How to run cron every 20mins so like this:
00:20, 00:40, 01:20, 01:40 etc all the way but not at :00
What should I put in crontab?
A line like
20,40 * * * * /path/to/job
should trigger the job only whenever the minute part of the time is 20 or 40.
If you are putting this in the system’s crontab, add a username after that last star.
Add following line in crontab
20,40 * * * * sh your_script.sh
*/20 * * * * /path/to/script.sh