added a second forwarding rule for port 8181
diff --git a/xos/configurations/cord/README-VTN.md b/xos/configurations/cord/README-VTN.md
index d585d5c..8c25be8 100644
--- a/xos/configurations/cord/README-VTN.md
+++ b/xos/configurations/cord/README-VTN.md
@@ -31,6 +31,7 @@
     # we need NAT rule so the neutron vtn plugin can talk to onos
     # change 172.17.0.2 to the IP address for the ONOS container (use "docker inspect")
     iptables -t nat -A PREROUTING -i br-ex -p tcp --dport 8101 -j DNAT --to-destination 172.17.0.2
+    iptables -t nat -A PREROUTING -i br-ex -p tcp --dport 8181 -j DNAT --to-destination 172.17.0.2
 
 Compute nodes (all of them):