The traffic will go over whatever interface the HA-JNDI service is configured to use (which is typically an external interface, as HA-JNDI is used by clients). I wouldn't say this was by design; it's more a side effect of using RMI. To make it go away you would need to: 1) Configure HA-JNDI to use the internal interface (set the BindAddress attribute in the HA-JNDI section of cluster-service.xml.) Obviously this is only an option if you don't have external clients that need HA-JNDI. 2) Prevent exchange of internal interface RMI stubs for clustered EJBs: a) Use the PooledInvokerHA instead of the JRMPInvokerHA for clustered EJBs. Simplest is to edit conf/standardjboss.xml looking for occurences of <invoker-mbean>jboss:service=invoker,type=jrmpha</invoker-mbean> and replacing them with <invoker-mbean>jboss:service=invoker,type=pooledha</invoker-mbean> OR b) Configure the JRMPInvokerHA (in cluster-service.xml) to use the internal address (set the "ServerAddress" attribute.) Again, this is only an option if you don't have external clients that need the EJBs. There is a JIRA for 5.0 to convert HA-JNDI to use Remoting, which will remove the RMI issue for that service. For 5.0 clsutered EJBs already use Remoting. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3966990#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...