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

Writing a new UDID to a disk
You can use the following command to update the unique disk identifier (UDID)
for one or more disks. This is useful when building a new LUN from space
previously used by a deleted LUN, for example.
# vxdisk [-f] [-g diskgroup ] updateudid disk ...
This command uses the current value of the UDID that is stored in the Device
Discovery Layer (DDL) database to correct the value in the private region. The -f
option must be specified if VxVM has not set the udid_mismatch flag for a disk.
For example, the following command updates the UDIDs for the disks c2t66d0
and c2t67d0:
# vxdisk updateudid c2t66d0 c2t67d0
Importing a disk group containing cloned disks
By default, disks on which the udid_mismatch flag or the clone_disk flag has
been set are not imported by the vxdg import command unless all disks in the
disk group have at least one of these flags set, and no two of the disks have the
same UDID. You can then import the cloned disks by specifying the -o
useclonedev=on option to the vxdg import command, as shown in this example:
# vxdg -o useclonedev=on [-o updateid] import mydg
This form of the command allows only cloned disks to be imported. All non-cloned
disks remain unimported.
If the clone_disk flag is set on a disk, this indicates the disk was previously
imported into a disk group with the udid_mismatch flag set.
The -o updateid option can be specified to write new identification attributes to
the disks, and to set the clone_disk flag on the disks. (The vxdisk set clone=on
command can also be used to set the flag.) However, the import fails if multiple
copies of one or more cloned disks exist. In this case, you can use the following
command to tag all the disks in the disk group that are to be imported:
# vxdisk [-g diskgroup ] settag tagname disk ...
where tagname is a string of up to 128 characters, not including spaces or tabs.
For example, the following command sets the tag,, on several disks that are to be
imported together:
# vxdisk settag my_tagged_disks c2t66d0 c2t67d0
Creating and administering disk groups
Handling cloned disks with duplicated identifiers
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