RAID Data Recovery and Physical Damage

One of our best Toronto data recovery partners recently had a RAID data recovery case involving eight hard disk drives configured in a RAID 5 setup. As you may know, RAID 5 allows the failure of any 1 hard drive and can be rebuilt with no data loss. But unfortunately in this RAID data recovery situation, there were two defective hard drives.  Further investigation revealed that one one of the hard drives had actually failed 5 months ago and the stale data residing on it was of no value to the client. This left our data recovery partner with all their hopes pinned on the one remaining defective disc drive which had apparently just failed and was the ultimate reason for their RAID failure.

When they contacted Memofix later that morning, we asked them if there were any loud clicking or other unusual noises coming from the hard disk drive. They said no, but they noted that the hard drive model was not being reported properly by the SCSI BIOS at boot up. The model was displayed properly, BUT the capacity was indicated as 0 bytes!

After conferring with a few of our RAID data recovery techs we advised the client that the problem was most likely a corrupted module in the hard drive’s “system area” and we suggested we could fix it very easily. The “system area” is a storage area on the hard drive reserved by the drive itself for storing unique settings required by the hard drive to function. If a hard drive can’t read some of the modules, it often reports a zero byte size which prevents any access to the stored data.

As we are located in the Toronto area, the partner packaged up the defective hard drive and brought it immediately to Memofix for further analysis. When we first hooked up the drive, there was a very light, almost indecipherable ticking noise. It did not sound serious and in fact our data recovery experts  still believed the problem was related to a corrupted system area. However our attempts to repair the module were unsuccessful as the hard drive could not write back the changes we made. It appeared we had an issue with the hard drive’s head assembly that would need to be fixed first.  So we opened up the hard drive under class 100 conditions in our Toronto data recovery lab to get a better look. And boy did we get a better look … see the picture we took below. :-(  Notice the heavily crashed area where the smooth platter surface has been roughed up severely as well as an additional ring of damaged at the inner hub of the platter.

There will be no data recoverable from this crashed hard drive! It just goes to show you that even the best data recovery specialists can be fooled as it’s not always possible to hear severe damage with your ear.

By the way, even though this 8 drive RAID array had two bad hard drives, Memofix was still able to rebuild the RAID  with the one stripe being bad throughout the RAID. This results in the recovery of 5 good chunks of data , followed by 1 bad chunk of data through out the volume.  The RAID data recovery results may not be exactly stellar but the client was able to regain many smaller document type files.

raid recovery toronto

badly crashed SAS or Serial Attached SCSI hard drive

SAS SCSI Drive involved in a terrible crash

© 2012, David Foster. All rights reserved.

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