Our storage engineer recently noticed a bad drive on a server. It is the OS drive, and is RAID 1. It is used in a major clinical system.

As he pulled the drive to replace it, the mirrored drive failed.

He was somewhat displeased.

He had a deadline for another project that day. What should have been a 15 minute swap at most, took the entire day, and he was still unable to recover what he needed.

Oh, the other project, deadline missed.