Note You need a Veritas FlashSnapTM license to use this feature.
There are several circumstances under which you might want to reorganize the contents of your existing disk groups:
You can use either the Veritas Enterprise Administrator (VEA) or the vxdg
command to reorganize your disk groups. For more information about using the graphical user interface, see the Veritas Enterprise Administrator User's Guide and VEA online help. This section describes how to use the vxdg
command.
The vxdg
command provides the following operations for reorganizing disk groups:
move
—moves a self-contained set of VxVM objects between imported disk groups. This operation fails if it would remove all the disks from the source disk group. Volume states are preserved across the move. The move
operation is illustrated in Disk group move operation.
Disk group move operation
Click the thumbnail above to view full-sized image.
split
—removes a self-contained set of VxVM objects from an imported disk group, and moves them to a newly created target disk group. This operation fails if it would remove all the disks from the source disk group, or if an imported disk group exists with the same name as the target disk group. An existing deported disk group is destroyed if it has the same name as the target disk group (as is the case for the vxdg
init
command). The split
operation is illustrated in Disk group split operation.
Disk group split operation
Click the thumbnail above to view full-sized image.
join
—removes all VxVM objects from an imported disk group and moves them to an imported target disk group. The source disk group is removed when the join is complete. The join
operation is illustrated in Disk group join operation.
Disk group join operation
Click the thumbnail above to view full-sized image.
These operations are performed on VxVM objects such as disks or top-level volumes, and include all component objects such as sub-volumes, plexes and subdisks. The objects to be moved must be self-contained, meaning that the disks that are moved must not contain any other objects that are not intended for the move.
If you specify one or more disks to be moved, all VxVM objects on the disks are moved. You can use the -o
expand
option to ensure that vxdg
moves all disks on which the specified objects are configured. Take care when doing this as the result may not always be what you expect. You can use the listmove
operation with vxdg
to help you establish what is the self-contained set of objects that corresponds to a specified set of objects.
Caution Before moving volumes between disk groups, stop all applications that are accessing the volumes, and unmount all file systems that are configured on these volumes.
If the system crashes or a hardware subsystem fails, VxVM attempts to complete or reverse an incomplete disk group reconfiguration when the system is restarted or the hardware subsystem is repaired, depending on how far the reconfiguration had progressed. If one of the disk groups is no longer available because it has been imported by another host or because it no longer exists, you must recover the disk group manually as described in the section "Recovery from Incomplete Disk Group Moves" in the chapter "Recovery from Hardware Failure" of the Veritas Volume Manager Troubleshooting Guide.