Recommended Raid Group Configuration - Fujitsu ETERNUS DX S5 Series Design Manual

6. Hardware Configurations

Recommended RAID Group Configuration

Recommended RAID Group Configuration
In an ETERNUS DX, a controller enclosure is connected to drive enclosures with multiple paths.
For the ETERNUS DX60 S5/DX100 S5/DX200 S5
•
There are no restrictions on the installation locations of drives that configure a RAID group.
To improve reliability, the installation location of drives that configure a RAID group must be considered.
Data reliability can be improved by selecting configured 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
37).
• For the ETERNUS DX500 S5/DX600 S5/DX900 S5
There are no restrictions on the installation locations of drives that configure a RAID group.
The ETERNUS DX500 S5/DX600 S5 has four groups of paths and the ETERNUS DX900 S5 has eight groups of
paths.
Data reliability can be improved by taking the path groups into consideration when distributing drives to
configure a RAID group.
Data reliability when drive enclosures fail can be improved by selecting configuration drives that are
distributed to a larger number of drive enclosures even within the same path group.
Note
• To create a RAID group manually, keep the recommended placement in mind for the configured drive
that is described here.
• For details on the recommended number of drives that configure a RAID group, refer to
(page 37).
Caution
When selecting a RAID level such as RAID1 and RAID1+0 that configure mirroring within a RAID group,
reliability is improved by installing paired drives in different drive enclosures that belong to two or more
separate path groups.
■
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 IDs (DE-ID and CE-ID) of the enclosure and the slot number in which the
drive is installed. 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.
295
"RAID Group" (page
"RAID Group"
Design Guide