Run Cron job every N minutes plus offset

by

To run a task every 20 minutes starting at 5 past the hour, try this:

 5-59/20 * * * *

Explanation

An * in the minute field is the same as 0-59/1 where 0-59 is the range and 1 is the step. The command will run at the first minute in the range (0), then at all successive minutes that are distant from the first by step (1), until the last (59).

Which is why */20 * * * * will run at 0 minutes, 20 minutes after, and 40 minutes after — which is the same as every 20 minutes. However, */25 * * * * will run at 0 minutes, 25 minutes after, and 50 minutes after — which is not the same as every 25 minutes. That’s why it’s usually desirable to use a step value in the minute field that divides evenly into 60.

So to offset the start time, specify the range explicitly and set the first value to the amount of the offset.

Examples

5-59/20 * * * * will run at 5 minutes after, 25 minutes after, and 45 minutes after.

10-59/25 * * * * will run at 10 minutes after and 35 minutes after.

1-59/2 * * * * will run every odd minute.

More Related Contents:

  1. Running a cron job at 11:00 every day? [closed]
  2. how to set cronjob for 2 days? [closed]
  3. How can I set cron to run certain commands every one and a half hours?
  4. Cron job every three days
  5. Run CRON job everyday at specific time
  6. Variables in crontab?
  7. How to do a cron job every 72 minutes
  8. Running Cron Tasks on Heroku
  9. Running a cron job at 2:30 AM everyday
  10. CronJob not running
  11. Setting up a cron job in Windows
  12. How to simulate the environment cron executes a script with?
  13. How to create a cron job using Bash automatically without the interactive editor?
  14. How to instruct cron to execute a job every second week?
  15. I need a Nodejs scheduler that allows for tasks at different intervals [closed]
  16. How can I programmatically create a new cron job?
  17. How to send emails via cron job usng PHP mysql
  18. Running a bash script from a cronjob fails with “No such file or directory”
  19. How do I create a crontab through a script
  20. How to conditionally enable or disable scheduled jobs in Spring?
  21. Relative path not working in cron PHP script
  22. Running a cron job on Linux every six hours
  23. Using WGET to run a cronjob PHP
  24. Run a PHP script every second using CLI
  25. git push via cron
  26. How can I set cron job through PHP script
  27. How to schedule a function to run every hour on Flask?
  28. How to prevent the cron job execution, if it is already running
  29. How to set up a cron job to run an executable every hour?
  30. Apache Airflow scheduler does not trigger DAG at schedule time

Leave a Comment