RAID DATA RECOVERY:
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Our
data recovery technicians are capable of recovering and repairing
inaccessible data from all forms of RAID system servers including:
file servers, application servers, web servers, network attached storage
RAID systems of any data size.
What is RAID?
RAID is an acronym for Redundant Array of Inexpensive (or Independent) Disks. A
RAID array is a collection of drives which collectively act as a single storage
system, which can tolerate the failure of a drive without losing data, and which
can operate independently of each other.
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What are the different RAID levels?
A research group at Berkeley University in the United States coined the term "RAID",
(short for Redundant Array of Inexpensive Disks) defining six RAID
levels. Each level is a different way to spread data across multiple drives--a
compromise between cost and speed. Understanding these levels is important,
because each level is optimized for a different use.
RAID Level 0 is not redundant, hence does not truly fit the "RAID" acronym.
In Level 0, data is split across drives, resulting in higher data throughput.
Since no redundant information is stored, performance is very good, but the
failure of any disk in the array results in all data loss. This level is
commonly referred to as striping.
RAID Level 1 is commonly referred to as mirroring with 2 hard drives. It
provides redundancy by duplicating all data from one drive on another drive. The
performance of a Level 1 array is slightly better than a single drive, but if
either drive fails, no data is lost. This is a good entry-level redundant
system, since only two drives are required. However, since one drive is used to
store a duplicate of the data, the cost per megabyte is high.
RAID Level 2, which uses Hamming error correction codes, is intended for use
with drives which do not have built-in error detection. All SCSI drives support
built-in error detection, so this level is of little use when using SCSI drives.
RAID Level 3 stripes data at a byte level across several drives, with parity
stored on one drive. It is otherwise similar to level 4. Byte-level striping
requires hardware support for efficient use.
RAID Level 4 stripes data at a block level across several drives, with parity
stored on one drive. The parity information allows recovery from the failure of
any single drive. The performance of a level 4 array is very good for reads (the
same as level 0). Writes, however, require that parity data be updated each
time. This slows small random writes, in particular, though large writes or
sequential writes are fairly fast. Because only one drive in the array stores
redundant data, the cost per megabyte of a level 4 array can be fairly low.
RAID Level 5 is commonly referred to as striping with distributed parity.
RAID Level 5 is similar to level 4, but distributes parity among the drives. No
single disk is devoted to parity. This can speed small writes in multiprocessing
systems. Because parity data must be distributed on each drive during reads, the
performance for reads tends to be considerably lower than a level 4 array. The
cost per megabyte is the same as for level 4.
RAID 0/1 or10 is a dual level array that utilizes multiple RAID1 (mirrored)
sets into a single array. Data is striped across all mirrored sets. As a
comparison to RAID 5 where lower cost and fault tolerance is important, RAID 0/1
utilizes several drives, in order to provide better performance. Each drive in
the array is duplicated (mirrored). This eliminates the overhead and delay of
parity. This level array offers high data transfer advantages of striped arrays
and increased data accessibility (reads). System performance during a drive
rebuild is also better than that of parity based arrays, since data does not
need to be regenerated from parity information, but copied from the other
mirrored drive.
RAID 0/5 or 50 is a dual level array that utilizes multiple RAID5 sets into a
single array. In RAID 0/5 array, a single hard drive failure can occur in each
of the RAID5 without any loss of data on the entire array. Keep in mind, as the
number of hard drives increase in an array, so too, does the increased
possibility of a single hard drive failure. Although there is an increased write
performance in RAID 0/5, once a hard drive fails and reconstruction takes place,
there is a noticeable decrease in performance, data/program access will be
slower, and transfer speeds on the array will be effected.
Data Recovery Lab can recover hard drives
attached to RAID interfaces by the following manufacturers:
Adaptec, AMI, Bus Logic, Compaq, HP, Mylex, PERC, Pinnacle, Promise, Raidtec, Software RAIDS, Storage Dimensions, Sun, 3ware,
Data Recovery From RAID Arrays Under The
Following Operating Systems:
Windows NT, Windows XP, Windows 2000, Windows 2003, Microsoft Exchange, Sun, Solaris, IBM AIX HP UX, LINUX, UNIX
Data Recovery From Different Types of RAID:
RAID-0
RAID-1
RAID-5
RAID-6
RAID-10
JBOD |
Striped Array
Data Recovery
Mirror Array Data Recovery
Parity Striped Array Data Recovery
Double Parity Data Recovery
Mirroring & Striping
Spanned Disks Array Data Recovery |
Data Recovery Lab specialises in recovery of RAID Servers including:
SATA RAID Data Recovery;
SCSI RAID Data Recovery;
Adaptec RAID SATA SAS SCSI Data Recovery;
Promise RAID SATA SAS SCSI Data Recovery;
3Ware RAID SATA SAS SCSI;
Dell Striped RAID Data Recovery;
Highpoint RAID Controllers Data Recovery;
VIA and nVidia RAID Recovery;
Buffalo TeraStation Pro NAS 0.6 TB HD-H0.6TGL/R5;
Buffalo TeraStation Pro NAS 1.6 TB HD-H1.6TGL/R5;
Buffalo TeraStation Home Server NAS 1.0TB HS-D1.0TGL/R5;
Buffalo TeraStation Home Server NAS 2.0TB HS-D2.0TGL/R5;
Buffalo TeraStation Pro NAS 1.0 TB TS-1.0TGL/R5;
Buffalo TeraStation Pro NAS 2.0 TB TS-2.0TGL/R5;
Buffalo Linkstation HD-H250LAN;
LACIE Ethernet Disk;
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