MAC addresses, hostnames, and DHCP

[Paul Lussier]

klussier at comcast.net writes:

> Yeah, I thought about that. That is the way that I always set it up on
> a corporate LAN. But there is a need to have APs on the same wired
> network here (this is a lab-thing). It doesn't compromise my corporate
> LAN because the wired and wireless networks in the lab aren't
> connected to the corp. lan :-)

In that case it's just a matter of opening up your company's IP to
anyone within a few hundred feet of the AP :)

I still maintain this is an extremely bad idea, both for
troubleshooting and security reasons...

But, if you're insitent upon this, then, as long as you don't have
both wireless and wired NICs active simultaneously, then what Neil showed:

> > host neilmobilewired {
> >   hardware ethernet 00:40:F4:12:54:96;
> >   fixed-address neilmobile.jenandneil.com;
> > }
> > host neilmobile {
> >   hardware ethernet 00:11:95:04:db:45;
> >   fixed-address neilmobile.jenandneil.com;
> > }

Will work just fine.  The problem comes in if you have both NICs
active simultaneously, since you now have 2 MACs on the same network
claiming the same IP.  And, even though they're on the same network,
they will most definitely be going through different network devices,
which means whatever is at the center of this network will get very
easily confused.  And <insert deity of choice> forbid any one of these
systems decides to have routing turned on, or muck with spanning tree!

-- 

Seeya,
Paul