Consistent device naming

[CLOSE Dave]

I manage a lab with more than a hundred machines, all doing the same 
things. Presently they are running Fedora 13 and are obviously sorely 
overdue for an upgrade. But doing an upgrade is likely to present 
several issues, one of which I'd like to discuss today.

The machines come from several manufactures and were purchased over a 
span of years. Their hardware differs substantially but all have two 
Ethernet interfaces. With F13, these are /always/ called eth0 and eth1. 
When one is implemented by an add-in card and the other is on the 
motherboard, the motherboard interface is /always/ eth0.

My experience with newer Fedora releases, on other machines, is that 
this naming reliability has gone away. The names assigned, by default, 
depend on the hardware configuration of the machine. Some may call the 
motherboard port em1, others may call it p1p4, and even more names are 
possible. The add-in port has similarly inconsistent names.

Note, I don't mean the names are inconsistent on the same machine. I 
understand the purpose of the systemd/udev naming rules and how they 
work, but they get in my way.

So I know that I can try to return to the old naming system using one or 
more techniques 
(<http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/>). 
And I've tried them all. But I find that, sometimes the motherboard port 
gets called eth0 and the add-in port is eth1, and sometimes those names 
get reversed. This is /not/ the old behavior even though it uses the old 
names.

I want to run the same software on all of these machines and having 
inconsistent names /between/ the machines makes that next to impossible. 
Using the new names means that my software has to learn all those 
different names and can't easily determine which name applies to the 
motherboard port. Using the old names means it can't predict which name 
will be given to which port.

There's got to be a better answer.
-- 
Dave Close