Operations Manual
7RAID
RAID is an acronym for Redundant Array of Inexpensive (or Independent) Disks. This section provides a
7.1RAID Defined
RAID is a way of storing data on two or more physical disks for the purpose of redundancy, improved performance, or both. The combined physical disks make up what is called an array. This array appears on the host system as one disk. For example, if you have physical disk 1 and physical disk 2, those two disks appear to the host system as one disk.
RAID consists of different levels, which determine how the data is placed in the array. Each RAID level has specific data protection and system performance characteristics. The following are commonly used SCSI RAID levels:
1.RAID Level 0: Striping, good performance, no redundancy
2.RAID Level 1: Mirroring,
3.RAID Level 5: Striping with parity striped across all drives; offers performance and redundancy
4.RAID Level 10: Mirroring and striping; best redundancy and best performance
5.RAID Level 50: Parity striped across all drives in a mirrored set; redundancy and performance
You can manage RAID arrays with a RAID controller (hardware RAID) or with software alone (software RAID).
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Part Number: 1008080 | Page 62 of 82 |
Version 1.4. 01/12/2010 |
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