Thanks.
So in these cases (and you’ll find several on these forums), the issue is almost always one of the following:
- Some other process listening on the DHCP or DNS ports preventing LXD’s dnsmasq from starting.
- Another firewall on the system preventing DHCP packets from LXD containers from reaching the DHCP server.
In your case you are using an unmanaged bridge, and so LXD won’t be running a DHCP/DNS server for your br0 bridge. This rules out 1.
So it is most likely another application on your host that is creating firewall rules blocking DHCP packets from being sent out of br0 to your network’s DHCP server.
I also note that in your host’s interface output you have a docker0 bridge, suggesting you have docker running. This is a big red light to me, as unfortunately Docker is known to modify the host’s firewall in such a way as to often cause DHCP issues.
See Lxd and Docker Firewall Redux - How to deal with FORWARD policy set to drop
I’m not certain at this stage that is the issue, but is certainly the first path to investigate.
Please can you show the output of on the host:
sudo iptables-savesudo nft list ruleset