Configuring Cron Jobs

A how-to for configuring a cron job.

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TrueNAS allows users to run specific commands or scripts on a regular schedule using cron(8). This can be helpful to run repetitive, mundane tasks.

Create Cron Job

To create a cron job, go to Tasks > Cron Jobs and click ADD. An optional description can be specified to help identify the purpose of the cron job. Next, enter the exact command to be run, or enter the path to the desired script to be run. Don’t forget to specify the shell type if specifying a path to the script file. For example, a script written for sh should be specified as sh /mnt/pool1/helloWorld.sh. Select a user to run the command or script. The user must have the necessary permissions to run it. Next, select a schedule for the script to run on. If a custom schedule is desired, select Custom and fill out the custom scheduler to meet your needs. The custom scheduler can accept standard cron input strings for the Minutes, Hours, and Days. When Hide standard output (stdout) is unset, any standard output is mailed to the user account used to run the command. When Hide Standard Error (stderr) is unset, any error output is mailed to the user account used to run the command. This can be useful to help debug the command or script if an error occurs. Unsetting Enabled only keeps the task from automatically running. You can still save the cron job and run it manually.

To manage existing cron jobs, go to Tasks > Cron Jobs. A task can be ran immediately, edited, or deleted by clicking to expand a cron job in the list.