Someone asked me a question about RAID recovery options for an array they were going to set up. My advice was :
Use Raid 6, hot swap drives, SMART monitoring and ext4 format. Personally I don’t like raid 0 as it is a helluva job to recover (Happened twice to me). Yes, there is a speed advantage but speed is rarely needed for storage (For the OS and programs, mirror two ssd’s and back them up constantly).
I prefer mirroring drive to drive as you can recover a ‘standard’ drive more easily on it’s own, outside the array. I understand the speed advantage, but would use ssds (for a small array) or 64mb cache sata 6 5400rpm Western Digital Red drives. (Reds are best for enterprise work. Blues / Eco spin down frequently so fail early, Greens are ‘domestic’).
Faster spin speeds fail faster and are more delicate IMHO. I’ve never had a good run with Seagates. Basically, they are the only manufacturers in the game and relabel their products for others. Format? Ext4 (ZFS is better, though more exotic, but I doubt you would find a recovery program, THOUGH – see below). ZFS wil require you to become a master. Personally – few people use it.
Overall, I would go for hot swap mirrored drives (with a hot swap spare, making 3 drives – 2 in use, one on standby, mounted and ready to go) and just bypass the whole recovery issue. It will take up to 5 days to read a 4tb drive, then mark the files to recover, then recover them (another 5 days). Simply not practical and useless to the customer “Sorry, it’ll be 2-3 weeks to recover your data”.
I think recovery is a redundant concept as the drives are just too big these days. If you must: Recuva, Easus Paragon, Stellar Phoenix. Quick PS. The Seagate ‘recovery’ service they offer – Useless. It HAS to be recoverable with THEIR software. They couldn’t recover one drive but the guy tried Paragon and got it all but wasn’t allowed to use it to recover the files because the Seagate software is a franchise and you have to use the Seagate software on Seagate drives to get paid.