2.
Basic Functions
RAID Functions
RAID level
RAID6
RAID6-FR
*1: D = Data, M = Mirror, P = Parity, HS = Hot Spare
•
Sequential access performance hardly varies with the number of drives for the RAID group.
•
Random access performance tends to be proportional to the number of drives for the RAID
group.
•
Use of higher capacity drives will increase the time required for the drive rebuild process to
complete.
For RAID5, RAID5+0, and RAID6, ensure that a single RAID group is not being configured with
•
too many drives.
If the number of drives increases, the time to perform data restoration from parities and Re-
build/Copyback when a drive fails also increases.
For details on the recommended number of drives, refer to
The RAID level that can be registered in REC Disk Buffers is RAID1+0. The drive configurations
•
that can be registered in REC Disk Buffers is 2D+2M or 4D+4M.
For details on the Thin Provisioning function and the RAID configurations that can be regis-
tered in Thin Provisioning Pools, refer to
For details on the Flexible Tier functions and the RAID configurations that can be registered in
Flexible Tier Pools, refer to
An assigned CM is allocated to each RAID group. For details, refer to
For the installation locations of the drives that configure the RAID group, refer to
RAID Group Configurations" (page
Volume
This section explains volumes.
Logical drive areas in RAID groups are called volumes.
A volume is the basic RAID unit that can be recognized by the server.
Figure 9 Volume Concept
A volume may be up to 128TB. However, the maximum capacity of volume varies depending on the
OS of the server.
Fujitsu Storage ETERNUS DX100 S4/DX200 S4, ETERNUS DX100 S3/DX200 S3 Hybrid Storage Systems Design Guide (Basic)
Number of configu-
Recommended number of drives (*1)
ration drives
5 to 16
5(3D+2P), 6(4D+2P), 7(5D+2P)
11 to 31
17 ((6D+2P) ´2+1HS)
"Automated Storage Tiering" (page
192).
Volume 1
Volume 2
RAID group 1
Copyright 2023 Fujitsu Limited
Table
"Storage Capacity Virtualization" (page
49).
26
7.
42).
"Assigned CMs" (page
"Recommended
Volume 3
RAID group 2
P3AM-7642-32ENZ0
104).