Raid Migration - Fujitsu ETERNUS DX80 S2 User Manual

Chapter 3 Setup
3.7 Optimizing Volume Configurations
3.7.1

RAID Migration

RAID Migration is a function that transfers a volume to a different RAID group while guaranteeing the
integrity of the data. By using RAID Migration, RAID groups and volumes can be hot switched. This allows easy
redistribution of volumes among RAID groups in response to customer needs. The redistribution of volumes
and reconfiguration of RAID groups (e.g. changing the RAID level from RAID5 to RAID1+0) can be performed
while the system is running.
This section describes the restrictions and notes on using RAID Migration.
For details on the RAID Migration procedure, refer to "ETERNUS Web GUI User's Guide" or "ETERNUS CLI User's
Guide".
• Volumes can be specified as a target for RAID Migration.
• The total number of RAID Migration, Flexible Tier Migration, TPV balancing, and FTRP balancing processes
that can be performed at the same time is 32.
• The total capacity for RAID Migration, Flexible Tier Migration, TPV balancing, and FTRP balancing processes
that can be performed in at the same time is 128TB.
• The volume types that can be migrated are Standard/Open, TPV, FTV, and WSV. RAID groups, TPPs, FTRPs,
and WSVs can be selected as the RAID Migration destination. If a volume is migrated to a RAID group, it
becomes a Standard/Open volume. If a volume is migrated to a TPP, it becomes a TPV. If a volume is
migrated to an FTRP, it becomes an FTV. If a volume is migrated to a WSV, it becomes a WSV.
• Capacity expansion can be performed at the same time as RAID migration when the RAID Migration source
is a RAID group (Standard/Open) or a WSV and the RAID Migration destination is also a RAID group
(Standard/Open) or a WSV.
Also note that when the RAID Migration source and destination are both WSVs, the number of concatena-
tions for existing RAID groups can be changed.
• Capacity expansion cannot be performed at the same time as RAID migration when the RAID Migration
source is a TPV or an FTV or when the RAID Migration destination is a TPP or an FTRP.
To expand the capacity, use the capacity expansion function of a TPV or an FTV before RAID Migration starts
or after RAID Migration is complete.
• When the RAID Migration destination is a TPP or an FTRP, whether Zero Reclamation is performed after
RAID Migration is complete can be set.
• RAID Migration cannot be performed for volumes that are undergoing Zero Reclamation.
• RAID Migration cannot be performed when the source volume type is "SDV" or "SDPV".
• Select RAID groups under any of the following conditions for the RAID Migration destination:
- The RAID group is not registered as the REC disk buffer.
- The RAID group has an unused area that is more than the capacity of the RAID Migration source
volume.
• TPPs or FTRPs under any of the following conditions cannot be selected as the RAID Migration destination.
- When the capacity of TPP or FTRP is less than the capacity of the RAID Migration source volume (*1)
- When the capacity of the RAID Migration source volume is equal to or larger than the maximum
capacity of TPP for each model (*2)
*1: When the RAID Migration source is a TPV or an FTV, the RAID Migration source volume capacity indicates the
used capacity (physical capacity allocated from a TPP or an FTRP).
*2: This is the total capacity of the TPPs and the FTRPs in the ETERNUS DX Disk storage system.
• RAID levels that are supported by the ETERNUS DX Disk storage system can be set for the source and
destination RAID groups.
• The final volume number (LUN) will be the same as the initial volume number, and from the point of view
of the server, pre-migration, migrating and post-migration volumes are accessed indistinguishably.
ETERNUS DX80 S2/DX90 S2 Disk storage system User's Guide -Operation-
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Copyright 2013 FUJITSU LIMITED P3AM-4842-12ENZ0