Re: [Qemu-discuss] qemu guests using 802.1q vlans bridged on host

[Tony Su]

Have you
- Tested without VLAN tags?
- Verified IP Forwarding is enabled, I usually see this implemented in
/etc/sysctl.conf and not written directly to the /proc files
- Disabled all the transparent bridge filters, typicallly at
/proc/sys/net/bridge/* again, although you can write directly to these
files I'd recommend you simply add the commands to your sysctl.conf
- Verified any personal FW is configured properly.

Tony

On Thu, Aug 22, 2013 at 7:39 AM, Stephan von Krawczynski
<address@hidden> wrote:
> Hello all,
>
> I'd like to do something very simple - at least that's what I thought ;-)
> I want a guest to have access to a network just as if he was connected to the
> real card, but set up as bridge on the host and virtio network driver. The
> guest should be able to configure and use some or maybe even many 802.1q vlans
> on this network and the traffic should go out tagged.
>
> So I setup the hosts bridge and connected an intel network card and a qemu
> virtio card. Now the problem: No vlan-tagged traffic from the physical
> interface reaches the guest at all, and no vlan-tagged traffic from the guest
> reaches the physical net over the bridge. One major reason for this is the
> vlan offloading by the host interface card (intel). Another seems to be that
> arp requests are somehow not going through the bridge for the vlans.
>
> I hope that someone here has used 802.1q vlans inside guests before and can
> share some tips how to make this work. Because out-of-the-box it does not. All
> system are linux of course and with latest kernels (3.10.9 currently).
> qemu is 1.5.2.
> Thanks for any hints.
>
> --
> Regards,
> Stephan
>
>