select eth interface by MAC address

[Riccardo Murri <riccardo.murri@uzh.ch>]

Hello!

I have a (hopefully easy) question:

We have a few servers with multiple network cards; we install the
servers with FAI, which in turn uses the Debian live NFS root.

However, names that the kernel assigns to the network cards are not fixed
(i.e., they vary across reboots depending likely on probing order)
so I've written a small patch to `components/9990-select-eth-device.sh`
to select a NIC by MAC address instead of only by name.

Now the questions are:

- how can I best test it? (ideally through FAI)
- and how can I submit the patch upstream, if it works?

The patch itself, and the patched script are available at:
https://gist.github.com/157ef6ece0a6069d8110

Thanks,
Riccardo