The Cron Job/Crontab
To have your task run at this frequency, use the following cron:
30 18 */4 * *
This cron command translates to the following (in Human-Readable format):
“Every 4 days at 6:30 pm.”
What is a Cron Job & Crontab?
A cron job is a time-based task that is typically set up to run automatically at regular intervals. For example, a cron job might be used to send out a daily email report or to back up files every night.
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 4 days at 6:30 pm“:
FUN FACT: One common use for cron jobs is to send out email reminders or notifications based on certain events (such as an upcoming deadline)..
You might want to set up a crontab or cron job to run every 4 days at 6:30 pm for several reasons, including:
- To run a system backup every 4 days
- To send out a report to a group of people every 4 days
- To check for updates to a software every 4 days
- To clean up temporary files on a server every 4 days
Similar Cron Jobs
You might also want to run a crontab:
- every 8 days
- every 9 days
- every 5 days
- every 7 days
- every 1 day
- every 1 day at 7:30 am
- every 1 day at 1:00 pm
FUN FACT: If you need to temporarily disable a cron job, you can simply comment out the line in the crontab file that corresponds to that particular task..
In this article, you learned how to set up a cron job that runs every 4 days at 6:30 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.