Raid Levels; Disk Group - NEC Express5800 series User Manual

RAID Levels

The record mode enabling the RAID feature includes several levels. Among the levels, the Internal
RAID Controller supports RAID levels 0, 1, 5, and 6. The number of hard disk drives required to
create a disk group varies depending on the RAID level as shown in the table below.
RAID level
RAID 0
RAID 1
RAID 5
RAID 6
NOTE:
later in this chapter.

Disk Group

A disk group is configured with more than one HDDs.
The allowable number of disk groups is equal to the number of HDDs.
The figure below shows a sample configuration. The three HDDs are connected to the Internal
RAID Controller, creating one disk group (DG).
HDD 1
(36 GB)
Number of required HDDs
Min.
1
2
3
3
For details of the RAID levels, see "RAID Levels" described
RAID Controller
HDD 2
(36 GB)
Configuring Your Storage and I/O Blade
Max.
6
2
6
6
Disk Group 0: 108 GB
HDD 3
(36 GB)
4-3