VERITAS Volume Manager 3.5 User's Guide - VERITAS Enterprise Administrator (September 2004)

Volume Tasks
Moving, Splitting, and Joining Subdisks
Chapter 4148
Moving, Splitting, and Joining Subdisks
The commands Subdisk Move, Split, and Join, enable you to move
subdisks to other locations within the dynamic group, split subdisks, and
join them back together. The flexibility of moving subdisks, splitting
them, and joining them lets you make best use of your disk space.
• “Moving a Subdisk” on page 148
• “Splitting a Subdisk” on page 150
• “Joining a Subdisk” on page 151
Moving a Subdisk
NOTE You are not allowed to move a subdisk that is part of a boot or system
volume.
The Subdisk Move procedure moves the contents of a volume subdisk
from one disk to another. This is useful for moving portions of a volume
to a different disk for improved performance.
If disk activities are heavily concentrated on one or a small number of
disks in the storage subsystem, it may create bottlenecks. You can use
the Subdisk Move and possibly the Subdisk Split command to spread
out disk accesses more evenly across all the disks to balance the load.
You can use the Subdisk Move command to move all subdisks to
healthier disks. The benefit of moving subdisks instead of copying the
volumes is that you need only enough space on the receiving disks for the
subdisks on the one failed disk, not for entire volumes that may span
multiple disks. Another advantage is that there is no interruption in I/O.
Moving subdisks provides you with a flexible means of making
adjustments in your storage system while it is up and running.
To perform a subdisk move operation:
You can use the Object View window (Disk Groups > Object View) or
the Volume to Disk Mapping window (Disk Groups > Disk/Volume
Map) to view the subdisks and gaps on disks in a disk group. In the Object