Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

414 Administering cluster functionality
Administering VxVM in cluster environments
Creating volumes with exclusive open access by a node
Note: All shared volumes, including those with exclusive open access, can only be created
on the master node.
When using the
vxassist command to create a volume, you can use the exclusive=on
attribute to specify that the volume may only be opened by one node in the cluster at a
time. For example, to create the mirrored volume volmir in the disk group dskgrp, and
configure it for exclusive open, use the following command:
# vxassist -g dskgrp make volmir 5g layout=mirror exclusive=on
Multiple opens by the same node are also supported. Any attempts by other nodes to open
the volume fail until the final close of the volume by the node that opened it.
Specifying exclusive=off instead means that more than one node in a cluster can open
a volume simultaneously.
Setting exclusive open access to a volume by a node
Note: Exclusive open access on a volume can only be set on the master node. Ensure that
none of the nodes in the cluster have the volume open when setting this attribute.
You can set the
exclusive=on attribute with the vxvol command to specify that an
existing volume may only be opened by one node in the cluster at a time.
For example, to set exclusive open on the volume volmir in the disk group dskgrp, use
the following command:
# vxvol -g dskgrp set exclusive=on volmir
Multiple opens by the same node are also supported. Any attempts by other nodes to open
the volume fail until the final close of the volume by the node that opened it.
Specifying exclusive=off instead means that more than one node in a cluster can open
a volume simultaneously.
Displaying the cluster protocol version
The following command displays the cluster protocol version running on a node:
# vxdctl list
This command produces output similar to the following:
Volboot file
version: 3/1
seqno: 0.19
cluster protocol version: 70
hostid: giga
entries: