Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

Note: The default policy ensures that a small number of disk groups can be merged
successfully between a set of machines. However, where disk groups are merged
automatically using failover mechanisms, select ranges that avoid overlap.
To view the base minor number for an existing disk group, use the vxprint
command as shown in the following examples for the disk group, mydg:
# vxprint -l mydg | grep minors
minors: >=45000
# vxprint -g mydg -m | egrep base_minor
base_minor=45000
To set a base volume device minor number for a disk group that is being created,
use the following command:
# vxdg init diskgroup minor=base_minor disk_access_name ...
For example, the following command creates the disk group, newdg, that includes
the specified disks, and has a base minor number of 30000:
# vxdg init newdg minor=30000 c1d0t0 c1t1d0
If a disk group already exists, you can use the vxdg reminor command to change
its base minor number:
# vxdg -g diskgroup reminor new_base_minor
For example, the following command changes the base minor number to 30000
for the disk group, mydg:
# vxdg -g mydg reminor 30000
If a volume is open, its old device number remains in effect until the system is
rebooted or until the disk group is deported and re-imported. If you close the open
volume, you can run vxdg reminor again to allow the renumbering to take effect
without rebooting or re-importing.
An example of where it is necessary to change the base minor number is for a
cluster-shareable disk group. The volumes in a shared disk group must have the
same minor number on all the nodes. If there is a conflict between the minor
numbers when a node attempts to join the cluster, the join fails. You can use the
reminor operation on the nodes that are in the cluster to resolve the conflict. In
a cluster where more than one node is joined, use a base minor number which
does not conflict on any node.
Creating and administering disk groups
Moving disk groups between systems
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