[Sanddancer]

Repeat after me: RAID is not a backup. It will mitigate certain drive failures, but is not a backup. Period, end of statement. Controllers will forget their info, OSes will eat their partition tables, and will otherwise ruin your data. If you're not backing up your stuff, to a completely separate system, preferably to a completely separate service, you will lose data. Period.

[Udo]

I don't think that's what ashray meant. A backup (as in failover) HD, not an HD that stores backups... Because apparently to add insult to injury, in this case they ignored a failed RAID drive and didn't have backups.