Data Loss in RAID and RAID data recovery
RAID or Redundant Arrays of independent Disks is a data storage technology that caters to clients who have huge data storage needs. In RAID systems many low cost disks are assembled together to create superior and more capable storage solution. The RAID arrays are usually used as a server but it can also be used as a general system too. The RAID systems are usually robust and they are perfectly reliable for huge data storage needs. But when they start losing data, it can really be a big mess for all concerned with its services. As RAID systems are more complex and their working mechanism too is complicated, the RAID arrays need special attention to recover the data that has lost from the system.
Data loss or failure in RAID system can occur due to various reasons. However, some of the most common reasons for hard disk data loss are the following:
- RAID controller Failure
- RAID array Failure
- Rebuild Failure
- Damaged strip
- Possible damage to the RAID configuration
- Multiple hard drive crash
- Software corruption
- Defects with the MFT mount points
- Virus infection etc
Whatever the reason behind data loss, the RAID failures require immediate intervention to stop the damage that may increasingly engulf the system within a very short span of time, if used without supervision despite data loss. The professional data recovery companies usually take up RAID data recovery cases for a three step recovery technique.
The first step is to check whether all the arrays are working properly. If any of the hard disks are not completely fit, the engineers repair it in the clean rooms until it starts functioning normally. This is a very important procedure to recover the lost data completely. Moreover, as the disks in the systems are interlinked, one cannot think of recovering the lost data without repairing the malfunctioning drive.
In the next step, the engineers prepare sector by sector clones of the hard drives. This ensures that no more data is damaged while trying to recover the lost data from the RAID arrays. The cloning process is performed in a “write protected” mode. This ensures that the data recovery process does not overwrite other files that have been recovered and those that were occupying a particular location before the data loss situation.
The last step is to “destrip” the cloned drives. In this method, all the scattered data that have been recovered and that are scattered over many drives are brought on to a single destination drive. Once this process is completed the media is rebuilt and ready for handing over to the customer again.