OPERATING SYSTEM RELOAD
REBUILD RAID DRIVES
RUNNING THE CHECKDISK UTILITY
RECONFIGURE THE RAID ARRAY
USING DATA RECOVERY SOFTWARE
REINITIALIZE RAID ARRAY
REFORMAT DRIVES IN THE ARRAY

RAID data recovery is an extremely complex type of recovery
that requires much experience and expertise with how RAID
arrays work.  If you have a RAID failure, it is best if you do not
try to recover the RAID yourself using "quick fix" techniques or
"off-the-shelf" data recovery software.  Contact a data recovery company as quickly as possible.  These companies have the capability to recover RAID arrays with advanced recovery tools
and techniques required to ensure a successful recovery.

The success of RAID recovery depends on the cause of RAID
failure, the configuration of the RAID array, and whether or
not the user has made attempts to recover the RAID.  Such
attempts can cause permanent data loss!

By using caution and the tips above, you can be on the road to
a successful recovery of your RAID array.

The reality: RAID fails

In reality and to the surprise of most, RAID could fail and often fail. See some typical scenario below :

When one hard disk fails, very often, there is no hot standby. As a result, the raid array is running on degraded mode. While waiting for the replacement drive which may take a day or two, the likelihood of next drive failure disabling the raid volume is very high. It is reasonable to assume that all the drives in the array are from the same batch and subject to equal amount of working stress. So if one disk fails, the other is also near imminent failure and it often does.

Most raid server has a single controller. Its failure will result in catastrophic single point of failure.

Frequently, due to power surge, the controller or a number of disk elements could fail resulting in total loss of data. It is also found that a power surge may corrupt the RAID configuration setting of NVRAM in the controller card.

It is also commonly found that while replacing a faulty drive in an attempt to rebuild the raid volume to healthy state, wrong procedures are performed resulting in wrong or partial rebuild, or complete system breakdown upon completion of rebuild.

Not to forget that a RAID configuration with fault tolerance at best only intends to protect the physical failure, but not logical corruption such as system corruption, virus infection, or inadvertent deletion.

Types Of RAID failures

To summarize, RAID server often fails as a result of the following situations and frequently, a combination of them :

• Malfunctioned Controller
• Raid rebuild error or volume reconstruction problem
• Missing RAID partition
• Multiple disk failure in off-line state resulting in loss of RAID volume
• Wrong replacement of good disk element belonging to a working raid volume
• Power Surge
• Data Deletion or reformat
• Virus Attack
• Loss of RAID configuration settings or system registry
• Inadvertent reconfiguration of RAID volume
• Loss of RAID disk access after system or application upgrade