I have a DS220+ with 2 identical drives, configured as RAID, so just one volume. Everything was working great, but to access the new object-recognition in photos, I added RAM, which caused some corruption and now the volume is read-only and won’t repair itself (even after removing the RAM). So now I’m preparing to do an external backup and rebuild the NAS. But now I’m wondering: If volume issues are more likely than drive issues, should I forget about RAID, create one volume on each drive, and use the second volume as a local backup? Or is RAID still the best first line of defence? (Or is there a way I can do both with two drives?
RAID is not backup. RAID is used for increased capacity, throughput or uptime. (Depending on configuration)
Multiple volumes would likely get corrupted just as much with faulty RAM as RAID would. Besides RAM there’s controller, CPU, power supply and possibly more single points of failure in that NAS, that would destroy both RAID and multiple volumes.
So assuming you have external backup, I’d go with RAID for better uptime as opposed to some custom multi volume pseudo-RAID for the same.