Unfortunately RAID 5 (or any other flavor) is not a backup solution. It doesn't account for user error, RAID controller failure and numerous other scenarios.
It seems LavaBit had an interesting product, but this seems like a pretty critical design failure.
It's much harder to delete things from backups though. Lavabit promised that when you deleted a message, it was actually deleted. Redundancy against hardware failure but not against user error, software error, etc. was probably part of their security-convenience tradeoff.
Lavabit also flipped the bit and destroyed everyone's emails (without much complaint, at least that I have read). The goal was security, not availability. If security is the goal it's better to fail hard than fail [possibly] insecurely. POP/IMAP email also backs up itself--you retain a copy on your own machine.
> All critical servers use RAID 5.
Unfortunately RAID 5 (or any other flavor) is not a backup solution. It doesn't account for user error, RAID controller failure and numerous other scenarios.
It seems LavaBit had an interesting product, but this seems like a pretty critical design failure.