diff --git a/opencontrail/control/cluster.yml b/opencontrail/control/cluster.yml
index 7e30779..a4126d6 100644
--- a/opencontrail/control/cluster.yml
+++ b/opencontrail/control/cluster.yml
@@ -13,6 +13,9 @@
           version: 0.9.0-0contrail0
         python-kafka:
           version: 1.0.1-0contrail1
+      kernel:
+        modules:
+        - nf_conntrack_ipv4
   opencontrail:
     web:
       database: