How can I set cron to run certain commands every one and a half hours?

Question

How can I set cron to run certain commands every one and a half hours?

Answer 1

*/10 * * * * root perl -e 'exit(time()%(90*60)>60)' && command

90 — it is one and a half hour in minutes

"> 60" — I give to cron ability to delay the start of script during a minute

Also with help of this hack you can set any period with a minute resolution

For example start the script every 71 minutes

* * * * * root perl -e 'exit(time()%(71*60)>60)' && command