For details on the functions that can be executed simultaneously and the number of the process that can be
processed simultaneously, refer to
"Combinations of Functions That Are Available for Simultaneous Executions"
.
•
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.
-
Using the same interface speed is recommended when using SSDs.
-
When installing SSDs in high-density drive enclosures, using SSDs that have the same drive enclosure
transfer speed is recommended.
•
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.
LUN Concatenation
LUN Concatenation is a function that is used to add new area to a volume and so expand the volume capacity
available to the server. This function enables the reuse of leftover free area in a RAID group and can be used to
solve capacity shortages.
Unused areas, which may be either part or all of a RAID group, are used to create new volumes that are then
added together (concatenated) to form a single large volume.
The capacity can be expanded during an operation.
Figure 35 LUN Concatenation
LUN0
LUN2
LUN1
RAID5 (3D+1P) 300GB x 4
RAID5 (3D+1P) 300GB x 4
LUN0
LUN2
LUN1
Unused area
LUN0
LUN2
RAID5 (3D+1P) 300GB x 4
RAID5 (3D+1P) 300GB x 4
LUN0
LUN2
LUN1
Concatenates an
unused area into
LUN2
Concatenation
LUN Concatenation is a function to expand a volume capacity by concatenating volumes.
Up to 16 volumes with a minimum capacity of 1GB can be concatenated.
2. Basic Functions
Optimization of Volume Configurations
62
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
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