Raid: data performance and reliability

RAID, Redundant Array of Inexpensive Disks, is a way of making the performance and reliability of data storage better. There are several common kinds of RAID. They are RAID 0, RAID 1, RAID 5, and RAID 10, which are explained in the following.

RAID 0

In a RAID 0 system, data is spread across two or more hard disks. In this way, data can be written and read faster than using a single disk.

RAID 1

In a RAID 1, data is written to two disks at the same time. If one disk fails, you just need to replace the damaged disk with a new one and the data can be restored from other disk to the new disk.

RAID 5

In a RAID 5, there are at least three disks required. Like RAID 0, data is spread across several disks, but each of them holds "parity" information on the other disks in the array. If one disk fails, its data can be restored to a new disk using the parity information.

RAID 10

RAID 10 focuses on the speed and safety. It is actually a mix of RAID 0 and RAID 1. In it, data is spread across two disks like RAID 0 for the purpose of high speed, but it is also written across two other sets of disks like in RAID 1 for the purpose of safety.

The above are the common types of RAID. You will also see some uncommon RAID like RAID 2, RAID 3, RAID 4, RAID 6, and RAID 7.