You can move a virtual disk (VDisk) to a new I/O group
to manually balance the workload across the nodes in the cluster.
This task assumes that you have already launched the SAN Volume Controller Console.
Attention: This is a disruptive procedure. Access
to the VDisk is lost while you follow this procedure. Under no circumstances
should VDisks be moved to an offline I/O group. You must ensure that
the I/O group is online before moving the VDisks to avoid data loss.
Complete
the following steps to move a single VDisk:
- Quiesce all I/O operations for the VDisk. You might have
to determine the hosts that are using this VDisk.
- Update the multipathing device driver configuration to
remove all device identifiers that are presented by the VDisk you
intend to move. If you are using the system device driver (SDD), the
device identifiers are referred to as virtual paths (vpaths).
Attention: Failure to perform this step can result
in data corruption.
- Stop and delete all FlashCopy® mappings,
Metro Mirror, or Global Mirror relationships that use this VDisk.
To check if the VDisk is part of a mapping or relationship, perform
the following steps:
- Click in the portfolio.
The Viewing Virtual Disks panel is displayed.
- Click on the name of the VDisk that you want to migrate.
The View VDisk General Details panel is displayed.
- Look for the FlashCopy Map Count and Relationship
ID fields. If these fields are not blank or contain zeros, the
VDisk is part of a mapping or relationship.
- Click Close to close the panel.
- Move the VDisk by selecting the VDisk from the Viewing
Virtual Disks panel and select Modify a VDisk from
the task list and click Go. The Modifying Virtual Disk panel
is displayed.
- Select the new I/O group from the I/O Group list
and click OK.
- Follow your multipathing device drivers instructions for
discovering new device identifiers. For example, if
you are using SDD, see the IBM® System Storage® Multipath
Subsystem Device Driver User's
Guide and
follow the instructions for discovering vpaths.