On Fri, Jun 08, 2012 at 09:26:35AM -0400, Dave Allan wrote:
On Fri, Jun 08, 2012 at 10:04:31AM +0200, Michal Privoznik wrote:
This feature has been requested for a very long time. However, we had to wait for guest agent to obtain reliable results as user might create totally different structure of interfaces than seen from outside (e.g. bonding, virtual interfaces, etc.). That's the main reason why sniffing for domain traffic can return bogus results. Fortunately, qemu guest agent implement requested part for a while so nothing holds us back anymore.
To make matters worse, guest OS can assign whatever name to an interface and changing MAC inside guest isn't propagated to the host which in the end see original one.
Therefore, finding correlation between interface within guest and the host side end is left as exercise for mgmt applications.
This API is called virDomainInterfacesAddresses (okay, maybe too many plurals) and returns a dynamically allocated array of virDomainInterface struct. The great disadvantage once this gets released, it's written in stone and we cannot change or add an item into it. Therefore we might add a padding into it - something like reserved for future use. On the other hand, everything important is already there - what else we will want to add? :)
How about returning an XML document instead of a struct? We've been burned by structs in the past...
The answer isn't entirely clearcut. I think it depends on what we envision the scope of the APIs to be. If we think this is strictly limited to IP address discovery then I think a struct is satisfactory. If we think we'll want to provide more details like type of NIC, MTU size, etc, then we'd want an XML document. Personally I think we should pretty strictly limit the scope of the APIs to just IP address lists, leaving anything else upto general purpose guest agents (eg Matahari like thing). Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|