When conencting Log Concentrators to ESA I am getting:
Failed to connect to x.x.x.x:50005 org.apache.mina.core.RuntimeIoException: Failed to create a new instance of org.apache.mina.transport.socket.nio.NioProcessor:null
The Packet Decoders can connect with no problem.
Turns out the issue was resolving the Concentrators to the Broker. Adding the hostname (not FQDN) into the host file /etc/hosts corrected this issue.
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