A few key points: 1) If you don't tell JGroups what address to bind to, it doesn't bind to all interfaces, it picks one. So, on a multihomed machine, it's always best to tell it which one to use. 2) There are multiple JGroups channels in an AS (in 4.0.3.SP1, there are two). Http session replication uses a different channel from the one configured in cluster-service.xml. It's channel is configured in tc5-cluster-service.xml. 3) If you don't want to manually edit those file to set bind_addr, it can be done globally by starting jboss with the -b switch ./run.sh -b 3.183.158.1 -c all Doing that sets a global override. Why it works on 3.183.158 and not 10.50.1 is likely the result of some OS/network layer configuration on your machine or on the networking hardware between machines. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4102921#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...