Using Serviceguard Extension for RAC, 6th Edition, April 2008

The following message is displayed:
Activated volume group in shared mode.
This node is the Server.
When the same command is entered on the second node, the following message is
displayed:
Activated volume group in shared mode.
This node is a Client.
NOTE: Do not share volume groups that are not part of the RAC configuration unless
shared access is controlled.
Deactivating a Shared Volume Group
Issue the following command from each node to deactivate the shared volume group:
# vgchange -a n /dev/vg_ops
Remember that volume groups remain shareable even when nodes enter and leave the
cluster.
NOTE: If you wish to change the capacity of a volume group at a later time, you must
deactivate and unshare the volume group first. If you add disks, you must specify the
appropriate physical volume group name and make sure the /etc/lvmpvg file is
correctly updated on both nodes.
Making Offline Changes to Shared Volume Groups
You may need to change the volume group configuration of RAC shared logical volumes
to add capacity to the data files or to add log files. No configuration changes are allowed
on shared LVM volume groups while they are activated. The volume group must be
deactivated first on all nodes, and marked as non-shareable. Use the following procedure
(examples assume the volume group is being shared by node 1 and node 2, and they
use the volume group vg_ops):
1. Ensure that the Oracle RAC database is not active on either node.
2. From node 2, use the vgchange command to deactivate the volume group:
# vgchange -a n /dev/vg_ops
3. From node 2, use the vgexport command to export the volume group:
# vgexport -m /tmp/vg_ops.map.old /dev/vg_ops
This dissociates the volume group from node 2.
4. From node 1, use the vgchange command to deactivate the volume group:
# vgchange -a n /dev/vg_ops
5. Use the vgchange command to mark the volume group as unshareable:
# vgchange -S n -c n /dev/vg_ops
Managing the Shared Storage 153