Notes on performing data migration – HP XP Array Manager Software User Manual

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For example, you can migrate data when your volume performance decreases or your environment
changes. When relocating data based on the results of performance monitoring for volumes being
used by servers and applications, or when migrating data from an old storage system to a newly
set-up storage system, the data in multiple volumes can be migrated to other volumes or THP/Smart
pools.

The source volume can be selected by host or by logical group. The source volume also can be selected
from some of the volumes allocated to a host some of the volumes in a logical group, some of the
volumes in a tier. Migration source volumes can also be selected from volume search results. If a
volume that cannot be migrated is included in the selected volumes, that volume is excluded from
migration and only volumes that can be migrated, will be migrated.

Migration targets are selected from tiers, THP/Smart pools, or resource search results. If THP/Smart
pools are selected, THP/Smart volumes with the same capacity as the migration-source volumes are
automatically created. The existing THP/Smart volumes also can be specified as migration targets.

Note the following:

•

When the migration source and the migration target are selected, individual pairs of migration
source volumes and migration target volumes (or THP/Smart pools) are automatically created.
Although, you can change these pairs, pairs of volumes that cannot be migrated will not be created.

•

During migration, data can still be accessed.

•

When data migration is completed normally, the LDEV ID and host I/O of the migration source
volumes are changed to those of the migration target volumes. The procedure for accessing migrated
data is not changed before or after migration.

•

If linked with HP XP7 Performance Advisor, parity group busy rate for the migration source volume
and migration target volume can be checked.

•

When you create a migration task, you can select whether to delete the migration source volume
after the migration completes. As an alternative, after migrating, you can delete the data of the
source volumes.

•

After volumes are migrated to THP/Smart volumes, unused capacity in the target volumes is returned
to the pool (zero page reclaim) if the zero page reclaim option is on. We recommend that the
migration source volume be deleted if it is a THP/Smart volume and you will not use it. If you do
not delete the migration source volume, we recommend that the zero page of the migration source
volume be discarded after the migration task finishes.

•

You cannot work with volumes (such as copy pair or volume allocation) until the migration tasks
are completed.

You must have a Tiered Storage Manager license registered to perform Data Migration.