I tried copying the same network settings as the original device and renaming eth0 to eth1 but when I boot the container there is no second network.
Furthermore even when I comment out the first one, leaving only the second, with the only difference being that the name is eth1 rather than eth0 there is no ip assigned when booted up.
What is going on? It doesn’t seem to like changing the name from anything but eth0
Here are the config settings which work for eth0 but fail as soon as the setting is changed to eth1.
That has nothing to do with LXC. I suspect your eth0 device has an entry in /etc/network/interfaces whereas eth1 hasn’t so dhcp is not ran against eth1. You need to do so manually or put it in /etc/network/interfaces.
If you want multiple network devices simply do: