RAID is short for Redundant Array of Independent Disks, was originally referred as redundant array of inexpensive disks. As the word redundant, it copies the data into multiple discs to provide a fault tolerance, improve overall performance. This technology is used in disc drives that are found on servers than personal computers.
How it works?
In RAID, data is copied on to more than one disc in the same array, to ensure that the data is preserved even if any one disc fails. Along with mirroring technology, RAID also provides option to read and write into more than one disc at a same time to improve performance.
As RAID technology is applied on disc drives to store and process large amount of data performance is the key here, it uses different architectures, also called as levels, based on the performances, fault tolerance and desired balance.
Level 0: Striped disk array without fault tolerance
Provides data striping like spreading out blocks of each file across multiple disk drives, not redundancy. This type of architecture improves performance but does not deliver fault tolerance. If one drive fails then all data in the array is lost.
Level 1: Mirroring and duplexing
Provides disk mirroring. This type of architecture provides twice the read transaction rate of single disks and the same write transaction rate as single disks.
Level 5: Block interleaved distributed parity
Provides data striping at the byte level and also stripe error correction information. This results in excellent performance and good fault tolerance. Level 5 is one of the most popular implementations of RAID.
Level 0+1: A Mirror of Stripes
It is not one of the standard RAID architectures, two RAID 0 stripes are created, and a RAID 1 mirror is created over them. Used for both replicating and sharing data among disks.
Hope you all understood what RAID is all about. Share your thoughts below.!!