what does this mean?

[kuvera]

Could somebody please explain to me this exception I get on the client side?

org.jboss.remoting.CannotConnectException: Can not get connection to server. Problem establishing socket connection for locator - InvokerLocator [socket://127.0.0.1:3873/]
 at org.jboss.remoting.transport.socket.MicroSocketClientInvoker.transport(MicroSocketClientInvoker.java:319)
 at org.jboss.remoting.MicroRemoteClientInvoker.invoke(MicroRemoteClientInvoker.java:116)
 at org.jboss.remoting.Client.invoke(Client.java:612)
 [several more omitted for brevity]
Caused by: java.net.ConnectException: Connection refused: connect
 at java.net.PlainSocketImpl.socketConnect(Native Method)
 at java.net.PlainSocketImpl.doConnect(Unknown Source)
 at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
 [several more omitted for brevity]

I use EJB3. Does it mean I also need to open port 3873 on the server? (currently 1098,1099,4444 are open). And why does it refer to localhost, when I did set java.rmi.server.hostname to the server external IP? (The server is bound to 0.0.0.0 because binding it to the external IP causes many exceptions) (4.2.0 CR2)

[rino_salvade]

EJB3 uses standardwise JBoss Remoting and by default the socket communication on port 3873. This is configured in $JBOSS_HOME/server/default/deploy/ejb3.deployer/META_INF/jboss-service.xml.
So I assume whatever you have set in jva.rmi.server.hostname has no impact at all.
And yes, you need to open up this port.

[kuvera]

Thank you.
I admit I have a hard time understanding the "UsingJBossBehindAFirewall" wiki. It refers to services, which I know little about (users guide is too much for my head). Do I need "RmiPort" (1098)? Do I need jrmpInvoker or pooledInvoker (4444/4445), or both? I don't have a clue.
Do these ports need to be open on the client side? Do they have inbound or outbound traffic on both sides? About these issues I could not find information I could understand. :(