Crontab did not fire jobs

UNIX for Advanced & Expert Users
1

Hello,
I have something weird that I need some solution and hope that you can help out there :).

I have crontab entry and it is running everyday. Sometimes, the crontab will just hang/stale where my jobs will not be executed(of course, the user complaint, then only I know). I will need to do: crontab -e and save it to force it back in action.

  1. Currently I am checking my job log file to acertain if the crontab is running or not. Is there anywhere in UNIX which allow me to see if the cron is active/hang/inactive?
  2. If you encountered this situation, how do you handle that in your job?

I need your precious advice. Please help!

Thanks
Ben

2

There are a number of monitoring tools that can query/restart processes. init comes to mind as does BB, Tivoli, OpenView, etc.

The real question is why cron is failing. What is in your system and cron logs?

Also you don't need to run "crontab -e", you can either send a HUP to cron or run its rc script.

3

Thanks mdhmi for your reply.
I am unsure how/why it fails. Do you have any recommendation on how to check.
I am using Sun Solaris.

4

Have you looked in /var/cron/log and /var/adm/messages for clues.

You may also want to run:

 ptree $(pgrep cron)

to get some idea of what is happening when you observe the problem.

5

Well depending on what king of system you are running on, there is a file below /etc that is call cron.allow or cron.deny there you'll list the users that are allowed to run crontabs.

Another experience I've had with crontab is that sometimes cron miss the path of the executable files, try to write it entirely

hope it works