RMI Doesn't Work Over Firewall

Question

Hi,I need urgent help!!! I am writing a RMI server which will be hosted behind the firewall and the client could be anyone. I started my RMI server but I have problem connecting to it. Here's my codes:
If you look at the Client.java class, my code got as far as:
Registry reg = LocateRegistry.getRegistry("216.16.45.33", 2001);
I could get the registry but the lookup of "MyServer" failed. I encounter, the "java.rmi.ConnectException: Connection refused" at the Client side.
More info:
I am using Linksys router and I have already set the router to forward all traffics at port 2001 and 2999 to go to the computer that hosts the RMI server. Can someone point me to the right direction? THANKS GUYS!!!!
----FixedPortRMISocketFactory.java----
import java.rmi.server.RMISocketFactory;
import java.net.Socket;
import java.net.ServerSocket;
import java.io.IOException;
public class FixedPortRMISocketFactory extends RMISocketFactory {     
public ServerSocket createServerSocket(int port) throws IOException {
port = (port == 0 ? 2999: port); //use some arbitrary fixed port.
return new ServerSocket(port);
public Socket createSocket(String host, int port) throws IOException {          
return new Socket(host, port);
----End of MyRMIServer .java----
----MyRMIServer .java----
import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;
import java.rmi.RMISecurityManager;
import java.rmi.server.RMISocketFactory;
import java.rmi.Naming;
import java.rmi.registry.Registry;
import java.rmi.registry.LocateRegistry;
public class MyRMIServer extends UnicastRemoteObject implements HelloWorldIf {
public boolean helloWorld() throws RemoteException {
return "hello world";
public static void main(String[] args) {
if (System.getSecurityManager() == null) {
// Create and install the security manager
System.setProperty("java.security.policy","java.policy");
System.setSecurityManager(new RMISecurityManager());
try {     
RMISocketFactory.setSocketFactory(new FixedPortRMISocketFactory());
String host = "rmi://216.16.45.33:2001 + "/MyServer";
MyRMIServer server = new MyRMIServer ();
Registry reg = LocateRegistry.createRegistry(2001);
Naming.rebind(host, server);
System.out.println("MyServerbound on localhost");
} catch (Exception e) {
System.out.println("Error trying to bind MyServer.");
e.printStackTrace();
----End of MyRMIServer .java----
----Client .java----
import java.rmi.*;
import java.rmi.registry.Registry;
import java.rmi.registry.LocateRegistry;
import java.rmi.server.RMISocketFactory;
public class Client {
public static void main(String[] args) {
if (System.getSecurityManager() == null) {
System.setProperty("java.security.policy","java.policy");
System.setSecurityManager(new RMISecurityManager());
try {
Registry reg = LocateRegistry.getRegistry("216.16.45.33", 2001);          
HelloWorldIf server = (HelloWorldIf)reg.lookup("MyServer");
System.out.println("****String got from server: " + server.helloWorld());
} catch (Exception e) {
System.out.println("****Exception looking for server.");
----End of Client .java----
----java.policy----
grant {
permission java.security.AllPermission;
----End of java.policy----

Answer 1

On what platform (Linux or windows) your server is running?
And more important, what IP address this server has?
When it tries to bind object to IP that is not set to this machine, then it fails. RMI server does not say any error or something...
I had the same problem. I added second interface (linux command):
ifconfig eth0 xxx.xxx.xxx.xxx
where xxx.xxx.xxx.xxx is my public IP.