Drive Failure

Freefaller

One of the drives in my pool has failed. I'm going to pull it this weekend and stick it in a test rig I have to try and recover some data/see if the disk is gone.

Whats the best way to go about fixing the pool? Just replace the drive with a new one? Not all of my shares are duplicated (the important ones are), my films share for example is too big to duplicate, so I'm sure some data must have been lost somewhere, the only thing is I'm not sure what, as my shares actually seem intact.

Philmatic

I seem to be doing this every-other weekend (I have WD Green drives, seems the newer they are the crappier they are), but I have my process down pat:

1. The absolute first thing you want to do is get a listing of all the files on the hard drive. This is done so if you end up losing the data, you can at least start to re-acquire the lost files.
• Assign the failing drive a drive letter in Disk Managment and then run the following command in a command prompt:
• dir /b /s x:\ >> FailingDriveInventory.txt
• Where x is the drive letter you assigned
  
  
2. Then you want to try to recover what you can, I use robocopy for this since it's built into Windows Vista, 7 and WHS 2011:
• robocopy /E /MOVE /COPY:DAT "x:" "y:\RecoveredFiles" /R:0 /W:0
• X is the failing drive, Y is where you want to put the recovered files
• /R:0 and /W:0 set the wait time between failures and the retry amounts to 0 each so it'll speed up the process. Any file that will not read will result in a CRC error and it'll continue onto the next file quickly.
  
  
3. When this is done, all the saved files will be moved off the drive, and you should only be left with the files that failed, reinventory whatever is left of the drive.
• dir /b /s x:\ >> UnrecoverableFiles.txt
  
  
4. Now that the recovery process is complete, all you need to do is remove the drive from DrivePool and it should being reduplicating the missing segments of the files you had duplication turned on for. And the unduplicated files will just be lost, but you know which ones are missing due to your inventory.
   

Let me know if you need clarification on anything.

Freefaller

The trouble I'm having is that I can't mount the disk at all. Unfortunately didn't get chance to pull the drive this weekend, I will do it tonight and hopefully be able to mount it in my test rig.

Cheers for the advice though - will let you know how I get on.

A question that would be useful to know the answer to is whether the drivepool behaves like the drivepool in WHSv1 where files could be on any disk? Or does it attempt to keep files in the same share close together?

Shane

From what I understand, files written to the pool in a given short time period will tend to be written to the same disk (since normally DP will write to the disk with the most free space at the time), and in a future version it should become possible to have much more control over where files go, but for now it's probably best to presume that any two files could be on any two disks in the pool.

Freefaller

Ok so I guess my next question is I can copy stuff off my damaged disk, great.

How do I get it out of the drivepool? If I right click>remove, I get "Access is denied".

Shane

If the drive is damaged such that it can't be removed from the pool while still present, you can physically disconnect it first before telling DrivePool to remove it from the pool. DrivePool will then (after warning you) skip the normal migration process and drop the missing drive from the pool.