Scenario:

1. ovs-vsctl set-manager ptcp:6640
2. using postman, connect to the ovsdb node
3. verify node is in config and operational
4. ovs-vsctl del-manager
5. warning below comes out

possibly related to https://bugs.opendaylight.org/show_bug.cgi?id=3141

2015-06-11 08:43:10,255 | WARN | n-invoker-impl-0 | OvsdbNodeRemoveCommand | 159 - org.opendaylight.ovsdb.southbound-impl - 1.2.0.SNAPSHOT | Node{getNodeId=Uri [_value=ovsdb://192.168.120.31:6640], augmentations={interface org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.ovsdb.rev150105.OvsdbNodeAugmentation=OvsdbNodeAugmentation{getConnectionInfo=ConnectionInfo{getLocalIp=IpAddress [_ipv4Address=Ipv4Address [_value=192.168.120.1], _value=[1, 9, 2, ., 1, 6, 8, ., 1, 2, 0, ., 1]], getLocalPort=PortNumber [_value=45909], getRemoteIp=IpAddress [_ipv4Address=Ipv4Address [_value=192.168.120.31], _value=[1, 9, 2, ., 1, 6, 8, ., 1, 2, 0, ., 3, 1]], getRemotePort=PortNumber [_value=6640], augmentations={}}, getOpenvswitchExternalIds=[OpenvswitchExternalIds{getExternalIdKey=system-id, getExternalIdValue=e942140b-446a-406e-b638-e282b6fb3428, augmentations={}}, OpenvswitchExternalIds{getExternalIdKey=opendaylight-iid, getExternalIdValue=/network-topology:network-topology/network-topology:topology[network-topology:topology-id='ovsdb:1']/network-topology:node[network-topology:node-id='ovsdb://192.168.120.31:6640'],
augmentations={}}], getOvsVersion=2.3.1}}} had no OvsdbNodeAugmentation