Host: Ubuntu 20.04
OVS bridge: br-ex
Openstack security group: allow all ip4.
Single network interface: 192.168.1.100, gateway 192.168.1.1 (home router).
The IP from the physical interface is moved to br-ex, physical nic added as port (that way I can allocate floating IPs from the home router's network 192.168.1.1/24).
Openstack: two networks, private (10.10.0.0/24), public (192.168.1.1/24).
Virual router (10.10.0.1 / 192.168.1.212) provides NAT to private network.
On the openstack host there's a manually added routing table: 10.10.0.0/24 via 192.168.1.212.
Instance: 10.10.0.135, Ubuntu 20.04 cloud image, default cloud config, except that I enabled root password to debug.