The Cron Job/Crontab
To have your task run at this frequency, use the following cron:
30 23 */3 * *
This cron command translates to the following (in Human-Readable format):
“Every 3 days at 11:30 pm.”
What is a Cron Job & Crontab?
A cron job is a task that is scheduled to run at a specific time or interval. Cron jobs are typically used for maintenance or administrative tasks, such as backing up data or updating software.
To create or edit a cron job, users must first open the crontab file using a text editor. The crontab file contains instructions for the cron daemon, which is the program that actually executes the commands specified in the file. Each line in the crontab file represents a single task or command.
Every cron job uses five fields. Here is an explanation of what each field does in this cron, which runs “every 3 days at 11:30 pm“:
FUN FACT: If a cron job is not properly configured, it might never execute – so make sure you double-check your settings before setting one up!.
You might want to set up a crontab or cron job to run every 3 days at 11:30 pm for several reasons, including:
- Run a backup of all user data every 3 days
- Delete all temporary files that are more than 3 days old
- Send out a reminder email to users who have not logged in for more than 3 days
Similar Cron Jobs
You might also want to run a crontab:
- every 9 days
- every 5 days
- every 7 days
- every 2 days
- every 8 days
- every 4 days
- every 1 day at 9:30 pm
- every 7 days at 5:00 am
- every 3 days at 1:30 am
FUN FACT: Cron is one of the most versatile tools in a Linux administrator’s toolbox..
In this article, you learned how to set up a cron job that runs every 3 days at 11:30 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.