RAID Data Recovery Center is unmatched when it comes to RAID Data
Recovery and Repair. Our technicians are capable of recovering and repairing
inaccessible data from nearly all forms of RAID system servers including:
•file servers
•application servers
•web servers
•network attached storage
•RAID systems of any size
All RAID recovery work is done on-site in our own class 100 clean room.
Regardless of the problem, manufacturer, or operating system, we handle
it all:
Problems
•Unbootable Systems
•Corrupted RAID
•Missing Partitions
•Controller Failure
•Computer virus and worm damage
•Natural Disaster
•Human Error
Manufacturers:
•Adaptec
•AMI
•Bus Logic
•Compaq
•HP
•Mylex
•PERC
•Pinnacle
•Promise
•Raidtec
•Software RAIDS
•Storage Dimensions
•Sun
•3ware
Operating Systems:
•Windows NT
•Windows XP
•Windows 2000
•Windows 2003
•Microsoft Exchange
•Sun Solaris
•IBM AIX HP UX
•LINUX
•UNIX
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.
What are the different RAID levels?
A research group at UC-Berkeley coined the term "RAID", 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.
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Which RAID level should I use?
The right choice depends on the application. The RAID Levels below provide
a brief summary and general uses. Keep in mind, Adaptec RAID controllers
do not support all RAID Levels. Please check Technical Specifications
for your RAID product for RAID Levels that are supported.
RAID Level Uses
Level 0 (striping)
Any application which requires very high speed storage, but does not
need redundancy. Photoshop temporary files are a good example.
Level 1 (mirroring)
Applications which require redundancy with fast random writes; entry-level
systems where only two drives are available. Small file servers are
an example.
Level 0/1 or 10 (mirroring and striping)
Dual level raid, combines multiple mirrored drives (RAID 1) with data
striping (RAID 0) into a single array. Provides highest performance
with data protection.
Level 5 (distributed parity)
Similar to level 4, but may provide higher performance if most I/O is
random and in small chunks. Database servers are an example.
Level 0/5 or 50
Dual level raid, combines multiple RAID 5 sets with data striping (RAID
0). Increased reliability and performance over standard RAID5 that can
stand a multiple drive failure; one hard drive per RAID5 set.
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To proceed do one of the following:
Fill out an online data recovery
quote form - a representative will get back to you within an hour
of submittal.
Call 13391703060
( our toll-free number is at the top of every page) to speak with a
representative and receive your quote over the phone. We answer our
phones 24 hours a day 7 days a week.
Fill out a data recovery request
form and ship us your drive. please follow any instructions
on how to package and ship a hard drive.