diff --git a/lib/neutron_plugins/ml2 b/lib/neutron_plugins/ml2
index 00bd716..6ac20fe 100644
--- a/lib/neutron_plugins/ml2
+++ b/lib/neutron_plugins/ml2
@@ -20,7 +20,7 @@
 source $TOP_DIR/lib/neutron_plugins/${Q_AGENT}_agent
 
 # List of MechanismDrivers to load
-Q_ML2_PLUGIN_MECHANISM_DRIVERS=${Q_ML2_PLUGIN_MECHANISM_DRIVERS:-}
+Q_ML2_PLUGIN_MECHANISM_DRIVERS=${Q_ML2_PLUGIN_MECHANISM_DRIVERS:-openvswitch,linuxbridge}
 # List of Type Drivers to load
 Q_ML2_PLUGIN_TYPE_DRIVERS=${Q_ML2_PLUGIN_TYPE_DRIVERS:-local,flat,vlan,gre,vxlan}
 # Default GRE TypeDriver options