Originally Posted by
mixture
Please, please do not think RAID (whichever number) is the great saviour. I've seen very expensive RAID5 setups fail.
RAID5 is a recipe for disaster, though at least more robust than RAID0; it's very easy to have one drive fail and then have a second drive fail when you're trying to rebuild the RAID on a new drive. Personally for data I want securely stored I'd either use RAID1 or ZFS RAIDZ, which gives you the space efficiency of RAID5 with far more robust recovery.