Other articles in this glossary

HARDWARE: SAN, Rackmount Servers, more...

SOFTWARE: CRM, Solaris, more...

Services: Data Recovery, Dedicated Hosting, more...

Technologies: RAID, Distributed Computing, VoIP, more...

RAID products

Risks of using RAID

At the very simplest level, RAID combines multiple hard drives into a single logical unit. Instead of seeing several hard drives, the OS sees only one. RAID is typically used on server computers, and is usually done with identically sized disk drives. With decreases in hard drive prices and wider availability of RAID options built into motherboard chipsets, RAID is also being found and offered as an option in more advanced personal computers. This is especially true in video and audio editing systems. More

Short for Redundant Array of Independent (or Inexpensive) Disks, a category of disk drives that employ two or more drives in combination for fault tolerance and performance. RAID disk drives are used frequently on servers but aren't generally necessary for personal computers. More

RAID under Linux

RAID under Apple

RAID under Windows

What is RAID, RAID explained?

Definition: RAID stands for Redundant Array of Independent (or Inexpensive) Disks. It involves the configuration (setting up) of two or more drives in combination for fault tolerance and performance. RAID disk drives are used frequently on servers and are increasingly being found in home and office personal computers.

RAID is a method of creating one or more pools of data storage space from several hard drives. It can offer fault tolerance and higher throughput levels than a single hard drive or group of independent hard drives. You can build a RAID configuration with IDE (parallel ATA), SATA (Serial ATA) or SCSI hard disks or, in fact, even drives like the old 3.5" floppy disk drive!

RAID setupThe exact meaning of RAID has been much debated and much argued. The use of "Redundant" is, in itself, a contentious point. That several manufacturers have deviated from accepted RAID terminology, created new levels of disk arrangements, called them RAID, and christened them with a number has not helped. There are even some single disk RAID configurations! Double parity, RAID 1.5, Matrix RAID etc., are examples of proprietary RAID configurations.

Data can be distributed across a RAID "array" using either hardware, software or a combination of the two. Hardware RAID is usually achieved either on-board on some server class motherboards or via an add-on card, using an ISA/PCI slot.

RAID arrangements are used for Network Attached Storage.

RAID 0 and RAID 1 the most common types of RAID

Other types of RAID: include RAID-0, RAID-1, RAID-0+1, RAID-1+0, RAID-10 (1+0, 10 refer to the same thing), RAID-2, RAID-3, RAID-4, RAID-5, and RAID-6