Running a privileged LXD container via libvirt not working newer distros. Works with Ubuntu 14.04

I have a Linux LXD container running under libvirt on Ubuntu 14.04.

As Ubuntu 14.04 is out of support, I am trying to move the application to a Raspberry PI running Buster and a system running Ubuntu 20.04.

The application is an emulated computer using the simH. It needs to open the network device with access to change the MAC address and read it in promiscuous mode.

I want to continue to run the application under libvirt so that I can use management tools that are based on libvirt.

On the Raspberry Pi using a buster based os, the application just reports open failure on the ethernet device.

The setup I used for Ubuntu 14.04 is here:

libvirt-lxc has nothing to do with LXC/LXD unfortunately so unless one of its author happens to be paying attention to this forum, you’re unlikely to be getting a response here.

To add to that, libvirt-lxc is a separate implementation of Linux Containers to what you can find on