The ovs-ofctl tool is used to monitor and administer OpenFlow switches. The Neutron Open vSwitch agent uses ovs-ofctl to program flows on the virtual switches that are used to dictate traffic flow, perform VLAN tagging, perform NAT, and more.

Useful commands include the following:

• ovs-ofctl show <bridge>: Shows OpenFlow features, actions, and port descriptions for the specified bridge.
• ovs-ofctl dump-flows <bridge> <flow>: Prints the flow entries for the specified bridge. If the flow is specified, only that flow is shown.
• ovs-ofctl dump-ports-desc <bridge>: Prints port statistics for the specified bridge, including the state, peer, and speed of the interface.