openvswitch firewall has been in Neutron tree since Newton and has gone
through lots of improvements since including simple upgrade path from
the iptables hybrid driver.
We have a tempest job running in Neutron tree with openvswitch firewall
that's been voting and stable for a while. For neutron_tempest_plugin,
we have had the openvswitch firewall in use since the beginning.
This patch proposes openvswitch firewall driver to become a default
driver for openvswitch agent deployments.
Change-Id: If26d0180e459210511f25f1faa83dd8ccea25ff4