How storage devices works


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

Redundant Arrays of Inexpensive Disks (RAID)limited  size  drives.
was introduced to increase the level of
storage, redundancy and augmented performanceEnhanced  Performance
in enterprises and server markets, but now
have become much common with an end user overImproved performance can be found in specific
the  past  5  years.versions of RAID and this performance depends
upon the number of drives used in the array
In simple terms, RAID can be defined as aand the controller. Different RAIDs when
combination of number of low cost hard drivesimplemented provide superior performance in
linked together to form a single largetheir own way and up to different levels, but
capacity storage device with improvedall  improve  in  some  way  or  the  other.
performance, high storage capacity and
reliability of data storage. Use of RAIDLower  Cost
storage technology came into significance in
late 1980s and has marked its presence as theWhen RAIDs were introduced, the cost of
in-demand data storage medium for corporates,implementing them became a key issue. The
professionals, manufacturing units andinvention of RAID was to provide greater
individual users for their need of highstorage capacity as compared to use
capacity  data  storage  device.individual high storage capacity device.
Difference in the cost of high and low
Generally three forms of RAID are used forcapacity drives can be analyzed with a good
desktop computer systems - RAID 0, RAID 1 andexample where three drives of small size cost
RAID  5.less than an individual high capacity drive
which  provides  more  capacity.
RAID 0 is the lowest level of RAID. This
level fails to provide any level ofData  Security
redundancy for the data stored in array. If
any of the drive fails, all the data isThe data which is stored on array is
damaged.completely secured as RAID provides complete
security and competence to protect the data.
RAID 1 provides simple form of redundancy forThis security is followed even if the
data with the help of mirroring process. Thiscomplete hard disk fails without any data
RAID level has two individual drives withloss or performing the restoration process of
same capacity. One is the active drive andthe backed up data. All RAID levels provide
the second is secondary drive termed assame  degree  of  data  security.
mirror. When data is written to the active
drive, it automatically gets copied to theImproved  Accessibility
mirror  drive.
Accessibility refers to availability of data.
RAID 5 is the most powerful and effectiveRAID provides its users to recover data from
level of RAID used on desktop computerhardware  faults  without  any  problems.
system. It requires hardware controller card
to manage the array but in some desktopDisadvantages  of  RAID:
operating system it can be done through
software.RAIDs do give an assured security to the
computer systems but this security cannot be
A minimum of three drives are required torelied upon for long time. If your PC gets
build RAID 5 array with similar drives forattacked by virus, or files and folders are
best  performance.deleted or your PC hits the floor or is
affected by the fire - water damage leads to
Other levels of RAID levels are RAID 0+1,such situations where you don't have any
RAID 10 or 1+0, software and hardware RAIDsother option other than opting for RAID data
which  are  used  for  the  storage  of data.recovery services. There have been many cases
when more than one drive has failed causing
Advantages  of  RAID:an  expensive  RAID  data  recovery.
RedundancyLike such cases, anything is possible and
constant backups should be maintained to
Redundancy becomes the most important featureavoid data loss situations even if you are
while developing the RAID server environment.using  any  reliable  storage  medium.
Redundancy is required in means of performing
backup of data in situations of drive failureConclusion:
in  the  array.
It is agreed that RAID provides PC users with
Capacitya number of benefits depending upon the
version implemented. High storage capacity,
By combining multiple small drives into asecurity, accessibility, performance are the
large array, capacity to store large amountkey features which attract users to opt for
of data increases. The data storageRAID. The advantage of one RAID level over
capability of the operating system increasesthe other cannot be measured as for some
as the RAID server is installed thusapplications RAID 5 is better than RAID 0 and
providing you the freedom to store any amountfor some RAID 0 would be superior to RAID 5.
of data which gets restricted while using the



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