RAID data recovery:
Data Recovery AID offers data recovery services on complex RAID, SAN and NAS systems. RAID ''Redundant Array of Inexpensive Disks", was designed to increase the reliability of data storage, but often lulls the user into a false sense of security. DRA can quickly and easily restore deleted data from an array and repair data files, such as Exchange information and SQL databases, that may have corrupted due to drive sector errors or controller card mishaps. Should hardware failures on more than one drive occur simultaneously due to power surge, mechanical failure, or controller card failure the logical volumes will be lost along with the data. Data Recovery AID can help! We also understand the time sensitive nature of most RAID data losses and have an emergency unit standing by to offer immediate and free phone assistance.

In many cases the data recovery is foiled before it ever arrives at our facility by the user when attempting to restore or add a drive to the array post failure. This may lead to an over write of parity or volume data making it much more difficult or impossible to recover from. If you experience a data loss on your RAID, call us at once and we can help minimize your loss and maximize your chance at full RAID recovery.

Below is a list of currently used RAID types and RAID data recovery relevance:

• RAID-0. This technique offers striping but no redundancy of data. It offers the best performance but no fault-tolerance and if a drive fails in RAID 0 only repair and reassembly of the volume will result in a recovery.
• RAID-1. This type is also known as disk mirroring and consists of at least two drives that duplicate the storage of data. This is may become a problem should you experience a corruption of data. You will then have 2 copies of bad data. In a hardware failure scenario mirrors or RAID -1’s can be recovered by software repairs. There is no striping on a 1 and read performance is improved since either disk can be read at the same time. Write performance is the same as for single disk storage.
• RAID-2. This type uses striping across disks with some disks storing error checking and correcting (ECC) information.
• RAID-3. This type uses striping and dedicates one drive to storing parity information. The embedded error checking (ECC) information is used to detect errors. RAID Data recovery is accomplished by calculating the exclusive OR (XOR) of the information recorded on the other drives. Since an I/O operation addresses all drives at the same time, RAID-3 cannot overlap I/O. Should 2 drives in the system fail at once, only hard drive repair and volume restoration using software will result in a RAID data recovery.
• RAID-4. This type uses large stripes, which means you can read records from any single drive. This allows you to take advantage of overlapped I/O for read operations. Since all write operations have to update the parity drive, no I/O overlapping is possible. RAID-4 offers no advantage over RAID-5.
• RAID-5. (Most commonly used) This type includes a rotating parity array, thus addressing the write limitation in RAID-4. All read and write operations can be overlapped. RAID-5 stores parity information but not redundant data (but parity information can be used to reconstruct data if enough of it remains). RAID-5 requires at least three and usually five disks for the array but can hold many more. Again, Should 2 drives in the system fail at once or teh controller card error, only hard drive repair and/or volume restoration using software will result in a RAID data recovery.
• RAID-6. This type is similar to RAID-5 but includes a second parity scheme that is distributed across different drives and thus offers extremely high fault- and drive-failure tolerance. There are few or no commercial examples currently.
• RAID-7. This type includes a real-time embedded operating system as a controller, caching via a high-speed bus, and other characteristics of a stand-alone computer. Recoveries are possible but very difficult do to the proprietary nature of the embedded OS and the storage format of the data.
• RAID-10. This type offers an array of stripes in which each stripe is a RAID-1 array of drives. This offers higher performance than RAID-1 but at much higher cost. Most recoveries cases from RAID 10 are not due to hardware failure, but rather operator error and controller failure.
• RAID-53. This type offers an array of stripes in which each stripe is a RAID-3 array of disks. This offers higher performance than RAID-3 but at much higher cost.

If you need RAID data recovery, contact Data Recovery AID today!