nForce RAID question

[CubanCorona]

I had a RAID 1 set running fine. Something happend and the nForce RAID controller stopped recognizing the set.

I re-established the set, but the data on the drives is not identical. The nVidia RAID manager recognizes the set and says its status is "rebuilding." However it has been stuck at 2.67% complete for days.

So I have a few questions. How can I tell which drive has the working copy of the data that is actually being used?

If I want to do a manual rebuild, and it asks me which disk ("select a disk"), do I choose the disk with the working data or the disk with the data that needs to be updated? How do I know which is which?

What if I chose to rebuild the disk with the working data from the data that needs to be updated? What would happen?

 

[Madwand1]

One way to get out of this would be to have a real backup. Add an external drive, duplicate the partition from the RAID 1 array to the backup, test that the backup worked by booting off it, and then wipe the original array & restore/rebuilt it from backup.

"RAID is not a backup".

Short of that, it's risky. From what I recall (see note on backup above, no warranties implied etc.), the nForce "rebuild" operation targets the drive to be re-built. I.e. you select the drive you want to be copied to, and tell it to "re-build it". Again, no warranties on this. I can't guarantee that I'm remembering this correctly, and I can't guarantee that your version/implementation does it the same way as mine. I did this with nForce3 BTW.

Odds are that if the RAID array broke, then it reverted to the first drive in the array as a single drive, so the first drive should have the data. At least if you don't have the OS on the RAID array (and maybe even then), you should in theory be able to break the array, and see both drives as single drives. Then you could use a good directory comparison utility to find the differences.

But you seem to have a deeper problem -- why is the RAID array breaking? Maybe it's time to just break the array for good, and use the second drive as an external backup. However, if they're failing, it'd be better to use something else for the backup.