Re: [Qemu-devel] net packet storms with multiple NICs

Mark McLoughlin
2009-10-23T16:45:36Z

On Fri, 2009-10-23 at 20:25 +0400, Michael Tokarev wrote:
> I've two questions:
>
> o what's the intended usage of all-vlan-equal case, when kvm (or qemu)
> reflects packets from one interface to another? It's what bridge
> in linux is for, I think.

I don't think it's necessarily an intended use-case for the vlan feature

> o why different -net guest -net host pairs are not getting different
> vlan= indexes by default, to stop the above-mentioned packet
> storms right away? I think it's a wise default to assign different
> pairs to different vlans, by counting -net host and -net guest
> sequences.

With 0.12, we're going to be de-emphasising the vlan feature and instead
have NICs directly connected to host backends. The vlan feature will be
just another host backend, but optional

You'll start guests with e.g.:

-netdev tap,id=tap.0 -device virtio-net-pci,netdev=tap.0

Cheers,
Mark.