Up to 16 volumes with a minimum capacity of 1GB can be concatenated.
Volumes can be concatenated up to 128TB (up to 1TB for ODX Buffer volumes).
Concatenation can be performed regardless of the RAID levels of the concatenation source volume and the
concatenation destination volume.
For SSDs and SEDs, the drives for the concatenation source and destination volumes must be the same type (SSD
or SED).
From a performance perspective, using RAID groups with the same RAID level and the same drives (type and
capacity) is recommended as the concatenation source.
The same key group setting is recommended for the RAID group to which the concatenation source volumes
belong and the RAID group to which the concatenation destination volumes belong if the RAID groups are
configured with SED SSDs.
A concatenated volume can be used as an OPC, EC, or QuickOPC copy source or copy destination. It can also be
used as a SnapOPC/ copy source.
The LUN number stays the same before and after the concatenation. Because the server-side LUNs are not
changed, an OS reboot is not required. Data can be accessed from the host in the same way regardless of the
concatenation status (before, during, or after concatenation). However, the recognition methods of the volume
capacity expansion vary depending on the OS types.
Figure 32
LUN Concatenation (Volume Concatenation)
10GB
20GB
30GB
+
+
60GB
Unused area
Concatenation
Only Standard type volumes can be used for LUN Concatenation. The encryption status of a concatenated volume
is the same status as a volume that is to be concatenated.
LUN Concatenation may not be available when other functions are being used in the ETERNUS AF or the target
volume.
For details on the functions that can be executed simultaneously, refer to
"Combinations of Functions That Are
Available for Simultaneous Executions" (page 201)
.
Caution
•
It is recommended that the data on the volumes that are to be concatenated be backed up first.
•
Refer to the applicable OS and file system documentation before dynamically expanding the volume
capacity because expanded volumes may not be recognized by some types and versions of server-side
platforms (OSs).
•
When a volume that is using ETERNUS SF AdvancedCopy Manager to run backups is expanded via LUN
Concatenation, the volume will need to be registered with ETERNUS SF AdvancedCopy Manager again.
2. Basic Functions
Optimization of Volume Configurations
67
Design Guide
Summary of Contents for ETERNUS AF S3 Series
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