13/08/2026
RAID 1 is supposed to survive one drive failing... so why did the whole array disappear?
That's what one client faced with their dual-bay Toshiba HDEXR01ZNA51 setup. One drive failed, but instead of the system falling back cleanly to the healthy mirror, the ENTIRE array became inaccessible.
Turns out a failing drive doesn't always fail cleanly. Drive 2 was still "talking" to the controller just enough to block the array from mounting on the healthy Drive 1.
Recovery specialist image Drive 1 (the intact mirror) independently, and verify the data straight from that image. Since everything the client needed was already there, Drive 2 was set aside. No need to touch it, no extra recovery cost.
Lesson: RAID 1 isn't automatically "safe" just because one drive is healthy. If your array goes offline, isolate the drives and let a professional check each one separately, you might save on the bill too.
Full case study: link in comments