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

[Stephan von Krawczynski]

Sorry, you misunderstood my writing. I am talking of several hundred vlans
with - of course - different ids and quite some guests (around 50).
There is no way to simplify this setup besides the trivial way of a bridge
that carries all vlan-tagged interfaces. The trivial thing about it is all
these different vlans come in through one trunk. So if vlan-tagged bridging
worked I would have only one bridge interface with 50 guests connected ...

--
Regards,
Stephan



On Thu, 22 Aug 2013 10:29:59 -0700
Tony Su <address@hidden> wrote:

> If you're configuring the all your "hundreds" of guests to connect to
> the same VLAN, then you should able to simply configure all guests to
> connect to the same working bridge device without further
> configuration.
> 
> You're surely not trying to configure hundreds of individual vlans,
> separate ones for each guest?
> 
> Tony
> 
> On Thu, Aug 22, 2013 at 10:04 AM, Stephan von Krawczynski
> <address@hidden> wrote:
> > Hello Tony,
> >
> > thank you for answering, my comments are inline. Just as an additional hint 
> > to
> > what I've tested so far. Since I found vlan bridging not working I 
> > configured
> > the vlan on the host and put that interface to a bridge and over to a virtio
> > device (non-vlan-tagged) in the guest. As you might expect this works
> > perfectly. Unfortunately it is not useable for me, because if you want 
> > several
> > hundred vlans to several guests you will end up configuring hundreds of
> > bridges and interfaces.
> >
> >
> > On Thu, 22 Aug 2013 09:32:42 -0700
> > Tony Su <address@hidden> wrote:
> >
> >> Have you
> >> - Tested without VLAN tags?
> >
> > Yes, works perfectly.
> >
> >> - Verified IP Forwarding is enabled, I usually see this implemented in
> >> /etc/sysctl.conf and not written directly to the /proc files
> >
> > Yes, forwarding is active.
> >
> >> - 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
> >
> > Yes, I played with these a bit but found out that there is no effect on my
> > problem.
> >
> >> - Verified any personal FW is configured properly.
> >
> > There is none.
> >
> >> 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