Predictable Network Interface Names

[Martin <keine-eile@online.de>]

Hi ML members,

I have a bunch of machines, all virtual, where I have to swap the NIC type. Three or four  NIC's per host, e1000 to vmxnet3 for those who may care about. With Predictable Network Interface Names enabled, it should be possible, to do this automated. Not being lazy, I've read the available documents like from Freedesktop.org, and others. What I just do not get is, how do I figure out, what name an interface will have before I put them in?
I have a reference system,here it looks like:

[    0.901733] vmxnet3 0000:0b:00.0 eth0: NIC Link is Up 10000 Mbps
[    0.907950] vmxnet3 0000:13:00.0 eth1: NIC Link is Up 10000 Mbps
[    0.917348] vmxnet3 0000:1b:00.0 eth2: NIC Link is Up 10000 Mbps
[    0.951209] vmxnet3 0000:0b:00.0 ens192: renamed from eth0
[    0.966569] vmxnet3 0000:13:00.0 ens224: renamed from eth1
[    1.021765] vmxnet3 0000:1b:00.0 ens256: renamed from eth2

I got this 'ens' part, no problem. But where do the numbers come from? It's about that PCI address numbers, right? But I don't see, how this translates.
Push me someone into the right direction, please!

Martin