Optimization of Volume Configurations
The ETERNUS DX allows for the expansion of volumes and RAID group capacities, migration among RAID groups,
and changing of RAID levels according to changes in the operation load and performance requirements. There
are several expansion functions.
Table 22 Optimization of Volume Configurations
Function/usage
Volume expansion
RAID group expan-
sion
Migration among
RAID groups
Changing the RAID
level
Striping for RAID
groups
RAID Migration
¡
(Adding capacity
during migration)
(*1)
´
¡
¡
´
Logical Device Ex-
pansion
´
¡
´
¡
(Adding drives to
existing RAID
groups)
´
LUN Concatenation
¡
(Concatenating
free spaces)
´
´
´
´
Wide Striping
´
´
´
´
¡
¡
: Possible,
´
: Not possible
*1: For TPVs or FTVs, the capacity cannot be expanded during a migration.
●
Expansion of Volume Capacity
•
RAID Migration (with increased migration destination capacity)
When volume capacity is insufficient, a volume can be moved to a RAID group that has enough free space.
This function is recommended for use when the desired free space is available in the destination.
•
LUN Concatenation
Adds areas of free space to an existing volume to expand its capacity. This uses free space from a RAID group
to efficiently expand the volume.
●
Expansion of RAID Group Capacity
•
Logical Device Expansion
Adds new drives to an existing RAID group to expand the RAID group capacity. This is used to expand the ex-
isting RAID group capacity instead of adding a new RAID group to add the volumes.
●
Migration among RAID Groups
•
RAID Migration
The performance of the current RAID groups may not be satisfactory due to conflicting volumes after perform-
ance requirements have been changed. Use RAID Migration to improve the performance by redistributing the
volumes amongst multiple RAID groups.
●
Changing the RAID Level
•
RAID Migration (to a RAID group with a different RAID level)
Migrating to a RAID group with a different RAID level changes the RAID level of volumes. This is used to con-
vert a given volume to a different RAID level.
•
Logical Device Expansion (and changing RAID levels when adding the new drives)
The RAID level for RAID groups can be changed. Adding drives while changing is also available. This is used to
convert the RAID level of all the volumes belonging to a given RAID group.
2. Basic Functions
Optimization of Volume Configurations
57
FUJITSU Storage ETERNUS DX500 S4/DX600 S4, ETERNUS DX500 S3/DX600 S3 Hybrid Storage Systems Design Guide (Basic)
Copyright 2019 FUJITSU LIMITED
P3AM-7722-25ENZ0
Summary of Contents for ETERNUS DX500 S3/DX600 S3
Page 218: ......