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linuxloggingcron

Details of last ran cron job in Unix-like systems?


I want to get the details of the last run cron job. If the job is interrupted due to some internal problems, I want to re-run the cron job.

Note: I don't have superuser privilege.


Solution

  • You can see the date, time, user and command of previously executed cron jobs using:

    grep CRON /var/log/syslog
    

    This will show all cron jobs. If you only wanted to see jobs run by a certain user, you would use something like this:

    grep CRON.*\(root\) /var/log/syslog
    

    Note that cron logs at the start of a job so you may want to have lengthy jobs keep their own completion logs; if the system went down halfway through a job, it would still be in the log!

    Edit: If you don't have root access, you will have to keep your own job logs. This can be done simply by tacking the following onto the end of your job command:

    && date > /home/user/last_completed
    

    The file /home/user/last_completed would always contain the last date and time the job completed. You would use >> instead of > if you wanted to append completion dates to the file.

    You could also achieve the same by putting your command in a small bash or sh script and have cron execute that file.

    #!/bin/bash
    [command]
    date > /home/user/last_completed
    

    The crontab for this would be:

    * * * * * bash /path/to/script.bash