Re: mcx(4) and bridge(4)

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Fri, Apr 11, 2025 at 07:43:38PM +0200, Hauke Fath wrote:
> On 4/11/25 19:33, Manuel Bouyer wrote:
> > Looks good; next I would run tcpdump -p on mcx0 and then vlan2;
> > and see if the packets for the domU shows up here. If not, then try again
> > without -p
> 
> There are arp requests from the DomU on vlan2, none on mcx0 with or without
> -p.

And no replies to these requests on vlan2 ?
It's strange that nothing shows up on mcx0.

I don't have experience with mcx but with other drivers (wm, ixg, bge, ...)
tcpdump does show vlan traffic (both incoming and outgoing) when run
on the physical interface. If the interface supports hardware vlan tagging
tcpdump can't show the vlan tag, but it still shows the ethernet packets.

> 
> But the latter also does not show arp requests from outside machines on
> vlan2 -- does it matter for tcpdump(8) that packets on the physical
> interface are vlan-tagged?

For the hardware I have experience with, it doesn't.

It looks like something is wrong with the mcx driver.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--