The Cron Job/Crontab
To have your task run at this frequency, use the following cron:
0 21-22 * * *
This cron command translates to the following (in Human-Readable format):
“Every hour between 9:00 pm and 10:00 pm.”
What is a Cron Job & Crontab?
A cron job is a time-based task that is set to run at specific intervals. This can be anything from running a script every hour to backing up a database every day. Cron jobs are typically used for maintenance or automation purposes.
Crontab is a file that contains instructions for the cron daemon. The cron daemon is a program that runs in the background and executes tasks at specified times. The crontab file is used to specify which tasks are to be run and when they are to be run.
Every cron job uses five fields. Here is an explanation of what each field does in this cron, which runs “every hour between 9:00 pm and 10:00 pm“:
FUN FACT: When editing your crontab, it is important to use a text editor that supports Unix-style line endings (LF), as opposed to Windows-style line endings (CRLF)..
You might want to set up a crontab or cron job to run every hour between 9:00 pm and 10:00 pm for several reasons, including:
- Scheduling a backup to run every night at 9:00 pm
- Sending a daily report email every night at 10:00 pm
- Running a script to update a database every night at 9:00 pm
Similar Cron Jobs
You might also want to run a crontab:
- every 11 hours
- every 1 hour
- every 12 hours
- every 7 hours
- every 6 hours
- every 4 hours
- every hour between 12:00 am and 2:00 pm
- every 4 hours at 20 minutes past the hour
- every hour between 2:00 pm and 5:00 pm
FUN FACT: Cron jobs are often used to perform regular maintenance tasks, such as running backups or sending out reports..
In this article, you learned how to set up a cron job that runs every hour between 9:00 pm and 10:00 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.