What is RAID? RAID (Redundant Array of Independent Disks) creates a single usable data disk, where several physical disks are combined into an array for better speed and/or fault tolerance. Although there are many different levels of RAID, Server Intellect chooses to support the most common raid types: 0, 1, 5, and 10 utilizing hardware RAID controllers for all RAID solutions deployed.
In layman’s terms, this means that several hard drives or disks are combined to create one single disk. There are different advantages and disadvantages to each RAID level. Some may improve performance but are more risky in terms of data loss while with others, the converse is true.
The following is a breakdown of the different RAID levels we provide and their relative strengths and weaknesses.
Implements data striping where file blocks are written to multiple drives. RAID 0 does not provide fault tolerance, because failure of one drive will result in data loss. The purpose of Raid 0 is to dramatically increase read/write times over the use of a single disk. The greater the number of disks in the Raid 0 volume, the greater the read/write performance.
Implements data mirroring. Data is duplicated on two or four drives through a hardware raid controller. It provides faster read performance than a single drive and provides drive redundancy in case of drive failure.
Implements data striping at a block level across three or more drives, and distributes parity among the drives. The parity information allows recovery from the failure of any single drive. Raid 5 allows for increased read/write speeds while allowing the most efficient use of disk space.
Creates multiple mirrors, where data is organized as stripes across multiple disks and then the striped disk sets are mirrored. RAID 10 offers the same fault tolerance as RAID 1 with increased read/write speeds over a single Raid 1 volume or single drive. RAID Level 10 require 4 drives to implement.