[pve-devel] Port BR_GROUPFWD_RESTRICTED patch for Layer 1-esque Linux Bridge forwarding

[Dietmar Maurer]

Using an extra bridge device for each point-to-point connection is
very clumsy. I thought about introducing a new type of virtual
network connection (and maybe call it vcable) to directly connect
two network devices using an UDP tunnel. Config would look like:

net0: vcable=200net1 # connect to VM200 device net1

Qemu already provide a UDP socket tunnel, and I guess it should be possible
to use that for this purpose. AFAIR cumulus VX documentation has some example
to use this. The current qemu tunnel implementation requires to manually assign
UDP ports - this is clumsy and we should try avoid that.

Above would work on a local host only, but it should also be possible to
implement
a user space daemon which tunnels the traffic to other nodes if required....

> On August 24, 2018 at 9:00 AM Jesus Llorente <jesus.llorente at gmail.com> wrote:
> 
> 
> Hello,
> 
> I am working on a scenario that uses virtual machines to run a switch
> appliance. The aim of my test is not performance, but to test different
> configurations and network models. However, I have stumbled upon something
> that depends on the kernel which is making Linux bridges consume link local
> multicast packets (LLDP, LACP, etc) in compliance with 802.3ad