CWOBJ7211=CWOBJ7211I: As a result of a heartbeat (view heartbeat type) from leader {0} for core group {1} with member list {2}, the server {3} is being removed from the core group view.
Explanation
The server was removed from the core group because it was deemed unreachable.
User response
Investigate whether the becomes network accessible to the server sending the heartbeat, and if not, restart the server and if possible address accessibility.