements in the same crontab line you will want to make sure to surround the crontab with quotes as seen in the example below:
#Start up the CDI and then then Stdysrvr and initializes the dialer
11 04 * * * csh -c “setenv CFMC /cfmc/; setenv CFMCCFG /cfmc/ipcfiles/; /cfmc/go/init_cdi > /home/cfmc/.bin/init_cdi.log”