Multicast (was: Re: [fedora-virt] Multicast on qemu-kvm?)

[Daniel P. Berrange]

On Tue, Sep 22, 2009 at 03:03:57PM +0100, Richard W.M. Jones wrote:
> AIUI multicast between guests requires support in the router, which in
> this case would be the host bridge device, eg. virbr0, or possibly
> dnsmasq.
> 
> I have absolutely no idea if the Linux bridge device can do this though.

IIUC, the Linux bridge code treats all multicast traffic as
broadcast. Crude & effective, but not too scalable. I know
there are BZ open somewhere requesting that it do more 
intelligent things only send multicast traffic to the places
its need togo


Daniel
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