Do Raid ) Drives need to be completely empty before they are regrouped?

Question

I have 4 500 GB Seagate esata drives on a Addonics Raid Card that are grouped into 2 1 TB Groups. I would like to utilize them in one large group. Do the drives need to be completely empty or will the Data make it through? I am in the process of perpetually backing up everything but will the data be reasonably safe?

Answer 1

When you regroup the drives, it will essentially reformat the drives, because the RAID striping that exists on the two groups will be reorganized to include all drives across one logical drive, much like when you repartition a single hard drive.  You don't have to clear the drives, but if you want the data, you should back it up first.