rsync cron job for backup not working I'm trying to run a backup from one HDD to another at 10pm everynight on a Mac Pro. I have tested the rsync and it backups just fine outside of the cron table. Here is what I have and it's not running 

* 20 * * * rsync -av /Volumes/HDD1/* /Volumes/HDDbackup/

This is on a Mac Pro that doesn't get turned off nightly
Use 00 22 * * * rsync -av /Volumes/HDD1/* /Volumes/HDDbackup/ (instead of 20 - which is 8 pm!) and it will run - set up with the proper user and proper disk permissions.