Figure 27 Logical Device Expansion (When Changing The Raid Level) - Fujitsu ETERNUS DX60 S4 Design Manual

1. Function
Optimization of Volume Configurations
Change the RAID levels (from RAID5(3D+1P) g RAID1+0(4D+4M))
•

Figure 27 Logical Device Expansion (When Changing the RAID Level)

RAID5 (3D+1P) 600GB x 4
Unused 600GB x 4
LDE works in terms of RAID group units. If a target RAID group contains multiple volumes, all of the data in the
volumes is automatically redistributed when LDE is performed. Note that LDE cannot be performed if it causes
the number of data drives to be reduced in the RAID group.
In addition, LDE cannot be performed for RAID groups in which the following conditions apply.
RAID groups that belong to TPPs
•
RAID groups in which WSVs are registered
•
• RAID groups that are configured with RAID5+0 or RAID6-FR
LDE may not be available when other functions are being used in the ETERNUS DX or the target RAID group.
For details on the functions that can be executed simultaneously and the number of the process that can be
processed simultaneously, refer to
(page 146).
If drives of different capacities exist in a RAID group that is to be expanded while adding drives, the small-
•
est capacity becomes the standard for the RAID group after expansion, and all other drives are regarded as
having the same capacity as the smallest drive. In this case, the remaining drive space is not used.
If drives of different rotational speeds exist in a RAID group, the access performance of the RAID group is
reduced by the slower drives.
Since the data cannot be recovered after the failure of LDE, back up all the data of the volumes in the target
•
RAID group to another area before performing LDE.
If configuring RAID groups with Advanced Format drives, the write performance may be reduced when ac-
•
cessing volumes created in the relevant RAID group from an OS or an application that does not support Ad-
vanced Format.
FUJITSU Storage ETERNUS DX60 S4, ETERNUS DX60 S3 Hybrid Storage Systems Design Guide (Basic)
LUN0
Expansion
Expands the capacity by
adding four drives and
changes the RAID level
"Combinations of Functions That Are Available for Simultaneous Executions"
Copyright 2019 FUJITSU LIMITED
RAID1+0 (4D+4M) 600GB x 8
LUN0
LUN0
46
P3AM-8992-14ENZ0