Introduction:
RAID expands to Reduntant Array
of Independent Disk, is a data storage technology which coalesces the
disk drives into a single logical unit for the purpose of enhancing
the performance and data redundancy. Basically RAID is the policy to
spread the data across multiple disk in a reliable manner. This
technology comprises of certain levels which makes the task of
data storage easier.
RAID levels:
The popular levels of RAID are
RAID 0, RAID 1, RAID 5, RAID 6 and RAID 10. RAID 0 is mainly used for
striping, that is to read and write the data pararellely
across the disk to achieve performance.
The main function of another level RAID
1 is mirroring, which helps to maintain the mirrored sets of
the hard drive. In this case, if the hard drive get fails or data is
deleted accidently then there is another mirrored drive which consist
of the identical data. Although this feature require double storage
capacity but it ensures high data protection and performance.
Now comes the RAID 4 which has the
splendid characteristic of parity, which is used to detect the
fault tolerence. It is used to recover the lost data in case of disk
drive failure. RAID 4 consist of 3 hard disk drives in which 1 is for
checking parity. One of the most prominent feature of RAID 4 is hot
sparing that is it has the power of replacing the failed disk
automatically. Inspite of all these features this level is not so
commonly used.
The reason is RAID 6 which has 2 parity
disk means it has the capacity to replace 2 hard drive failures
automatically. Most widely used out of all levels of RAID is RAID 10.
However, in this level, order of the required task is maintained.
First mirroring is done and then the data is striped across the disk
drives. Its is commonly called as the “stripes of mirrors” the
fruitful combination of RAID 0 and RAID 1.
RAID in OS X Disk Utility:
Most commonly OS support RAID
technology software for managing the volumes such as Mac OS X Disk
Utility. Data is distributed across multiple disk either by hardware
RAID or software RAID. Software RAID is implemented as a single
virtual device which consist of a standard drive controller chip
inbuilt into it with the drivers in it as well. Now if we compare
this with the hardware RAID then this software RAID involves less
number of CPU cycles and power to run.
RAID in Disk Utility is a built in
software which support few levels of RAID. Mac OS X disk utility
supports RAID 0, RAID 1 and RAID 10. Software RAID is reliable and
flexible for the overall functioning of the system as it maintains
the storage effectively without any loss of data. The two efficient
feature of the Mac OS X Disk Utility is striping and
mirroring. Striping stores the files in segments across the
disk which is beneficial in when we have to deal with large sets of
data whereas mirroring helps to duplicate the content of the data on
to the another drive. After clicking on the RAID option in Disk
Utility, just choose RAID type and format according to the data
requirement and create sets. These sets will helps us to manage the
data enthusiastically.
So, the above content describes the
introduction and overall view of RAID to utilize the best service in
an efficient manner.