infinispan-jgroups-xsite.xml

<infinispan>
   <jgroups>
      <stack name="xsite" extends="udp">
         <relay.RELAY2 site="LON" xmlns="urn:org:jgroups"/>
         <remote-sites default-stack="tcp">
            <remote-site name="NYC"/>
         </remote-sites>
      </stack>
   </jgroups>

   <cache-container name="clustered">
      <!-- Use the stack -->
      <transport cluster="cluster" stack="xsite"/>
      ...
   </cache-container>
</infinispan>