Hi, Following the conversation [1]: My understanding was that the way to use out of the tree vif_driver is to set vif_driver option in nova.conf until there is a better way to support such cases but the commit [2] removed this option. Can someone clarify the current status (i.e. what is the current way to do it ) in Juno? [1] https://www.mail-archive.com/openstack-dev@lists.openstack.org/msg30177.html [2] https://github.com/openstack/nova/commit/7561c8ded211d53e8745d1420a73b82bd0fc35cf <https://github.com/openstack/nova/commit/7561c8ded211d53e8745d1420a73b82bd0fc35cf-> (libvirt: remove vif_driver config parameter) Thanks, Itzik