Originally Posted by
NRG
Can I just point out to all considering this that RAID is not as 'safe as it gets' certainly in RAID 1 or mirrored drive mode.
RAID is not a backup it is a method to increase the mean time to data loss in a storage system.
Whatever RAID you have you still need a separate back up.
Deleting a file, corruption of a file, virus infection or simple user error deleting a folder and its tree on a RAID 1 will mean the very same files get deleted or corrupted on the mirror disk a few milli seconds later! You need a separate backup to protect from data loss.
Maybe not so key for the domestic user but worth understanding is that drives are getting larger and if using 3~4TB+ sized drives consider the rebuild time involved in a RAID system especially a stripped parity RAID 5 or 4 and the risk of a second drive loss. It takes a long time to rebuild a 4TB drive and your data is at risk if another drive should fail during that time. You need a separate back up!
Yes its more expense but if you have invested all that time to rip your CD collection or digitize your favorite LP's and edit them ask yourself would you like to do it all again? You need a separate back up! :D