Data recovery from a RAID 0 disk array requires an understanding of RAID architecture. Fundamentally, a RAID array is an aggregation of hard disks which work as a single unit to the computer they are attached to.

The individual RAID disks do not appear as separate disks but as a single, cohesive logical disk volume. RAID 0, or striped array disks are a configuration of RAID disks which spread out data across multiple disks. Failures on a RAID 0 disks are not easily fixed because of the lack of fault tolerance mechanisms but it is possible to recover data from them.

Understanding the RAID Environment and Causes of Failure

RAID, or a Redundant Array of Inexpensive Disks are configured into several RAID levels of implementation. Numbered from RAID 0 to RAID 5, each raid type offers different levels of performance, security, fault tolerance and data protection.

RAID requires high-speed disks and is used for email servers, messaging servers, While RAID 0 provides the highest performance, it also provides the lowest data security and data lost from these disk arrays is significantly harder to retrieve than from a standard IDE volume. There are several causes of RAID 0 failure. Some of them include:

•  Disk Damage – The failure of any single physical disk or multiple disks in a RAID 0 array may cause disk failure. This failure typically occurs if the disk is physically damaged.

• Extraction – RAID disks are placed in an order for data extraction, if the extraction order is changed or corrupted, the array may suffer data loss.

• Controller Failure – RAID arrays may fail if there is a single controller failure. Failure of the controller card may cause data loss.

• Configuration Settings Failure – The loss or corruption of RAID configuration settings or entries in the system registry may cause the array to fail.

• Incorrect or Missing Partitions – Incorrectly partitioning or inadvertent partitioning errors may cause a RAID volume to lose data.

Other factors such as virus attacks, inadvertent deletion and power fluctuations also cause data loss from a RAID 0 array.

Features of RAID 0 Recovery Options

RAID 0 disks are also known as data striping arrays which spread or distribute data across the disks in the array. Since this type of array does not provide for redundancy, data once damaged or lost may be impossible to recover. However, the RAID configuration and data may be retrieved in cases where only the Master Boot Record (MBR) is corrupted, large parts of the file or data lost is clustered on a few disks or when mirror files may be used for reconstruction of the data. It may be even possible to recover data from disks which have not been subjected to a low-level format. Several recovery software applications possess the capability to perform the core analysis of a RAID failure:

• Identify the block size on the disk, typically as multiple of the sector size of the disk.
• Determine Mean Time To Failure (MTTF) and Mean Time Between Failures (MTBF)
• Isolate the damaged data and identify retrievable data and potential unrecoverable data
• Complete disk array diagnostics

Recovery from a RAID 0 Array

When a failed RAID 0 array is sent to specialists for recovery, the first step is to analyze the array and the physical disks themselves. If all the physical disks are intact and relatively free from damage, the probability of complete data restoration increases significantly.

The primary task that follows is to determine the integrity of the RAID controller software and the MBR. Depending on whether the array being analyzed is a hardware RAID or software RAID configuration, varied software and methods of data recovery may be chosen. The most important step in the recovery process is to make clone drives which are exact copies of the data on the member disks.

Once the data from these physical drives is cloned, various tools such as ReclaiMe Free RAID Recovery, DiskInternals Raid Recovery or R-Studio may be used to aggregate, analyze and rebuild data from a single location. These software packages not only perform the analysis, diagnostics and recovery probability determination but use their patented algorithms to read and identify blocks of data, aggregate them and rebuild the files and folders from the striped disks. In the event o physical damage to a disk, specialists in data recovery will isolate the disk and attempt to recover data from physically damaged sectors or surrounding sectors in a specially created clean environment. While the success of this operation may depend on the extent of damage to the disk, data has been recovered from disks with fire, impact and magnetic damage.

Recovering Unrecoverable Data

RAID 0 arrays are typically used on gaming servers and client systems, on email, messaging and news servers for their high performance but their lack of fault tolerance makes the data on this type of RAID vulnerable to deletion and data loss. The use of the right software and recovery techniques go beyond traditional or do-it-yourself data recovery techniques.