JGroups TCP over WAN

Chat.java

import org.jgroups.JChannel;
import org.jgroups.Message;
import org.jgroups.ReceiverAdapter;
import org.jgroups.View;
import org.jgroups.util.Util;

public class Chat {

    public static void main(String[] args) throws Exception {
        JChannel ch = new JChannel("tcp.xml");

        ch.setReceiver(new ReceiverAdapter() {
            public void viewAccepted(View new_view) {
                System.out.println("view: " + new_view);
            }

            public void receive(Message msg) {
                System.out.println("<< " + msg.getObject() + " [" + msg.getSrc() + "]");
            }
        });

        ch.connect("ChatCluster");

        for(;;) {
            String line = Util.readStringFromStdin(": ");
            ch.send(null, null, line);
        }
    }

}

commands.sh

# on server1
java -Djgroups.bind_addr=server1 Chat

# on server2
java -Djgroups.bind_addr=server2 Chat

tcp.xml

<config xmlns="urn:org:jgroups"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="urn:org:jgroups http://www.jgroups.org/schema/JGroups-2.8.xsd">
    <TCP bind_port="7800"
	 loopback="true"
         recv_buf_size="${tcp.recv_buf_size:20M}"
         send_buf_size="${tcp.send_buf_size:640K}"
         discard_incompatible_packets="true"
         max_bundle_size="64K"
         max_bundle_timeout="30"
         enable_bundling="true"
         use_send_queues="true"
         sock_conn_timeout="300"

         timer_type="new"
         timer.min_threads="4"
         timer.max_threads="10"
         timer.keep_alive_time="3000"
         timer.queue_max_size="500"
         
         thread_pool.enabled="true"
         thread_pool.min_threads="1"
         thread_pool.max_threads="10"
         thread_pool.keep_alive_time="5000"
         thread_pool.queue_enabled="false"
         thread_pool.queue_max_size="100"
         thread_pool.rejection_policy="discard"

         oob_thread_pool.enabled="true"
         oob_thread_pool.min_threads="1"
         oob_thread_pool.max_threads="8"
         oob_thread_pool.keep_alive_time="5000"
         oob_thread_pool.queue_enabled="false"
         oob_thread_pool.queue_max_size="100"
         oob_thread_pool.rejection_policy="discard"/>
                         
    <TCPPING timeout="3000"
             initial_hosts="${jgroups.tcpping.initial_hosts:server1[7800],server2[7800]}"
             port_range="5"
             num_initial_members="3"/>
    <MERGE2  min_interval="10000"
             max_interval="30000"/>
    <FD_SOCK/>
    <FD timeout="3000" max_tries="3" />
    <VERIFY_SUSPECT timeout="1500"  />
    <BARRIER />
    <pbcast.NAKACK
                   use_mcast_xmit="false" gc_lag="0"
                   retransmit_timeout="300,600,1200,2400,4800"
                   discard_delivered_msgs="true"/>
    <UNICAST timeout="300,600,1200" />
    <pbcast.STABLE stability_delay="1000" desired_avg_gossip="50000"
                   max_bytes="4M"/>
    <pbcast.GMS print_local_addr="true" join_timeout="3000"
                view_bundling="true"/>
    <UFC max_credits="2M"
         min_threshold="0.4"/>
    <MFC max_credits="2M"
         min_threshold="0.4"/>
    <FRAG2 frag_size="60K"  />
    <pbcast.STREAMING_STATE_TRANSFER/>
    <!-- <pbcast.STATE_TRANSFER/> -->  
</config>