Hi, this is a follow-up/summary of launchpad bug 1675289 [0]. >From the original spec [1], with the OVS driver we should have groups witt the "hash" selection method, and for parameters source IP/port/protocol However this requires OpenFlow 1.5, so we actually have default selection method and no parameters customization. Selection is done on both source and destination [2], so in our case close to the "theorical" parameters. Additionally we can set "lb_fields" via API, but they are not currenly used in the driver. These also sound quite OVS-specific, not sure how other drivers handle it. Anyway, I outlined the possible change to fix this properly in the bug (if I got everything correctly). Feedback and comments welcome! [0] https://bugs.launchpad.net/networking-sfc/+bug/1675289 [1] https://github.com/openstack/networking-sfc/blob/master/doc/source/ovs_driver_and_agent_workflow.rst#group-table-flows [2] https://github.com/openvswitch/ovs/commit/1d1aae0b2f9a149bf74000d975fbf29d133cd9ca -- Bernard Cafarelli