RAID 5 Recovery
Although RAID 5 arrays are fault tolerant, they are not fault proof. R3 Data Recovery regularly see arrays where something has gone wrong. Normally the problems are caused by multiple drive failure, bad advise from support centres or RAID controllers that automatically rebuild arrays – even when you don’t want them to.
RAID level 5 is a method of using hard disk drives in such a way as to provide fault tolerance of hard disk failure via redundancy.
RAID 5 is one of the most common redundancy methods implemented today, the benefits include a tolerance against faults as well as a slight to moderate improvement of the volume read/write speed. Speed improvements on any RAID 5 system are dependent on the number of drives in the system, the quality and type of RAID controller used for the volume and the individual drives themselves.
Speed and redundancy in RAID 5 are provided by distributed Parity. Unlike other RAID solutions, like RAID 3 for example, where a dedicated parity disk is used, in RAID 5 the calculated parity is written to each of the disks in sequence. This essentially removes the bottlekneck of generating the error correction data and writing it to a single hard disk, a process which seriously reduces the performance of the array as a whole. See below for a diagram of how the Parity is distributed across the array in a standard assymetric RAID 5 Array:
The fault tolerance level of RAID 5 implementations is total number of disks (n) minus a single hard disk drive: n-1=fault tolerance
The fault tolerance of a RAID 5 system is always 1 disk, this is a constraint of the way in which the fault tolerance is implemented via an exclusive disjunction, exclusive OR or XOR calculation.
R3 Data Recovery commonly recover data from arrays that others have been unable to. In most cases we can even recover data that has been deemed unrecoverable by others, in cases as extreme as full rebuilds with foreign members present.
Our services can help you to
- Recover your lost data
- Return your system to a bootable/useable state
- Implement appropriate backup solutions
- Advise on ways of securing your data against further loss
To ensure that your RAID 5 Recovery can be completed as quickly and efficiently as possible, it is important that prior to any rebuild attempt that follows a server failure images of all of the member disks are made. Technicians are available to talk you through your data recovery options now, please call on 0800 999 3282 or alternatively Contact Us Here and we will call you straight back.