Comment 33 for bug 1452601

And suddenly, it has started working.

I don't know why.

I did a reboot
sudo systemctl status lxc-net

The above command suddenly had results which looked familiar, in a good way.

Before this, I had unsuccessfully tried a few of the sample lxc.

Perhaps I updated something which fixed the problems.

Thanks for your help.

I wish I knew exactly what I did.