reconnect failed after iptables tricks / final

// Client:

import org.zeromq.ZMQ;

import java.util.concurrent.TimeUnit;

import static org.zeromq.ZMQ.DEALER;
import static org.zeromq.ZMQ.SNDMORE;

public class Client {

  public static void main(String[] args) throws InterruptedException {
    ZMQ.Context ctx = ZMQ.context(1);

    ZMQ.Socket client = ctx.socket(DEALER);
    client.connect("tcp://localhost:222");

    long i = 0;
    while (true) {
      // send().
      assert client.send("", SNDMORE);
      assert client.send(("hello" + i), 0);

      // recv().
      byte[] world = client.recv();
      assert world != null;

      i++;
      TimeUnit.SECONDS.sleep(1);
    }
  }
}

// Server:

package org.zeromq;

import static org.zeromq.ZMQ.ROUTER;
import static org.zeromq.ZMQ.SNDMORE;

public class Server {

  public static void main(String[] args) throws InterruptedException {
    ZMQ.Context ctx = ZMQ.context(1);

    ZMQ.Socket server = ctx.socket(ROUTER);
    server.bind("tcp://*:222");

    while (true) {
      // recv().
      byte[] identity = server.recv();
      assert identity != null;

      byte[] div = server.recv();
      assert div != null;

      byte[] hello = server.recv();
      assert hello != null;

      // send().
      assert server.send(identity, SNDMORE);
      assert server.send("world", 0);

      System.out.println("hello/world complete.");
    }
  }
}