[nova][neutron] Persistent PCI topology for network interfaces

Hi, we have come came across the issue that some appliances rely on the PCI topology to assign network interfaces and not the mac address. This is the a problem, because the PCI topology changes, when an instance (the libvirt config) is recreated. Is there a way to make the network interface order persistent in the PCI topology and if not can someone give me a hint on the steps that would need to be done in nova? I think this could be an important feature in general. Thanks Jan ------ E-Mail: jan@uponu.com