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An Introduction To Raid - Greater Reliability ,faster, Less Costly Hard Drive Units

What  is  a  raid setup on a computer system?come to mind are game servers and peer to
peer (P2P) file or music file sharing
Like anything else it depends who you talkservers.
to.
However since there is no allocation for
Raid hard drive systems had their acronymerror correction or redundancy RAID 0 is not
explained as "Redundant Array of Individuala safe system for vital data. Data will be
Drives "and "Redundant Array of Inexpensivelost on disk failure. Only use RAID 0 in
Drives". The acronym for this is thesituations where you need the extended disk
shortened  term  "RAID".capacity or performance gain but not enhanced
data  reliability.
Capacity, reliability and performance are all
important for file servers or other computerSecondly  in  sequence there is RAID Level 1.
systems when you are storing large or very
important  files.In the same way that RAID 0 focuses solely on
storage capacity and performance with no
It is often said that "It is not if you hardconcern whatsoever on reliable data storage
drive will fail. It is at what point in timeRAID 1, which us also called "Disk Mirroring"
your  hard  drive  will  fail".uses disks in pairs to save the files in a
redundant  manner.
Of course if your hard drives fail even if
you have backup the last bit of data whichSeveral  points.
was being written onto the hard drive when
the  failure  occurred  will  be  lost.One performance may be slower as it takes
time for the host adapter to send the data
You can get much greater capacities, avoidand  for  the  drives  to  write  it to disk,
losing data from disk failure, and do all
this with the RAID (the acronym for theSecondly a user may delete or damage files
system).which of course will be stored in that way on
both  drives.
RAID can now be done with standard
commercially available hard drives so theRaid 1 hence offers better reliability than
cost is now within your price range for allRAID 0 or the conventional drive setups but
the benefits and peace of mind RAID will givedoes not give full security for your data or
you.enhanced  performance.
RAID can be simply explained as putting theNext in sequence we have RAID Levels 2, 3 and
hard  drives  in  parallel  sequence.4.
The host adapter (usually called the RAIDRaid 2 adds one or more disks to hold error
system controller) sits between one highercorrection codes with which lost data can be
stream (on the computer side) and severalreconstructed.
lower rate data streams (on the hard drive
side). When the computer writes to the disksRaid Level 3 is the same as RAID Level 2 but
, the host adapter takes high stream data anduses a simpler code the maximum storage
breaks it into many synchronized streams ,capacity  with  Raid  3 may be somewhat less.
one for each of the disks in process called
"Striping ". Upon reading the data the hostRaid Level 4 is nearly the same as RAID LEVEL
adapter takes the data stream from each disk3 but instead of "Striping " across disks is
multiplexes the sets of data streams andoperates at a sector level, You now have the
coordinates sending the resulting combinedbetter situation of both a simpler , less
set  of  data  onto  the  computer.intensive demanding system and as well as
good data reliability . In addition
It is all a matter of redundancy which makesperformance may be enhanced as large data
RAID  such  a  good  thing  in  most  cases.blocks can be written faster due to more
coordinated writing to the drives in smaller
There are six different levels of RAID"sector"  areas.
functionality depending on your requirements.
- the level of data security and integrityLastly  is  RAID  Level  5.
you want as well as the size of hard drive
space  you  want.Raid level 5 is the same as the excellent
RAID Level 4 except that instead of
First of RAID Level 0 which spreads the datadedicating a single disk to storing the data
across multiple disks. You can get a similarthe data stream is striped across all the
effect to the RAID Level 0 by having multipledisks. You have greater performance with
disks and using the features in Windows 2000greater reliability for your computer
or  its  successor  Windows  XP.systems.
Since the data volume and rate to anyA RAID setup may take some effort and
specific disk is a fraction of the aggregatetraining  on  your  part.
you will receive larger capacity and better
performance from a RAID 0 setup than from anyBase your planning for your new RAID system
one  conventional  disk.on  a  careful  analysis  of  your  needs.
As well data can be sourced from multipleWhat is important in your situation
drives as once. This can be most useful incurrently? Disk size capacities, data
shared situations which may benefit fromreliability and integrity, performance or a
enhancements in speed, two examples whichcombination or all.



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