How storage devices works


RAID - Use Of Multiple Hard Drives For High Storage And Reliability

Redundant Arrays of Inexpensive DisksEnhanced Performance
(RAID) was introduced to increase theImproved performance can be found in
level of storage, redundancy andspecific versions of RAID and this
augmented performance in enterprises andperformance depends upon the number of
server markets, but now have become muchdrives used in the array and the
common with an end user over the past 5controller. Different RAIDs when
years.implemented provide superior performance
In simple terms, RAID can be defined asin their own way and up to different
a combination of number of low cost hardlevels, but all improve in some way or
drives linked together to form a singlethe other.
large capacity storage device withLower Cost
improved performance, high storageWhen RAIDs were introduced, the cost of
capacity and reliability of dataimplementing them became a key issue.
storage. Use of RAID storage technologyThe invention of RAID was to provide
came into significance in late 1980s andgreater storage capacity as compared to
has marked its presence as the in-demanduse individual high storage capacity
data storage medium for corporates,device. Difference in the cost of high
professionals, manufacturing units andand low capacity drives can be analyzed
individual users for their need of highwith a good example where three drives
capacity data storage device.of small size cost less than an
Generally three forms of RAID are usedindividual high capacity drive which
for desktop computer systems - RAID 0,provides more capacity.
RAID 1 and RAID 5.Data Security
RAID 0 is the lowest level of RAID. ThisThe data which is stored on array is
level fails to provide any level ofcompletely secured as RAID provides
redundancy for the data stored in array.complete security and competence to
If any of the drive fails, all the dataprotect the data. This security is
is damaged.followed even if the complete hard disk
RAID 1 provides simple form offails without any data loss or
redundancy for data with the help ofperforming the restoration process of
mirroring process. This RAID level hasthe backed up data. All RAID levels
two individual drives with sameprovide same degree of data security.
capacity. One is the active drive andImproved Accessibility
the second is secondary drive termed asAccessibility refers to availability of
mirror. When data is written to thedata. RAID provides its users to recover
active drive, it automatically getsdata from hardware faults without any
copied to the mirror drive.problems.
RAID 5 is the most powerful andDisadvantages of RAID:
effective level of RAID used on desktopRAIDs do give an assured security to the
computer system. It requires hardwarecomputer systems but this security
controller card to manage the array butcannot be relied upon for long time. If
in some desktop operating system it canyour PC gets attacked by virus, or files
be done through software.and folders are deleted or your PC hits
A minimum of three drives are requiredthe floor or is affected by the fire -
to build RAID 5 array with similarwater damage leads to such situations
drives for best performance.where you don't have any other option
Other levels of RAID levels are RAIDother than opting for RAID data recovery
0+1, RAID 10 or 1+0, software andservices. There have been many cases
hardware RAIDs which are used for thewhen more than one drive has failed
storage of data.causing an expensive RAID data recovery.
Advantages of RAID:Like such cases, anything is possible
Redundancyand constant backups should be
Redundancy becomes the most importantmaintained to avoid data loss situations
feature while developing the RAID servereven if you are using any reliable
environment. Redundancy is required instorage medium.
means of performing backup of data inConclusion:
situations of drive failure in theIt is agreed that RAID provides PC users
array.with a number of benefits depending upon
Capacitythe version implemented. High storage
By combining multiple small drives intocapacity, security, accessibility,
a large array, capacity to store largeperformance are the key features which
amount of data increases. The dataattract users to opt for RAID. The
storage capability of the operatingadvantage of one RAID level over the
system increases as the RAID server isother cannot be measured as for some
installed thus providing you the freedomapplications RAID 5 is better than RAID
to store any amount of data which gets0 and for some RAID 0 would be superior
restricted while using the limited sizeto RAID 5.
drives.



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