--- prelude: > Prior to Newton, the default option for 'ovsdb_interface' was 'vsctl'. In Newton 'ovsdb_interface' defaults to 'native'. This change switches the way of communication with OVSDB from the ovs-vsctl tool to Open vSwitch python api to improve out-of-the-box performance for typical deployments. upgrade: - To keep the old default value use 'ovsdb_interface = vsctl' in '[ovs]' section of openvswitch_agent.ini (common path '/etc/neutron/plugins/ml2/openvswitch_agent.ini') if there is a separate openvswitch agent configuration file; otherwise apply changes mentioned above to ml2_conf.ini (common path '/etc/neutron/plugins/ml2/ml2_conf.ini').