HP XP Array Manager Software - Manual (Page 114)

• Migrating data to a different storage system , page 120
Notes on performing data migration
The number of volumes that are candidates for migration target volumes are narrowed down and
displayed when selecting a migration target volume. If you want to display all the volumes, in the
migration.properties file on the Device Manager server set a value for the
migration.plan.candidateVolumeCountLimit property.
For details on the properties file, refer to the HP P9000 Command View Advanced Edition Suite
Software Administrator Guide. To avoid insufficient memory, we recommend that you use the default.
The maximum number of volumes that can be displayed as migration target candidates is 2,000
volumes. Exceeding this value will produce an error.
The maximum number of volumes that can be displayed as migration source candidates is 500
volumes. Exceeding this value will produce an error.
Data migration tasks take a long time from start of execution to completion. This might affect the
performance of access from hosts to target volumes. To avoid executing such tasks while the access
frequency is high, check the time required to complete the tasks and set a task execution schedule
before registering the tasks. Actual required time might differ considerably in cases such as performing
migration for the first time, migrating a volume smaller than 170 GB, or migrating many volumes at
the same time.
When storage systems or hosts are under a heavy load, migration might fail. In this case, reduce the
load on the storage systems, and then perform data migration again.
If data migration fails, the integrity of data on the migration target cannot be ensured. Therefore, data
migration must be restarted.
If a data migration fails, and operations for the migration target such as re-execution of data migration
and volume allocation cannot be performed, the storage system must be refreshed.
Related topics
• About data migration , page 113
• Migrating data for volume performance , page 119
• Migrating data to a different storage system , page 120
Conditions for data migration
Data migration conditions include conditions that apply to all volumes (volume migration requirements),
and conditions that depend on the type of volume (volume migration requirements related to volume
type).
For some volumes, when you try to select those volumes as migration-source volumes, the reasons
why they cannot be selected as migration-source volumes are displayed on-screen.
Volume migration requirements
All volumes for which data migration is to be performed must meet the following conditions:
• Migration-source and migration-target volumes exist within one of the following storage systems
(chassis):
• HP P9500
• XP24000/XP20000
• XP12000/XP10000/SVS200
Managing storage resources in a SAN environment 114