Failed RAID array

Overview

RAID, or Redundant Array of Independent Disk, is a term used to describe the storage schemes which essentially involves dividing as well as replicating the data amongst the multiple hard disks. The two main goals of RAID include increasing the reliability of data and along with improving the Input/Output performance. RAID has a number of different levels and may or may not be fault tolerant.




Use of RAID

RAID is used in order to combine different physical hard disks into one single logical drive by using either software or hardware. They key concepts of RAID include mirroring and copying data to different disks, splitting the data as well as correcting the errors. RAID is primarily used for improving reliability, protecting data that is important for a business such as databases of orders of customers, and at places where high speed is required.

Need for recovering RAID

Raid has an in-built tendency to protect the data from drive failures. In order to maintain this protection, the need to immediately replace the failing or failed drives in the array becomes essential. The damaged RAID should immediately be replaced as the risk of another drive suffering a breakdown increased due to the lack of protection. Most of the RAID levels can survive failure of a single drive. However, they cannot endure a second drive failure.

It is often believed that drive failures are entirely independent of each other. However, this is not completely true. All drives in the array are absolutely identical and any defect in one of them will affect all drives in the array.

Process of Recovering RAID data

In order to recover the RAID Data, the first thing to be done is to acquire the images from each member of the array. In this way, the physical issues are separated and its working copies are obtained. Each and every sector of the hard drive must be read to ensure that all the required information and data is successfully acquired. Once the data is obtained, the logical structure of the original media is produces and the data is copies to a stable media.

The failure of RAID array can lead to the loss of important data and can lead to serious business losses. Recovering failed RAID array is a task better left to competent data recovery service providers and their experienced professionals. Data recovery services have the ability to recover data from all kinds of failed RAID’s such as basic spanned, striped volumes or the parity-distributed. There is no need of any cables, controllers or enclosures for recovering the lost data; all that is required is the active members of the array. The procedures that are performed in order to recover the data from the failed RAID are performed on the images created from the original drives, not on the drive itself. There are special software which help in extracting data from these images. After determining the course of action to be followed, the client is given a detailed quotation of the process. On receiving the approval of the client, the process of recovery begins.



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