The Cron Job/Crontab
To have your task run at this frequency, use the following cron:
30 */5 * * *
This cron command translates to the following (in Human-Readable format):
“Every 5 hours at 30 minutes past the hour.”
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 commonly used to automate system maintenance or administration tasks, such as running backups or sending emails.
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 5 hours at 30 minutes past the hour“:
FUN FACT: The most common way to edit cron jobs is using the crontab command – this stands for “cron table,” and it contains all the information about when your tasks should be executed..
You might want to set up a crontab or cron job to run every 5 hours at 30 minutes past the hour for several reasons, including:
- Perform a daily backup at 5:30am
- Update a remote server with new data every 5 hours
- Check for new messages in a mailbox every 5 hours
- Run a program to generate statistics every 5 hours
Similar Cron Jobs
You might also want to run a crontab:
- every 12 hours
- every 10 hours
- every 11 hours
- every 3 hours
- every 1 hour
- every 6 hours
- every hour between 12:00 am and 8:00 pm
- every 4 hours at 10 minutes past the hour
- every hour between 2:00 am and 4:00 am
FUN FACT: If you want to edit your personal crontab, just type: “crontab -e” at the command prompt..
In this article, you learned how to set up a cron job that runs every 5 hours at 30 minutes past the hour. 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.