Volume; Figure 9 Volume Concept - Fujitsu ETERNUS DX500 S4/DX600 S4 Design Manual

2. Basic Functions
RAID Functions
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 Rebuild/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 registered in Thin Pro-
visioning 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
Configuration" (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.
The maximum number of volumes that can be created in the ETERNUS DX is 16,384. Volumes can be created
until the combined total for each volume type reaches the maximum number of volumes.
A volume can be expanded or moved if required. Multiple volumes can be concatenated and treated as a single
volume. For availability of expansion, displacement, and concatenation for each volume, refer to
umes of Each Function" (page
FUJITSU Storage ETERNUS DX500 S4/DX600 S4, ETERNUS DX500 S3/DX600 S3 Hybrid Storage Systems Design Guide (Basic)
"Storage Capacity Virtualization" (page
"Automated Storage Tiering" (page
200).
Volume 1
Volume 2
RAID group 1
212).
Copyright 2019 FUJITSU LIMITED
Table 7.
43).
49).
"Assigned CMs" (page
26
105).
"Recommended RAID Group
Volume 3
RAID group 2
"Target Vol-
P3AM-7722-25ENZ0