In the following figure, Node C was placed in the kernel debugger too long so it appears as a hung node. Nodes A and B decided that Node C's state was LEFTCLUSTER.
To recover from this situation, you would need to do the following:
Shut down Node C, and bring it back up.
If Node C fails to join the cluster and remains in the LEFTCLUSTER state after being shut down and coming back up, start up the Cluster Admin on Node A or B. Use Mark Node Down from the Tools pull-down menu in the CF portion of the GUI to mark Node C DOWN.
The node should successfully join the cluster.