No, it is not. The JGroups channels in nodes meant to be part of different clusters will be listening on the same multicast addresses and ports and will thus see each others traffic. The use of -Djboss.partition.name will prevent that traffic from getting out the JGroups channel, but you still don't want that. See http://wiki.jboss.org/wiki/Wiki.jsp?page=TwoClustersSameNetwork for more on how to isolate clusters. On Windows XP the problem discussed in the "Why isn't it sufficient to change the group name and multicast address? Why do I need to change the multicast port if I change the address?" section of that wiki page doesn't apply. So, simple way to ensure different clusters don't see each others' traffic is to add -u some_multicast_address to the list of params you pass to run.bat. Use a different "some__multicast_address" for each of your 6 clusters. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4137609#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...