LXC Container imported from Proxmox is binding 192.168.0.1 on the docker0 interface

Howdy!

Today I’ve decided to migrate one of my Proxmox’s LXC containers to LXD, because in my experience it looks like that Proxmox doesn’t fit my needs too well (Proxmox is better if you want to host multiple VMs, if you are building a data center, etc… while my needs are just Docker containers with some stateful containers with LXC)

So I’ve decided to migrate one of my Proxmox containers to LXC, and the first thing that I’ve noticed was… network doesn’t work! Weirdly enough, networking worked if I started a ubuntu:18.04 container, so what gives?

Then I noticed that it was using the IP that I was using in Proxmox, so I found where the network config was (/etc/systemd/network) and edited the config to enable DHCP, then it worked!

Weirdly enough, copying the netplan config from the working ubuntu:18.04 container to the imported container… aaaaand it didn’t work, for some reason netplan --debug apply doesn’t apply the Netplan config, like it didn’t exist.

That preramble above was just so if anyone had the same issue while importing a LXC container created via Proxmox. :3

The real issue is that, for some reason that I can’t figure out why, the docker0 interface is being bound to the imported container and bound to 192.168.0.1. The container is created via lxc launch.

+--------+---------+-----------------------------+------------------------------------------------------+-----------+-----------+
|  NAME  |  STATE  |            IPV4             |                         IPV6                         |   TYPE    | SNAPSHOTS |
+--------+---------+-----------------------------+------------------------------------------------------+-----------+-----------+
| jvgm45 | RUNNING | 192.168.0.1 (docker0)       | fd7a:115c:a1e0:ab12:4843:cd96:626c:e61f (tailscale0) | CONTAINER | 0         |
|        |         | 100.108.230.31 (tailscale0) | fd42:7e2d:8889:cfb2:216:3eff:fe5d:d00b (eth0)        |           |           |
|        |         | 10.139.19.27 (eth0)         |                                                      |           |           |
+--------+---------+-----------------------------+------------------------------------------------------+-----------+-----------+
| test   | RUNNING | 10.139.19.172 (eth0)        | fd42:7e2d:8889:cfb2:216:3eff:fe55:9030 (eth0)        | CONTAINER | 0         |
+--------+---------+-----------------------------+------------------------------------------------------+-----------+-----------+

What could cause this? I think it is a configuration within the container, but I can’t for the life of me figure out why this happens.

Please show lxc config show <instance> --expanded for both containers as well as ip a and ip r inside both containers and on the LXD host.

Actually… I think I found why lmao, my friend had installed Docker on his LXC container even tho he doesn’t use it.

I guess that makes sense, since tailscale0 also shows up in lxc list, because Tailscale is running within the LXC containers (and on the host but I guess that’s beside the point).

This made me a bit confused since on Proxmox you could only see the bound interfaces to the container itself, while lxc list shows the interfaces + IPs within the container.

Anyhow, thanks for your help! Even tho at the end of the day it was me being dumb :slight_smile: