HP 6-Port SATA RAID - Manual (Page 17)

Appendix D: About RAID 17
Appendix D: About RAID
A Redundant Array of Independent Disk (RAID) provides better performance and reliability from combinations of
drives than is possible with the same total storage space without RAID. This Appendix describes the various RAID
levels supported by the 6-Port SATA RAID controller.
The following table shows the number of drives needed and supported for the controller according to RAID level.
Table 2 Drive number limits for a given RAID level
Array type Minimum drive number Maximum drive number
RAID 0 2 6
RAID 1 2 2
RAID 5 3 6
RAID 10 4 6
RAID 50 6 6
Types of volumes and arrays
Simple volume
A simple volume consists of a single drive.
Spanned volume
A spanned volume is created by joining, or concatenating, two or more drives. The drives do not have to be of
equal capacity and are connected end-to-end. A spanned volume offers no redundancy and no performance
advantage over a single drive.
RAID 0
A RAID 0 array is created by striping data across two or more drives. This striping scheme creates no
redundancy to protect the data. However, because the drives share load equally, a RAID 0 array has the best
read and write performance of any RAID type.
In the following figure, the Dn labels (D0, D1, and so on) denote consecutive blocks of data.
Figure 3 A RAID 0 array