Veritas Storage Foundation 5.1 SP1 for Oracle RAC Administrator"s Guide (5900-1512, April 2011)

■ Verify that none of the other nodes in the cluster have a port “a” membership
■ Verify that none of the other nodes have any shared disk groups imported
■ Determine why any node that is still running does not have a port “a”
membership
Run the following command to manually seed GAB membership:
# gabconfig -cx
Refer to gabconfig (1M) for more details.
Evaluating VCS I/O fencing ports
I/O Fencing (VxFEN) uses a dedicated port that GAB provides for communication
across nodes in the cluster. You can see this port as port ‘b’ when gabconfig -a
runs on any node in the cluster. The entry corresponding to port ‘b’ in this
membership indicates the existing members in the cluster as viewed by I/O
Fencing.
GAB uses port "a" for maintaining the cluster membership and must be active for
I/O Fencing to start.
To check whether fencing is enabled in a cluster, the ‘-d’ option can be used with
vxfenadm (1M) to display the I/O Fencing mode on each cluster node. Port “b”
membership should be present in the output of gabconfig -a and the output
should list all the nodes in the cluster.
If the GAB ports that are needed for I/O fencing are not up, that is, if port “a” is
not visible in the output of gabconfig -a command, LLT and GAB must be started
on the node.
The following commands can be used to start LLT and GAB respectively:
To start LLT on each node:
# /sbin/init.d/llt start
If LLT is configured correctly on each node, the console output displays:
LLT INFO V-14-1-10009 LLT Protocol available
To start GAB, on each node:
# /sbin/init.d/gab start
If GAB is configured correctly on each node, the console output displays:
GAB INFO V-15-1-20021 GAB available
Prevention and recovery strategies
Evaluating VCS I/O fencing ports
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