Just had a RAID 5 array fail on me in the middle of a backup job

Was working on a client's Dell PowerEdge server last Tuesday, doing a routine backup, and bam - two drives dropped out simultaneously. The whole array went offline, and I could hear the drives clicking like crazy. Ended up having to rebuild it from a cold spare I had sitting in my truck, but lost about 6 hours of data. Anyone else deal with RAID failures that seem to happen at the worst possible moment?

2 comments

2 Comments

harper_owens1mo ago

Yeah I remember reading something about how RAID 5 is basically gambling with large drives now because the rebuild time stresses every other drive in the array. One guy on a server forum said he lost three arrays in two years before he finally switched to RAID 6 or 10. Sounds like those extra read/write loads during your backup might have just pushed those dying drives over the edge.

morgan.joseph1mo ago

You lost two drives at once in a RAID 5" - that's the nightmare scenario everyone warns about but most people think won't happen to them. The timing during a backup job makes me wonder if the extra read/write load actually triggered the second failure by stressing drives that were already on their way out. I've started keeping detailed serial number logs on my spares after noticing that drives from the same manufacturing batch often fail close together.