The Cron Job/Crontab
To have your task run at this frequency, use the following cron:
30 12 */3 * *
This cron command translates to the following (in Human-Readable format):
“Every 3 days at 12:30 pm.”
What is a Cron Job & Crontab?
A cron job is a scheduled task that is typically executed automatically at a predetermined time or interval. Cron jobs are often used to perform routine system maintenance tasks, such as backing up files or databases, deleting temporary files, or sending email notifications.
A crontab is a file containing commands and instructions for the cron daemon to execute.
Every cron job uses five fields. Here is an explanation of what each field does in this cron, which runs “every 3 days at 12:30 pm“:
FUN FACT: Cron is one of the most versatile tools in a Linux administrator’s toolbox..
You might want to set up a crontab or cron job to run every 3 days at 12:30 pm for several reasons, including:
- A daily report is generated and emailed every 3 days
- A backup script runs every 3 days
- A cron job that checks for updates to a software package and installs them if available
Similar Cron Jobs
You might also want to run a crontab:
- every 6 days
- every 3 days
- every 1 day
- every 10 days
- every 4 days
- every 2 days
- every 6 days at 7:00 pm
- every 3 days at 4:30 pm
- every 7 days at 2:00 am
FUN FACT: When configuring a cron job, you can specify the minute, hour, day of the month, month and day of the week when it should run – this gives you a lot of flexibility in terms of when your task will be performed automatically!.
In this article, you learned how to set up a cron job that runs every 3 days at 12:30 pm. Please share this page with friends and colleagues if you find it useful.
If you have any questions, please don’t hesitate to comment below.
If you are looking for cron jobs that run at certain minutes, hours, days, weekdays, or months, or if you are looking for miscellaneous cron jobs, then check out our relevant sections, or visit our cron job cheat sheet for a list of hundreds of popular cron jobs.