org.jgroups.protocols.TCP - [warn] JGRP000006: 10.244.15.191:7800: failed accepting connection from peer Socket[addr=/10.244.70.136,port=35305,localport=7800]: java.lang.NullPointerException: Cannot invoke "java.util.concurrent.BlockingQueue.offer(Object)" because "this.queue" is null
I believe the issues are here, where the ack tries to be sent before connection is started (and thus queue has not been created):
https://github.com/belaban/JGroups/blob/master/src/org/jgroups/blocks/cs/TcpServer.java#L127
https://github.com/belaban/JGroups/blob/master/src/org/jgroups/blocks/cs/TcpServer.java#L135
Is it safe to start connection before sending ack?