RAID Array Recovery.

RAID Recovery

RAID Recovery – If you have experienced a failed server or RAID array call us today – (01) 8612280.

CDS specialises in RAID recovery – restoring mission-critical data from all server and drive manufacturers that may have suffered:

We understand the critical nature of these types of system failures and offer unbeatable turnaround, with data returned in many cases within 48 hours depending on system configuration and complexity. Depending on their configuration RAID arrays can usually tolerate a single drive failure without impact on the server’s availability on your network. However, if more than one drive fails, the server usually will no longer boot. You can try to recover the data yourself, though we have frequently seen this type of intervention result in permanent data loss. A server failing may not cost you your job, but your unsuccessful intervention causing a permanent data loss might not be viewed with quite so much understanding.

In case of a RAID/Server failure, Shut down the server immediately!

• If you are unsure of the damage, do not try to reboot as this may cause further damage to the array.
• If a drive is making unusual mechanical sounds, shut it down immediately.
• Log the failure and events/observations that preceded system failure.
• Before removing drives from an array, label the drives position in the array making note of any drives that have fallen offline. (Drives will be numbered starting with 0 Example: If you have a 5 drive array they will be numbered 0-4)
• Do not run repair or defrag utilities on suspected bad drives.
• Do not swap or re-arrange the order of the drives in a multiple drive array as this may cause overwriting.
• Do not replace the failed drive with a drive that was part of a previous RAID system.

RAID Recovery Process – An Overview

The process is time consuming due to a number of factors including the volume of data, the number of devices involved, the complexity of correctly establishing the precise RAID attributes and the need at all times to avoid the manipulation of the original drive set by working with an equivalent set of drive images.

We can recovery virtually any RAID system, from home NAS to Enterprise RAID. We routinely recover from the following:

RAID Recovery Process

• The first stage of the process involves a diagnosis of each drive from the array, in order to detect how the array might have originally failed.

• Defective drives must be repaired in preparation for the subsequent imaging process.

• Each available drive is fully imaged using a highly fault-tolerant bit-imaging system in order to get the best quality image from each drive in the array.

• The series of images is then used to reconstruct the array, as the original drives may in fragile condition. From the point of view of best practice, it is essential to manipulate the images and not the original drives.

• Once enough drive images are available with the requisite data quality, it is then necessary to analyse the data on each disk in order to determine the parameters of the system which determine how the images are ‘merged’ to create the original logical volume.

• Once a logical volume can be created, tested and verified, the data is exported to an external hard drive from where it can be re-imported to your server once the system has been made bootable.