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RAID disc drives - very reliable - what if they fail?!

ALL IS NOT LOST. If your data is on a RAID array of disc drives and something has gone wrong which even the advanced multiple redundancy systems of RAID can't recover, you can still get your data back most likely by Ontrack Data Recovery, who have helpfully sent us this article:

"Although RAID (Redundant Array of Independent Disks) technology has been around for many years, more and more companies rely on these systems to manage their storage needs as their vast amounts of data grow at an alarming rate.  As many familiar with RAIDs already know, these systems offer significantly better reading/writing speed than single drive servers and provide better fault tolerance for when a drive fails. This is an important point as today’s businesses are focused on finding solutions that can protect their data and help them avoid the downtime that accompanies data loss.

RAID systems are great for data protection because they generally allow data to be written to multiple hard disk drives so that a failure of any one drive in the array does not result in the loss of any data, as well as increasing the system’s fault tolerance. Fault tolerance refers to a system’s ability to continue operating when presented with a hardware (or software) failure, as should be experienced when a hard drive fails in one of the redundant configurations of RAID. Because RAID systems offer this built-in protection, most businesses rely on them to house their mission critical data such as financial data and business system data (email, back office, large database application data).

But what happens when there is a major issue with the RAID system that results in the data becoming inaccessible? Although RAIDs are specifically created to guard against data loss, they are still susceptible to total system failures if multiple drives experience problems at the same time. Other problems can occur when RAID controllers don’t recognise the drives in the array or if a drive is removed from a hot swappable drive bay and a new one is replaced in the wrong order. The bottom line is that, just like single hard drive systems, RAID systems can also experience problems that can lead to data loss – the difference is, with a RAID failure, the problem can literally cripple a business or halt operations since the data stored on the RAID array is usually business critical.

Unfortunately, after experiencing a RAID malfunction, many businesses give up hope if they are told by their own IT staff, vendors, technical support or consultants that their data is inaccessible with no chance for recovery. When RAID problems happen, most think it is the end of the line for that data – if the RAID is broken, there is no way to get the data back. This simply isn’t true and businesses need to know that they do have options if their RAID system stops working. Data recovery providers can fix broken RAIDs, but the key is to work with RAID recovery experts to ensure that the most critical data has the best chance to be saved.

Often times, IT staff will attempt to fix the system by relying solely on the original RAID configuration, documented administrative procedures, or will attempt to force a RAID controller or drives in a RAID into a particular configuration which usually results in even greater damage to the customer’s data.  However, RAID experts, such as those at Ontrack Data Recovery, the industry’s leading data recovery provider, know that rather than forcing normal procedures,  one should figure out the RAID “by hand,” which means that they look at every sector of data across all of the drives in a system to put it back together. Specifically, RAID experts don’t rely on the original RAID configuration because it may have flaws in it – By rebuilding the distributed data blocks, drive order and data symmetry manually, even the most challenging RAID system can be recovered.  

Experienced Engineers even have the ability to work on RAID systems if the original hard drive has failed through reconstructing the RAID virtually. More importantly, some experienced companies can often recover the RAID system in the field remotely via Internet or dial-up connection so the customer doesn’t have to pull out drives and racks for shipping. This is an important benefit as it allows the fastest possible recovery for critical data – often times getting businesses back up and running in only a matter of hours.

With a double-digit increase in RAID recoveries over 2005, Ontrack is constantly working on RAID systems, improving their recovery techniques and providing unmatched results for grateful customers. It is also important to note that an advantage of data recovery is its ability to get back the most recent files versus the most recent backups – a crucial distinction since RAIDs often store the highest value data.

Marc Valle from GBDH Design Group, an architectural-engineering business based in Sacramento, Calif. says they were in the process of transferring data to a new server when one of the drives in the RAID system failed.  As such, they were unable to have a complete back-up prior to the operation.  With mission critical data lost, Marc was panicked that the company would not have been able to continue in business without the data.  After using a recovery service that was inexperienced in RAID arrays, they turned to Ontrack Data Recovery who was quickly able to recover 99 percent of the data and keep them operating".

...Realities of RAID - Data Loss Still Exists - RAID Data Recovery by Kroll Ontrack