# Pastebin 2Frvpc4L
ubuntu@rack-1-m1:~$ cat /etc/network/interfaces
auto lo
iface lo inet loopback
    dns-search maas
    dns-nameservers 192.168.10.5

iface eth0 inet manual

auto juju-br0
iface juju-br0 inet static
    gateway 192.168.10.1
    address 192.168.10.51/24
    mtu 1500
    bridge_ports eth0

auto eth1
iface eth1 inet manual
    mtu 1500

auto wlan0
iface wlan0 inet manual
    mtu 1500

source /etc/network/interfaces.d/*.cfg