Apple Software RAID went down, strategies for pinpointing the bad drive?

[goMac]

I had two drives running in RAID 0, and one of them went down and now the RAID volume is unmountable. I could tell right before it crashed as programs began to have extremely long bouts of unresponsiveness. All the classic signs of drive failure.

I'm fully backed up to Time Machine as of 15 minutes before the last shutdown, so I'm not worried about data. I would like to try to figure out which one of the drives died, so I can put the remaining good one in an external case.

Picking up a replacement pair today. I won't be putting the remaining good drive back into a RAID as it's likely a good way through it's lifespan if it's partner died.

Any good strategies for figuring out which drive is the culprit? (Both SMART statuses are clean.)

 

[cutterman]

If there is nothing in the console log you could try listening closely to the drives as they spin up. Often you can hear a persistent clicking sound if it wont initialize properly.

 

[nanofrog]

If there's no logs (or they don't give a S/N for the bad member), you could perform a format for each member of the set (good one would complete, the bad one most likely won't). The good disk needs this anyway to be used.

On the off chance both will complete a full format, you'd need to get diagnostics software (PC + free application from the drive maker would be the cheapest way vs. diagnostic software that runs on Macs).

Please note, that the free software mentioned won't run on a Mac (low level information isn't passed properly due to firmware issues). Just in case you've never tried this before/didn't know.