[libvirt] vnet<X>'s & interfaceStats().. KVM device numbering confusion?

r-c at rocketmail.com r-c at rocketmail.com
Sat Sep 12 11:19:32 UTC 2009


> > Under my new KVM config I've realised that
> vnet<X> is brought up in a 'first free' fashion as
> opposed to a counter in the Xen case. This leaves me
> scratching my head a little bit, say I have a domain which
> has ended up with ID = 8, but may for instance have network
> 'vnet1' associated with it. I'm not sure how I can determine
> any association between the domain & which interface
> belongs to it! (e.g. a call to domain.interfaceStats()
> requires the correct network interface as a parameter).
> > 
> > Surely I must be missing something here? Anyone have
> any advice/workaround for this situation? Ideally I would
> like to either be able to hardcode vnet-labels in the XML
> description (tried but it's ignored), or otherwise keep vnet
> numbering in sync with domain ID.
> 
>   Ask libvirt for the XML config while the domain is
> running, you should
> see the interface there I think, try "virsh dumpxml 8" 

Hi Daniel, thanks for your fast reply. Yes you're right I can do that and parse the XML (possibly not so elegant but I've tested it and it works! :-)

But I have another question for you.. I would now like to apply iptables rules similar to Xen antispoofing (i.e. lock an IP to a vnet<X> interface). Can you recommend the best place to integrate this functionality? Are there some script hooks? I.e. if I try to add <interface>..<ip />..<script path='/some/script'/> </interface> to my domain definition would it pass the IP address & interface to the script (as what seems to happen with the Xen driver?) or am I approaching this the wrong way again?

Thanks in advance,

Ravi




      




More information about the libvir-list mailing list