...
Where to find reference on exact commands?
Differences between articles,
https://www.theurbanpenguin.com/ubuntu-server-creating-a-bridge-interface/ - mentions for KVM too,
auto br0 iface br0 inet static address 192.168.0.201 netmask 255.255.255.0 gateway 192.168.0.1 dns-nameservers 8.8.8.8 8.8.4.4 bridge_ports eth0 bridge_stp off
https://www.cyberciti.biz/faq/how-to-create-bridge-interface-ubuntu-linux/ - shows bridging with multiple cards... more complicated,
# br1 setup with static wan IPv4 with ISP router as gateway auto br1 iface br1 inet static address 208.43.222.51 network 255.255.255.248 netmask 255.255.255.0 broadcast 208.43.222.55 gateway 208.43.222.49 bridge_ports eth1 bridge_stp off bridge_fd 0 bridge_maxwait 0
auto br0 iface br0 inet static address 10.18.44.26 netmask 255.255.255.192 broadcast 10.18.44.63 dns-nameservers 10.0.80.11 10.0.80.12 # set static route for LAN post-up route add -net 10.0.0.0 netmask 255.0.0.0 gw 10.18.44.1 post-up route add -net 161.26.0.0 netmask 255.255.0.0 gw 10.18.44.1 bridge_ports eth0 bridge_stp off bridge_fd 0 bridge_maxwait 0