> > adding a IFF_VETH just for this seems like an overkill. especially
> > when there are other ways to indicate a virtual device type like
> > rtnetlink kind.
> > Also, its best to keep such checks local to veth, maybe with something
> > along the lines of what Andrew suggests above.
>
> Andrew: Nice to hear that my arguments were good.
With DSA switches we somewhat rely on this behaviour, because there is
an extra header in the frame. I recently added code to automagically
increase the MTU, but that does not always work.
> For the actual use case I can not change to MTU on one of the
> interface.
Please could you explain why.
Andrew
