John, good point about a RAID array of multiple drives not being something that should be counted on as an exclusive means of backup. Some additional reasons:
1)If the RAID controller circuitry fails at some point in the future, and if the same or a similar controller is no longer available, for RAID modes other than RAID 1 (simple mirroring) the data may be unrecoverable even if all of the drives are intact.
2)Although unlikely, it is certainly within the realm of possibility that all of the drives in the array could be simultaneously destroyed or corrupted by the power supply going into an overvoltage condition (although a *good* design will include effective protections against that possibility); by misbehavior of the controller circuitry due to undiscovered design bugs; or by misbehavior of software or firmware due to undiscovered design bugs, crashes, malware infections, etc.
Regards,
-- Al
1)If the RAID controller circuitry fails at some point in the future, and if the same or a similar controller is no longer available, for RAID modes other than RAID 1 (simple mirroring) the data may be unrecoverable even if all of the drives are intact.
2)Although unlikely, it is certainly within the realm of possibility that all of the drives in the array could be simultaneously destroyed or corrupted by the power supply going into an overvoltage condition (although a *good* design will include effective protections against that possibility); by misbehavior of the controller circuitry due to undiscovered design bugs; or by misbehavior of software or firmware due to undiscovered design bugs, crashes, malware infections, etc.
Regards,
-- Al