We have just completed a massive recovery for a large UK corporation. They lost a specialist application server containing over 24 million files, but they knew where to come for help. The system was a RAID 5 that had suffered failures on two of the RAID 5 drives, to make this more complex the file system was further configured in external data blocks which we had to virtually merge together to get to the data.
After repairing both of the failed and imaging/cloning those and the remaining drives, we were able to mount the images and get on with the recovery of the data. Determining the drive order and rotation is straightforward, however determining the additional block sequencing took a little longer than anticipated as it turned out that one of the two failed drives had dropped out some time before the other.
Once this had been identified, it was given to our senior RAID recovery specialist to rebuild the system virtually on one of our specialist Raid recovery systems and get on with the recovery.
Once completed we had a very, VERY happy customer who had got years worth of vital work data back.