RAID5 Array dropped two hard drives, all physical faults, how to recover data

1. Server Data Recovery failure description

Today, the data recovery of the server failure situation for the hard disk offline, the fault server is a group of hard disks consisting of a set of RAID5 disk array, due to the server's hard disk dropped the server crashed, the administrator check the server found that both hard disks have physical failure, To recover data you must first fix the physical failure of the dropped hard drive.

2. Hard Disk physical failure repair

Server Data Recovery Engineer First will drop the two hard drive to detect, hard drive after the head can not seek, separate PCB clean HDA components after again try to power still can not seek, only the failure of the hard drive to physical repair (no photo in the clean room, no picture).

3. Reorganizing the RAID-5 disk array

The underlying data for all the hard disks in the server was observed to show that the 0 sectors showed a "0x01c2h" (the type of the partition represented here, "05", which represents an extended partition.) Therefore, the MBR partition structure status is not normal. In addition to the 8th hard drive is a normal MBR partition, its 0x01c6 value represents the next sector pointing to the GPT's head.

Figure 1
Number 7th hard drive the value at 0X01C6 represents the next sector. But the next sector is obviously not the GPT's head.

Figure 2
So the data recovery engineer initially inferred that 8th and 7th were the first and last hard disks in the array, with the GPT partition sector starting at 172032 sectors, so it was initially determined that the starting sector of the LUN was 172032 sectors. Data Recovery Engineer Analysis of the server RAID array results in a stripe size of 1024 sectors. The size of a stripe is divided by 1024 sectors, and 7 disks jump to the same record 283123.
When the 7 plates are positioned in the same position, the direction of the calibration area can be judged by contrast, and then the direction of the whole RAID-5 is judged. It has been determined that the 8th is the first plate, the number 8th set in the first position, to determine the RAID-5 for the left direction, the order of 8,2,3,4,1,7,5.
The engineer initially determined that the starting sector of the LUN is 172032 sectors. Use data Recovery tool to jump to 172032 sectors to observe the use of the hard disk, normally this sector belongs to the strip of the 5th plate should be the check area, but the actual situation shows that the check area is 8th, according to the rules of the raid left, the check area of the 5th plate should be at 172032-1024 = 171008 sectors, that is, the previous stripe. Jump to 171008 sectors and find the check area is number 5th. You can therefore determine that the starting sector of the LUN is 171008 sectors.
Use the Data Recovery tool to add in the identified sequence reorganization raid. Select Raid-5,stripe size 512KB, left async.

Figure 3
Click Build to Reorganize. After the group is good, since the data starts from the 1024*8=8192 sector, if the professional recovery tool does not jump to this sector, then a raid must be set up with a file and a build reorganization operation. RAID start sector (start sectors) Select 8192, this file can be arbitrarily selected starting sector and size (Count sectors) for the restructured RAID5 disk array.

Figure 4

4. Server Data Recovery Results

RAID-5 disk array rebuild is completed through customer verification, validation passed, server data recovery succeeded.

RAID5 Array dropped two hard drives, all physical faults, how to recover data