RAID Levels

What is RAID ?

If you were working on a organisations server environment you will come to hear this term RAID what’s actually RAID stands for, what  it does to the Server or Client PC .First lets figure out what RAID  stands for Redundant Array of Inexpensive/Independent Disk . In general RAID enable system users two or more disk to improve the performance or provide some fault tolerance solution to the organization, fault tolerance means providing some safety net to failed hardware and ensure that the failed hardware computer can still operate (most of the time HDD ). RAID level depends on how many drives you used ,most of the organizations and data centers are the trend to use RAID to protect their data from lost

Overview of RAID

This is traditionally implemented by businesses and organizations to reduce the disk tolerance and optimize the performance because its must to have good performing serves and NASes(Network Attached Storage’s) in their organizations. Servers,NASes  and data-centers they usually have RAID controllers. This feature support multiple SSD(Solid State Drivers) and SATA drives depending on what configuration applies.

There are two RAID types Software RAID and Hardware RAID , software RAID means you can set up RAID without need for a dedicated hardware RAID controller some OS inherently come with RAID capabilities like windows 8 Storage spaces and windows 7(Pro & Ultimate). These RAID capabilities are available in other OS include OS X Server,Linux & windows Server

 RAID Levels

  • RAID 0

This level is used to boost the server performance this called as “disk strapping “, to use this you must have at-least two drivers in this data is written across multiple disks ,this means the work that the computer use is handled by multiple disks  rather than one due to that it increase the performance because multiple disks are reading and writing data it improves disk I/O.Both volumes in disks are same size. Both software and hardware RAID support. The downside of this is there are no fault tolerance if one disk fails losing data and corruption increase

  • RAID 1

We can use this as a fault tolerance  configuration it known as  “disk mirroring” by this RAID data is coped simultaneously from one disk to another creating a replica of the disk the advantage of this is if one disk fried we can use other drive can keep working. he downside of this is the slight drag of performance. we can implement this by software RAID and hardware RAID.Minimum two disks required with software RAID we can use two use two volumes in single disk to mirror. This cuts the capacity by half

  • RAID 5 

This the most common RAID configuration used by the businesses and organization servers and NASes. This RAID level provide better performance than mirroring as well as fault tolerance.In this data and parity are striped across three disks  if one disk gets error or start to fail it recover data from the parity on distributed disk automatically .Essentially the system is still work  even the disk is damage until you replace the damage disk another advantage of this is its “hot-swappable”   that means in case the drive fails we can replace the drive without turn of the servers functionality. The downside of this is performance hit  for the servers that have a lot of write operation

  • RAID 6

This is also used in frequently in enterprises its identical to the RAID 5 but this used one additional parity block than RAID 5

  • RAID 10

It’s a combination of  RAID 1 and 0,its donated as RAID 1+0.Its a combination of RAID 1 mirroring and striped in RAID 0. This RAID level gives the best performance but to deploy this its costly required twice as many disks as other RAID levels . Its requires a minimum of four disks, this RAID level ideal for high utilized database servers witch performing more write operations. We can implement this by software and hardware base but its more suitable for use hardware level

There are other RAID levels: 2, 3, 4, 7, 0+1 but they are really variants of the main RAID configurations already mentioned above, and they’re used for specific cases.