Containers with Ubuntu 12.04.5 LTS are not getting IPv4’s

[despens (Dragan Espenschied)]

For reference, the previous discussion about legacy containers not getting IPV4 via DHCP — the technique is described for LXD but can be applied to incus just the same and for me works just fine for networking of certain legacy containers. The issue with Ubuntu 12.04 in this thread is independent of this.

Containers do not acquire IPv4 address after being transferred to new host

Hello dear LXC people, I did transfer a bunch of containers from an Ubuntu 18.04 LXD version 3.0.3 (installed from repos) to an Ubuntu 20.04 LXD version 4.0.6 (installed with snap). Three privileged containers now fail to acquire an IPv4 address on the new LXD host. All the containers are set up with the standard profile, so get the “same” eth0 device. Their networking works just fine on the previous LXD host. All non-privileged containers work perfectly on the LXD host. Where do I need to st…