Recommended Raid Group Configurations; Figure 107 Drive Combination 1; Figure 108 Drive Combination 2 - Fujitsu ETERNUS AF250 Design Manual

3. Hardware Configurations

Recommended RAID Group Configurations

Recommended RAID Group Configurations
No restrictions on the installation location of drives apply if the same types of drives are used to create RAID
groups.
To improve reliability, the installation location of drives that configure a RAID group must be considered.
Data reliability can be improved by selecting configuration drives that are distributed to controller enclosures
and drive enclosures when a RAID group is created.
For details on the recommended number of drives that configure a RAID group, refer to
■
Mirroring Configuration
RAID1+0(4D+4M) is used in the following examples to explain how drives are installed to configure a mirroring
RAID level.
The drive number is determined by the DE-ID of the enclosure and the slot number in which the drive is instal-
led. Starting from the smallest drive number in the configuration, half of the drives are allocated into one group
and the remaining drives are allocated into the other group. Each drive in the different groups are paired for
mirroring.
Example 1: All drives are installed in a single enclosure

Figure 107 Drive Combination 1

A B
Example 2: Paired drives are installed in two different enclosures

Figure 108 Drive Combination 2

A B
A' B'
C D A' B'
Mirroring
C D
Mirroring
C' D'
FUJITSU Storage ETERNUS AF250 S2, ETERNUS AF250 All-Flash Arrays Design Guide (Basic)
Copyright 2019 FUJITSU LIMITED
CE
C' D'
CE
DE
158
"RAID Group" (page 23).
P3AG-1822-09ENZ0