When a Domino server hangs, or is unresponsive to a client request, the Lotus Notes client may not fail over to another server in the cluster.
The client will also appear hung with a "lightening bar" in the lower left corner of the screen. This can happen when the Domino server is accepting TCPIP requests
from clients but is unable to process the request. If the Domino server system responds to the client request, the client will NOT attempt failover to the
Domino Cluster server.
Notes Clients hang attempting to connect to a Domino server which is hung.
Lotus Notes clients attempt to connect to the home server. If the system hosting the Domino server responds to a request on port 1352, the client will
wait for the application to respond. If the Domino server is hung, the application response will not happen (even though the TCPIP session response
(SYN ACK) did), causing the client to hang. If the server has crashed rather than hung, 1352 port would not be listening for responses. The Notes client
would attempt to immediately connect to another server in the cluster as no TCPIP response was received from the server.
Domino should have mechanism to understand it's state and allow Notes Client to fail-over to another available Cluster Node, when domino is hung state.