HP StorageWorks XP Remote Web Console Software - Manual (Page 8)

NOTE:
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You can also migrate an XP Thin Provisioning virtual volume or an external volume manually.
However, you cannot examine the estimated usage rate after migration because the usage
rate of an external volume cannot be collected.
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OPEN-V volumes, other than the XP Thin Provisioning virtual volumes, might not be displayed
as target volumes. If Inquiry commands are executed to volumes displayed as OPEN-V in the
XP Auto LUN window, the replies from some volumes could be OPEN-V and from other volume
OPEN-0V. You cannot distinguish OPEN-V volumes from OPEN-0V volumes in the LDEV's list
of the XP Auto LUN window. To distinguish between OPEN-V and OPEN-0V volumes, see the
Reports Display dialog box in Remote Web Console.
•
Volume migration between OPEN-V and OPEN-V is permitted, as well as between OPEN-0V
and OPEN-0V. Volume migration between OPEN-V and OPEN-0V is permissible only when
the volumes are XP Thin Provisioning virtual volumes.
•
The system disk cannot be migrated.
•
The quorum disk cannot be migrated.
Before migrating a volume from one parity group to another, you must create a migration plan.
When you create a migration plan, you specify the following:
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A volume for migrating
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The migration destination for the specified volume
To migrate volumes, you execute your migration plan.
Figure 1 (page 8) gives an example of a migration plan as it would be displayed in the Manual
Plan window of XP Auto LUN. In this figure, Source LDEV indicates the volume that should be
migrated. Target LDEV indicates the migration destination for the volume in Source LDEV.
Figure 1 An Example of Migration Plans Displayed in the XP Auto LUN Window
Before you create a migration plan, you must determine which volume should be migrated to which
parity group. When you determine a volume to be migrated, do the following:
1. Check usage rates for volumes.
2. Choose a volume to be migrated from among high-usage volumes.
Figure 2 Usage Rate for a Volume Displayed in the Window
3. After determining a migration destination, find fast parity groups (that is, fast hard disk drives).
Next, you should choose a low-usage parity group from the fast parity groups.
To find fast hard disk drives, display the XP Auto LUN window and check classes ( Figure 3 (page
9) ). Classes indicate disk access speed for parity groups. Fastest parity groups (or groups of
fastest disks) belong to class A. Parity groups in class B are not as fast as parity groups in class
8 About XP Auto LUN Operations