Published: 17.09.2026
A cron job is a task that the server runs by itself at times you choose, such as every night or every fifteen minutes. Every Virtual Hosting plan includes cron jobs, so routine work can run without you opening a terminal or pressing a button. This guide explains how a schedule is written, which tasks people usually automate and which mistakes cause silent failures.
What a cron job does
The cron service reads your list of scheduled tasks and starts each command at the times you set. The task runs even when you are not logged in to the control panel. Cron does not judge the result, so a job can fail every night without any visible sign. This is why every scheduled task needs a log and a regular check.
Reading the schedule
A schedule has five fields separated by spaces: minute, hour, day of the month, month and day of the week. An asterisk means every value in that field. Some common examples:
- The schedule 0 3 * * * runs the job every day at 03:00 in the server's time zone.
- The schedule */15 * * * * runs the job every fifteen minutes.
- The schedule 30 8 * * 1 runs the job every Monday at 08:30.
- The schedule 0 2 1 * * runs the job on the first day of each month at 02:00.
Write the expression down, read it back in plain words and check that the time matches what you intend. In the day-of-week field, 0 means Sunday and 1 means Monday.
Tasks people automate
- WordPress scheduled tasks. WordPress normally runs its own scheduled tasks when a visitor arrives. For a steady schedule, set DISABLE_WP_CRON to true in the configuration file and run wp-cron.php from a cron job at a fixed interval.
- Database exports. Export the database every night into a dedicated folder and put the date in the file name.
- Clean-up. Delete temporary files, cache entries or old log archives that are older than a set number of days.
- Imports and reports. Fetch a product feed, update a table of rates or send a daily summary, if your application supports it.
Set up a job safely
- Run the command once by hand, from the same folder, before you schedule it.
- Use full paths to files and programs, because cron starts with a much smaller environment than your terminal.
- Write the output to a log file, so you can read what happened and see errors.
- Start with a low frequency and increase it only when the job has proven itself.
Common mistakes
- Scheduling a job more often than it needs, which adds load and duplicate work.
- Letting runs overlap, when one run is still working as the next one starts.
- Assuming the server clock matches your local time without checking it.
- Leaving an entry in place after its script was removed, so it fails every time.
- Running without a log, so a silent failure goes unnoticed for weeks.
How to know a job works
Write a short line with the date and the result at the end of each run. Read the log after the first run and once a week afterwards. A backup job needs one more step: restore the latest file into a test copy, because a backup that nobody has ever read is not proof that it works. If you cannot find the cause of a failure, open a support ticket with the log lines and the schedule.
Frequently asked questions
Do cron jobs run when I am logged out? Yes. The schedule runs on the server whether or not you are logged in to the control panel or to a terminal.
Can I run a job every minute? The schedule allows it, but a frequent job adds load. Choose the lowest frequency that still meets your goal.
Where do I set up cron jobs? In your control panel. Cron jobs are included with every Virtual Hosting plan.
