I am running two jgroup channel as below in two linux machines. Node 1 :- java -Djgroups.bind_addr=192.168.1.119 -cp ./jgroups-3.0.14.Final.jar:./$JAVA_HOME: SimpleChat public class SimpleChat extends ReceiverAdapter { JChannel channel; String user_name=System.getProperty("user.name", "n/a"); final List<String> state=new LinkedList<String>(); public void viewAccepted(View new_view) { System.out.println("This is from @ADMIN@ ** view: " + new_view); } channel=new JChannel(); channel.setReceiver(this); channel.connect("ChatCluster"); channel.getState(null, 10000); Node 2 : java -Djgroups.bind_addr=192.168.1.119 -cp ./jgroups-3.0.14.Final.jar:./$JAVA_HOME: SimpleChat1 channel=new JChannel(); channel.connect("ChatCluster"); McastReceiverTest and McastSenderTest works fine also i tried -Djgroups.bind_port=8801 -Djava.net.preferIPv4Stack=true.But not forming cluster. in log :- dmin-PC-38687: dropped message 6 from root-57050 (sender not in table [admin-PC-38687, localhost-53705] ), view= [admin-PC-38687|1] [admin-PC-38687, localhost-53705] Between linux and windows the sample woks fine.I used bind_addr for this. When new member join,viewAccepted() will be invoked. In linux also using this ,even though not forming cluster.(not invoking viewAccepted())