4TB of data still there but not accessible after RAID5 rebuild

Redgie

Redgie

Redgie

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At the start of December a 2TB drive in my Windows 2008R2 server's 6x2TB RAID5 array failed. The monitoring software crashed so I only found out at the start of January. I ordered a new drive and replaced the faulty one.

Here's where I messed up, in MegaRAID, instead of pressing "Rebuild" using the new drive, I first pressed "Mark Online", which I believe fooled the controller into thinking the original drive was working again, and so set about utilising the 2TB of data on the drive (or lack thereof). Quickly I realised my mistake, and so set the drive back to offline, and then started the rebuild. The rebuild was worryingly quick (around 12 hours), but appeared to complete without issue.

Once complete, I opened the array in Windows, only to discover that a series of folders had become inaccessible, and some disappeared altogether. I ran a RAID consistency check and this fixed the inaccessible folders, but one particular folder remains missing, along with its 4TB of contents. The thing is, the drive in Windows still only has the amount free that it had before the rebuild (400GB), so the data is definitely still on the array, I just can't see it.

Over the last week I've ran GetDataBack, and sure enough it has found the folder (and its 4TB of contents), meaning it's still there on the array. The problem however, is two fold:

1. I can't seem to get Windows to see the files, even though they are on the hard drive, it seems like its lost the "link"?
2. If I give up on Windows seeing them, and instead recover them to another drive with a vision to move them back to the array, there will still only be a small amount of free space on the array (400GB), as Windows still won't recognise that the data is "gone"

Any thoughts? Perhaps there's a simple function like checkdisk or some program I can run to enable Windows to re-recognise either the data still on the drive, or the freed up space?

Thanks in advance!

UPDATE: I have now resolved my issue :)! A simple checkdisk made all missing folders return, and took all of 30 seconds. Wish I'd done this sooner. Thank you to those that tried to help, if anybody finds this in future, do a checkdisk :)!
 
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Could I please get this moved to either General or Storage? I posted it here in the hope it would attract the RAID experts, but perhaps I should have put it in one of the others...

Thank you :)
 
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I assume this isn't an option.

Delete the array, re-create it, restore from your backup.

--

If it's data you need, I'd use a recovery tool to extract it onto an external drive.

This may be worth a shot after you know the data is safe..


http://www.freeraidrecovery.com/
 
Bledd, as above, the data has already been successfully recovered, however the original data is still in place (but inaccessible), so there is no means recovering it externally and putting it back in, because I have no way of deleting it :)
 
This is something similar to what we had at work a awhile ago. There were folders and files on one of our mirror RAID boxes that showed the array was full but there were no visible files. we did not want to risk losing it so sent the box to DiskEng Data Recovery http://www.diskeng.com they said that the "MFT records had become out of sync" anyway they fixed those MFT records and all the files were returned to us. Now that just an option. But you may want to try other software that finds the damage and repairs it but bear in mind that you could lose those files.
 
Hmm, a paid option isn't really worth it for the data that's been lost. It's all replaceable, but will take along time (thus my interest in not losing it), but replaceable none the less...

Perhaps it's time to try a chkdsk...
 
I'd suggest you rebuild the array from scratch and restore the data that way - what other "horrors" are lurking ready to bite at any time?
 
Are you sure get data back has actually seen the files?

My advise would be to buy a XTB drive or as many as needed, copy it all off using whatever method and then not to use RAID. RAID is not what you need here, especially as you clearly don't have a backup...
 
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Yes, I can browse the files in GetDataBack as stated above :) RAID is definitely right for me, the data is not valuable and the loss of it is not an issue beyond being an inconvenience. I'm trying to avoid the inconvenience that's all :)
 
Redgie said:
Neither does RAID? This incident occurred because of my mistake not a fault in the technology?
Click to expand...

What difference does it make?

User error or technology error, result is the same.

I can't press one button and cause the 16TB of data on my server to become easily unreadable.

I would humbly suggest that you re-evaluate your need for RAID.
 
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I can fill my car with the wrong fuel and watch the engine fail, does that mean I should re-evaluate my need for it and cycle to work? Honestly, you ask some people for advice fixing something and all they want to do is tell you how you're wrong and should change :p

I have now resolved my issue :)! A simple checkdisk made all missing folders return, and took all of 30 seconds. Wish I'd done this sooner. Thank you to those that tried to help, if anybody finds this in future, do a checkdisk :)!
 
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