Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

Any volumes on the device should only be grown after the LUN itself has first
been grown.
Resizing should only be performed on LUNs that preserve data. Consult the array
documentation to verify that data preservation is supported and has been qualified.
The operation also requires that only storage at the end of the LUN is affected.
Data at the beginning of the LUN must not be altered. No attempt is made to verify
the validity of pre-existing data on the LUN. The operation should be performed
on the host where the disk group is imported (or on the master node for a
cluster-shared disk group).
Resizing of LUNs that are not part of a disk group is not supported. It is not possible
to resize LUNs that are in the boot disk group (aliased as bootdg), in a deported
disk group, or that are offline, uninitialized, being reinitialized, or in an error
state.
Warning: Do not perform this operation when replacing a physical disk with a disk
of a different size as data is not preserved.
Before shrinking a LUN, first shrink any volumes on the LUN or more those
volumes off the LUN. Then, resize the device using vxdisk resize. Finally, resize
the LUN itself using the storage array's management utilities. By default, the
resize fails if any subdisks would be disabled as a result of their being removed
in whole or in part during a shrink operation.
If the device that is being resized has the only valid configuration copy for a disk
group, the -f option may be specified to forcibly resize the device.
Resizing a device that contains the only valid configuration copy for a disk group
can result in data loss if a system crash occurs during the resize.
Resizing a virtual disk device is a non-transactional operation outside the control
of VxVM. This means that the resize command may have to be re-issued following
a system crash. In addition, a system crash may leave the private region on the
device in an unusable state. If this occurs, the disk must be reinitialized, reattached
to the disk group, and its data resynchronized or recovered from a backup.
Removing disks
You must disable a disk group before you can remove the last disk in that group.
See “Disabling a disk group” on page 240.
As an alternative to disabling the disk group, you can destroy the disk group.
See “Destroying a disk group” on page 240.
Administering disks
Removing disks
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