if_bridge on a vlan-trunk

[Andrew Thompson]

On Fri, Oct 12, 2007 at 02:59:44PM -0500, Erik Osterholm wrote:
> On Fri, Oct 12, 2007 at 08:46:53AM +1300, Andrew Thompson wrote:
> > On Thu, Oct 11, 2007 at 09:42:15PM +0200, Jon Otterholm wrote:
> > > Hi.
> > > 
> > > Does anyone know if it is possible to put a transparent bridge on a
> > > vlan-trunk?
> > 
> > As from rev1.100 of if_bridge back in June it will correctly use the
> > vlan number if the forwarding table so it is now possible to bridge a
> > vlan trunk. Is this all you need? (7+ only, it wont be in 6-stable)
> 
> Does anything special need to be done in order for this to work?  I've
> got a machine running a recent snapshot (7.0-CURRENT-200709) where it
> simply isn't bridging the trunk.  It looks like ARP isn't getting
> passed.  If I remove the FreeBSD box from the line, everything works.
> If I explicitly create VLANs interfaces on the FreeBSD box and just
> bridge the VLAN interfaces, it works.
> 

It doesnt need anything special to work. If you go 'ifconfig bridge0
addr' it should show the forwarding table with the correct vlan.

 00:11:bb:48:ca:02 Vlana100 em0 1200 flags=0<>

Can you tcpdump on em0, em1 and bridge0 to see where the arp is being
dropped.


cheers,
Andrew