System log shows "Cluster is not Quorate Refusing connection" on a two/four node Red Hat Enterprise Linux 5 cluster?

Issue

• The following error is being logged in the messages file every second

  ccsd[4439]: Cluster is not quorate.  Refusing connection.  
  ccsd[4439]: Error while processing connect: Connection refused 
  

• One node is connected to cluster but others are not. Throws above error messages.

• Cluster has lost token and it is unable to regain quorum. Why cluster could not quorate?
• The service status & clustat command sees rgmanager is not functional, after the servers hanging we notice the node 2 unable to join the cluster group and logs above messages.
• Cluster Servers not quorate and unable to join cluster. The /var/log/messages shows Cluster is not quorate. Refusing connection events logged.
• Our 2 node cluster is not able to quorate and we're not able to bring up cluster service.