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Asked: 2024-09-23T17:26:27+05:30 In: ,

Where can I find the log file for cron jobs on my Ubuntu system?

I’ve been having a bit of a rough time figuring out where to find log files for cron jobs on my Ubuntu system. I set up a couple of automated tasks that are supposed to run at certain intervals, but I’m not seeing the results I expect. It’s been a bit frustrating, honestly!

I’m pretty new to Linux, and even though I’ve read a few guides, I feel like I’m still missing something. From what I gather, cron is supposed to run these jobs in the background, but there doesn’t seem to be a straightforward way for me to see if they are actually running or if there are any issues with them. I’ve checked the usual places, like var/log/syslog, but I’m only getting a bunch of unrelated spam from other processes, and it’s hard to sift through all that noise to find what I need.

I’m wondering if there are specific log files dedicated just for cron jobs. Do they have their own logs where I can see outputs and error messages? I’d love to get my hands on that because right now, I feel like I’m in the dark.

Also, if my cron jobs are failing silently, is there a way to set them up to send me an email notification or log the output to a specific file? I heard you can redirect stdout and stderr to a log file, but I’m not sure what the best practices are for doing that or if that’s the most efficient method.

If anyone here has been through this before and can share their insights or tips, I would really appreciate it! What do you guys typically do to monitor your cron jobs? Any recommendations on tools or commands that could help level up my cron game? I’d love to hear your experiences or any best practices that might help make my life easier while automating tasks on Ubuntu! Thanks in advance!

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    2 Answers


    1. It sounds like you’re having a tough time with cron jobs! No worries, that’s totally normal when you’re just getting started with Linux.

      First off, you might want to check the /var/log/cron.log file. This is where you can usually find entries that cron adds when it runs your jobs. However, if it’s not there, you might have to enable cron logging by editing the /etc/rsyslog.conf file. Look for a line like this:

      cron.* /var/log/cron.log

      Uncomment it (remove the # at the beginning) if it’s commented out, and then restart rsyslog with:

      sudo service rsyslog restart

      After that, you should start seeing cron activity recorded in /var/log/cron.log. Pretty handy, right?

      If your jobs are failing and you want to avoid the silent treatment, you can definitely redirect the output and errors to a log file. In your cron job, you can do something like this:

      * * * * * /path/to/your/script.sh >> /path/to/your/logfile.log 2>&1

      This way, stdout (the regular output) gets sent to logfile.log, and stderr (error messages) will go there too. Just don’t forget to check that log file after the job runs!

      And if you want email notifications, you can set up your cron jobs to send output via email. Just make sure you have an email system set up on your machine (like postfix or ssmtp). Then, just add your email at the top of the crontab like this:

      MAILTO="your.email@example.com"

      So every time a job runs, you’ll get an email with the output!

      For monitoring cron jobs, tools like cronitor or healthchecks.io can also help. They monitor your URL endpoints and alert you if the jobs fail to run.

      Hope this helps clear things up a bit! Good luck with your cron job adventures!




    2. Cron Job Log Files on Ubuntu

      In Ubuntu, cron jobs typically log their output to the system log file located at /var/log/syslog. However, the output can be difficult to sift through due to the volume of messages logged by other system processes. To simplify monitoring your cron jobs, you can allocate a dedicated log file for their output. This is done by redirecting both standard output and standard error in your crontab file. For example, you could modify your cron job entry as follows: * * * * * /path/to/your/script.sh >> /var/log/your_cron.log 2>&1. This command appends both the output and any error messages from the script to /var/log/your_cron.log, allowing you to review the execution results in one place.

      Additionally, to receive email notifications for cron job outputs or errors, you can set the MAILTO variable in your crontab. For instance, add MAILTO="your_email@example.com" at the top of your crontab file. This way, when a cron job generates output, it will be emailed to you, ensuring you’re promptly notified of any issues or results. To check your current cron jobs and their respective configurations, you can use the command crontab -l. Using these techniques will help you efficiently monitor your cron jobs and troubleshoot any potential issues you encounter while automating tasks on your Ubuntu system.


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