Second disk failure during resync after replacing bad disk
I have a Readynas Pro Business with five disks using X-raid2 Last weekend I noticed that two disks were having trouble. One with ATA errors, the other showed bad sectors. Emailed Netgear. Replacements shipped in. All fine.
Setup is as follows: Disk 1: 1GB (fine) Disk 2: 1GB (ATA errors) Disk 3: 2GB (fine) Disk 4: 2GB (fine) Disk 5: 1GB (bad sectors)
Pulled out disk 2, plugged in the new one. Syncing is currently going on. Now suddenly disk 5 is showing as 'dead'. The array has gone into read-only mode, but syncing continues.
Now the situation is: Disk 1: 1GB (fine) DIsk 2: 1GB (spare, syncing) Disk 3: 2GB (fine) Disk 4: 2GB (fine) Disk 5: 1GB (dead)
My questions: - Did I just lose data? - Should I let resync continue? - Should I plug the 'old' bad disk 2 back in, as it still has my data on it? - How do I mitigate the damage?
Re: Second disk failure during resync after replacing bad di
Netgear managed to help me recover my data after a few phone calls and a day or two of copying disks. Turns out two disks were failing at the same time. While I was replacing one bad disk the other went down, and I ended up with a dead array. Taking the disks out and making a bit-for-bit copy of both bad disks using dd_rescue did the trick. One of the bad disks was recognised and after a lengthy resync I've now got five healthy disks again.
This weekend I've made a complete offsite backup and reset my NAS to dual-redundancy.
Data is now recovered and migrated to dual-redundancy with the important parts mirrored offsite. I got in a bit of reorganising and cleaning out of old files and updated the firmware on a few disks while I was at it.
