Okay, here is what I'm looking at doing. I have 3 HDD in my server. Right now only 1 is in use for cPanel. What I want to do is setup 2 of the drives in a RAID 1 format then the third as a drive dedicated to cPanel backups. At this moment I have the server up and running and I have a Clonezilla image that cannot be restored on fake raid.

How can I copy EVERYTHING from HDD 1 to HDD 3 so I can install HDD 1+2 in RAID1 then copy HDD 3 contents back to 1 and 2 root partition? I know rsync will work but I have no idea on how to use it really or where to even begin for this.