RAID
RAID
Updated on 16 May 2025

RAID Definition

A Redundant Array of Independent Disks (RAID) is a method of configuring member drives to create high availability and high performance systems. The RAID level provides different degrees of redundancy and performance; it also determines the number of members in the array

RAID level

The RAID level is what determines the relationship of the disks.

Level Description Drive count Approximate array capacity Redundancy
RAID 0 RAID 0 combines two or more disks by stripping data across them.
That chunks of data are written to each disk in the array alternately.
1 - 8 Drive count * Drive size None
RAID 1 RAID 1 is a configuration that mirrors data between two or more disks.
Everything written to the array is placed on each of the devices in the group, so each disk has a complete set of the available data.
2 Drive size 1

Redundancy means how many drive failures the array can tolerate. In some circumstances, an array can tolerate more than 1 drive failure.