Forward dot1q frames over unmanaged l2tpv3 tunnel

Hi all,

First time poster - please let me know if this belongs somewhere else. I feel like there is a simple solution to my problem that I'm missing but I'm not too skilled in the area of low-level linux networking.

I'm trying to forward frames that have a dot1q tag over an unmanaged l2tpv3 tunnel.

I've created a bridge br0 and added the logical subinterface eth1.99 and the tunnel interface l2tpeth0 to it.

What I can see when I run a pcap on the physical interface the frames are arriving and are tagged correctly. When I run a pcap on eth1.99, the frames arrive, but they are not tagged. So when the frames are forwarded into the tunnel, they arrive out the other end and the receiving device drops them as they will essentially see them as untagged frames.

I'm wondering what kind of interface I need to configure in order to preserve the tag through the tunnel, so the receiving device handles them as needed.

I can create a diagram if needed and provide any extra info.

Cheers

mr. s