If you are having communications issues, you can see some of the internal communication messages that are generated by iCluster behind the scenes to assist in problem resolution. Just create a new message queue on the node that appears to be having the problem called DMKMSGQ in the iCluster product library (almost always ICLUSTER).
CRTMSGQ MSGQ(ICLUSTER/DMKMSGQ) MSGQFULL (*WRAP)
Then after a period of time, use DSPMSGQ DMKMSGQ to display the messages and send them to support. You can keep the message queue active if you like or delete it once the problem is solved.
Here is the entire list of steps to obtain and review iCluster communication issues: