What is RAID: Explaining the Tech

What is raid?

RAID stands for Redundant array of inexpensive or independent disk. Actually it is a technology by which we can use more than one physical hard drive simultaneously to get better performance and Data redundancy.
Any user can just plug any number of hard disk in his computer and use them but using a technology like RAID increases the performance and stability of your system.
An SSD is always the fastest solution of data storage but it is not as much secure as some of RAIDs.

Based on the technique of Implementation there are many kinds of RAID available. we have shortlisted some of the most important types of RAID

What is raid?

RAIDs are mostly used in Servers

RAID 0

In this type of RAID all the data is distributed into each disk equally, Confused? Lets simplify it imagine a file, now distribute it into 4 parts, now imagine 2 RAID disks now write data part 1 in drive A , data part 2 into drive B , next Data part 3 into drive A and at last data part 4 into disk B. now writing speed and reading speed will be much more faster, but this performance will come with a risk, if any disk fails all the data will be lost.

RAID 1

It is really simple, it consists of a mirroring. All the data is written into both disks, it increases the writing time but the reading time is decreased. If any disk fails user need not to be worried. All the data can simply be recovered from other volume. In this RAID system the highest reading speed is limited by fastest Disk in RAID whereas writing speed is limited by the slowest Disk in system. There is one more drawback the total size of RAID volume will not be the sum of each disk size but it will be equal to the size of smallest disk.

RAID 5

This technique is a lot complex than the above methods, it requires at least 3 disks to create RAID of this kind. This technology uses block level stripping in the disks and in distributed parity (which means the data that can be used to recover data) .It provides protection against data loss and also slightly improves the performance. In this type of RAID if any disk fails the data is recovered from the distributed data. As this it requires 3 or more disks it us normally used in high performance servers.

 RAID 6

Last but not the least ,RAID 6 uses double distributed parity in block level striping. The major difference between RAID 5 and RAID 6 is that it can withstand the data loss up to two physical disks. That means even if two disks are damaged the data can be restored. If you want to create a RAID with a lot of disks, RAID 6 is really useful.

Which RAID should anyone use? The correct RAID type is based on the use and needs. Simply put, if you need pure performance and you don’t care about data recovery than you can go with RAID 0. If you are not so high on budget but data loss protection is your primary need you should use RAID 1. And if you are going to make a high performance server or NAS then you can use RAID 5 or RAID 6. Although there are other RAID types available. In this article we have only discussed the most widely used standards. Anyone should do his homework about RAID types first before using any kind of RAID system.

GETTING RAID: As RAID can be implemented by using 2 or more disks. There are 2 ways to make it possible :

RAID BY USING SOFTWARE

Modern age software can be used to make a RAID system in a PC. Windows servers support RAID 0 , 1 and 5 where as Windows 8 has introduced a new feature called storage spaces. Apple’s MAC OS X supports RAID 0 and RAID 1.

 RAID BY USING HARDWARE

Any computer user can implement RAID by using a RAID controller. These are supplied with proper drivers and firmware.


Image Credits : dariorug on Flickr, CWCS Managed Hosting on Flickr

 

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