RAID Data Recovery can be one of the most optimistic scenarios for data recovery, even when one hard drive has suffered from mechanical failure. If you do find yourself with a failed hard drive (or two) from a RAID 1 or 5 array, ECO Data Recovery can restore or recover your RAID, SAN, NAS, Snap Server. We run multiple, terabyte capable servers to tackle the larger RAID’S that arrive here for RAID data recovery.
(Never Re-initialize your RAID array!)
Utilizing custom software and hardware solutions, ECO Data Recovery is the ONLY choice for your vital data. Don’t be misled by companies that offer on-site or worse, remote recovery options if one of the drives have suffered from a mechanical failure. Before any utilities are run against a RAID, any physical issues must be overcome and all of the disks must be cloned sector by sector. (This is providing that all of the hard drives in the RAID array are in good working condition.) Anything less is possibly an irreparable accident waiting to happen. Just one foul up and ALL of your data can be lost. We have recovered RAID’s that have been at many of our competitors labs.
RAID Data Recovery Services
RAID 0, 1, 5, 10
In this day and age, there are more and more companies utilizing large storage units. There is NO data recovery company that has the RAID Data Recovery experience of working with, and recovering data from RAID devices that our company has.
What a RAID (Redundant Array of Independent Disks) is:
RAID 0: (Also known as “Striped” or “Spanned” Volume)
All the disk devices are organized alternatively so that blocks are taken equally from all disks alternatively, in order to reach higher efficiency. Since the probability of finding a block of a file is identical for all disks, there are force to work simultaneously thus making the performance of the Meta disk almost 10 times that of a single disk.
RAID 1: (“Mirroring” or “Mirrored Set”)
In this mode, the goal is to reach the highest security of the data. Blocks of data are duplicated in all physical disks (each block of the virtual disk has a duplicate in each of the physical disks). This configuration provides 10 times the reading performance of a single device, but it degrades writing operations. Read operations can be organized to read 10 blocks simultaneously, one from each device at a time. Similarly when writing 1 block it has to be duplicated 10 times, one for each physical device. There is no advantage in this configuration regarding storage capacity.
In this mode the ultimate goal is to balance the advantages of the type RAID0 and RAID1. Data is organized mixing both methods. The physical 1 to N-1 are organized in striping mode (RAID0) and the Nth stores the parity of the individual bits corresponding to blocks 1 to N-1. If any of the disks fails, it is possible to recover by using the parity information on the Nth hard disk. Efficiency during read operations is N-1 and during write operations is 1/2 (because writing a data block now involves writing also to the parity disk). In order to restore a broken hard disk, one only has to re-read the information and re-write it (it reads from the parity disk but it writes to the newly install hard disk).
This type is similar to RAID 4, except that now the information of the parity disk is spread over all the hard disks (no parity disk exists). It allows reducing the work load of the parity disk, that in RAID 4 it had to be accessed for every write operation (now the disk where parity information for a track is stored differs for every track)
Block-level striping with double distributed parity. Provides fault tolerance from two drive failures; array continues to operate with up to two failed drives. This makes larger RAID groups more practical, especially for high-availability systems. This becomes increasingly important as large-capacity drives lengthen the time needed to recover from the failure of a single drive. Single-parity RAID levels are as vulnerable to data loss as a RAID 0 array until the failed drive is replaced and its data rebuilt; the larger the drive, the longer the rebuild will take. Double parity gives time to rebuild the array without the data being at risk if a single additional drive fails before the rebuild is complete.
RAID 0+1: striped sets in a mirrored set (minimum four disks; even number of disks) provides fault tolerance and improved performance but increases complexity. The key difference from RAID 1+0 is that RAID 0+1 creates a second striped set to mirror a primary striped set. The array continues to operate with one or more drives failed in the same mirror set, but if drives fail on both sides of the mirror the data on the RAID system is lost.
As there is no basic RAID level numbered larger than 9, nested RAIDs are usually unambiguously described by concatenating the numbers indicating the RAID levels, sometimes with a “+” in between. RAID 1+0 – mirrored sets in a striped set (minimum two disks but more commonly four disks to take advantage of speed benefits; even number of disks) provides fault tolerance and improved performance but increases complexity.
RAID is NOT Data Backup!
A RAID system used as a main drive is not a replacement for backing up data. Data may become damaged or destroyed without harm to the drive(s) on which they are stored. For example, some of the data may be overwritten by a system malfunction; a file may be damaged or deleted by user error or malice and not noticed for days or weeks. RAID can also be overwhelmed by catastrophic failure that exceeds its recovery capacity and, of course, the entire array is at risk of physical damage by fire, natural disaster, or human forces. RAID is also vulnerable to controller failure since it is not always possible to migrate a RAID to a new controller without data loss.
RAID drives can make excellent backup drives, when employed as backup devices to main storage, and particularly when located offsite from the main systems. However, the use of RAID as the main storage solution cannot replace backups.
RAID Data Recovery In The Event of a Failed Array:
With larger disk capacities the odds of a disk failure during rebuild are not negligible. In that event the difficulty of extracting data from a failed array must be considered. Only RAID 1 stores all data on each disk. Although it may depend on the controller, some RAID 1 disks can be read as a single conventional disk. This means a dropped RAID 1 disk, although damaged, can often be reasonably easily recovered using a software recovery program or CHKDSK. If the damage is more severe, data can often be recovered by professional drive specialists. RAID5 and other striped or distributed arrays present much more formidable obstacles to data recovery in the event the array goes down.