Greetings, 

 

I was upgrading my server motherboard and CPU and I mistakenly plugged the molex connector the wrong way into one of the drive cages.  Now five of my drives are not working (no spinning, not detected at post by the bios).

 

Three of the lost drives were empty, and I have two parity drives elsewhere in the array.  Is there a way to rebuild the data from two lost drives that had data on them using the parity information?

 

Thanks.

Edited April 5, 20188 yr by Sixkiller0
more info

Unfortunately not.     Because of the way parity works it does not matter if a failed drive has data on it or not as parity works at a lower level than the file systems on the disk.    A drive with no data on it still counts as far as parity is concerned (as even a drive with an empty file system is not all zeroes). As far as unRAID is concerned you have 5 failed drives, not two.

Edited April 5, 20188 yr by itimpi

I thought that was the case.  I was hoping for some Unraid black magic. 

 

Thanks for the reply.

You are not the first person who has done this and you won't be the last. The data on your dead drives is very likely to be ok but simply inaccessible because the power reversal has damaged the electronics boards. It is possible to replace them with boards from donor drives - either temporarily to recover the data, or permanently. Whether this is worthwhile depends on how much you value the data and whether you already have adequate backups. The beauty of unRAID is that you only need to concentrate on the two dead drives that you want to recover.

 

Edited April 5, 20188 yr by John_M
typos

Thanks!  I am doing some research into donor drives right now.  Someone in another thread recommended http://www.donordrives.com.  

 

But like you said, I need to decide if it is worth the $$$.

Just friendly remind, change electronic board shouldn't work becuase you also need change the BIOS chip from old board to new board.

 

13 hours ago, Sixkiller0 said:

one of the drive cages.  Now five of my drives are not working

May be bunning just in the cage, does the drive could recognise out of cage ?

 

13 hours ago, Sixkiller0 said:

Three of the lost drives were empty, and I have two parity drives elsewhere in the array. 

Anyway you still need recover at least 3 drive for rebuild even it is empty.

 

Since you swap the 12v and 5v, usually a drive have TVS diode (5v) and fuse for protection. So in most case, just remove theTVS diode ( if it short ) and check the fuse should get back the drive.

 

Edited April 6, 20188 yr by Benson

8 hours ago, Benson said:

Anyway you still need recover at least 3 drive for rebuild even it is empty.

True, but in his case only 2 drives had data, so cheaper to recover just those two and forget about recovering the empty drives.

 

+1 for donordrives, very economical compared to drive recovery firm like ontrack.

Update: I sent the two drives with data to donordrives, and they were unable to repair them.  I recreated the array with the remaining drives, and restored my movies from my backup server.  So I mostly lost some tv series, most of which I don't watch anyway.  I also lost 5 hard drives, which I'll replace the next time the 8TB externals go on sale at BB.

 

My (expensive) take away from this is to be more careful with power connectors.  All in all it could have been much worse.

24 minutes ago, Sixkiller0 said:

I sent the two drives with data to donordrives, and they were unable to repair them.

Bummer. I've had good luck with them, 3 separate instances, all recovered. Not my data, drives my customers brought in.

 

Did they give you a diagnosis on what would have been necessary for recovery? I assume it burnt out the drive motor or actuator, strange that both were unrepairable though.

One of them was "Controller Failure |##| Firmware Failure."  The other was "Controller Failure |##| Cleanroom Service."  I guess I fried them good.

13 minutes ago, Sixkiller0 said:

One of them was "Controller Failure |##| Firmware Failure."  The other was "Controller Failure |##| Cleanroom Service."  I guess I fried them good.

Ouch.

 

So, are you going to change your handle to Fivekiller0?

Haha!!!