The Cron Job/Crontab
To have your task run at this frequency, use the following cron:
* 21-23 * * *
This cron command translates to the following (in Human-Readable format):
“Every minute between 9:00 pm and 11:00 pm.”
What is a Cron Job & Crontab?
A cron job is a Linux utility used for scheduling the execution of commands or scripts at a specified time and date. Cron is typically used for system maintenance or administration, such as running backups or log rotation.
A crontab is a table or list of commands that are scheduled to run at specified times. The commands in a crontab file (also called a “cron table”) are normally executed by the cron daemon, which runs in the background and executes these commands automatically.
Every cron job uses five fields. Here is an explanation of what each field does in this cron, which runs “every minute between 9:00 pm and 11:00 pm“:
FUN FACT: Cron is typically used for things like system maintenance tasks, running backups etc..
You might want to set up a crontab or cron job to run every minute between 9:00 pm and 11:00 pm for several reasons, including:
- Automatically turning off all lights in the house at 11:00 pm
- Running a backup of all user data on the system at 10:00 pm
- Checking for new emails every minute between 9:00 pm and 11:00 pm
Similar Cron Jobs
You might also want to run a crontab:
- every 4 minutes
- every 15 minutes
- every 19 minutes
- every 23 minutes
- every minute between 6:00 am and 3:00 pm
- every minute between 9:00 am and 10:00 am
FUN FACT: When troubleshooting issues with cron jobs, it can be helpful to run them manually from the command line – this will allow you to see any error messages that might be generated..
In this article, you learned how to set up a cron job that runs every minute between 9:00 pm and 11:00 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.