I tried both suggestions, and unfortuanly stillhave the problem I change to "true" the UDP loopback option on cluster-service.xml and on deploy\tc5-cluster.sar\META-INF\jboss-service.xml I also tried the second advice and in the jgroup drow test I open two drawing instances and they are able see each other. will happy to here more suggestions Thanks View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3958318#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...