"Austad, Jay" wrote: > > Can one of you network gurus explain how this is legal, by > > Ethernet specs? > > I'm a little out of date, but MAC addresses were supposed to > > be sacrosanct physical IDs that are unique for each card. Of > > course this was late 70's or early 80's, and there was no > > danger of running out of them! > > Yes, that's true, they are supposed to be unique for every card, but some > manufacturers have produced so many cards that they have had to repeat > addresses. However, it is sometimes useful to be able to change them. For > example, if you have a redundant firewall setup using the HA stuff for linux > and one firewall fails and you have to switch over to the other one, you > have to change the MAC addresses also to prevent any interruption in network > service, at least when using cisco routers. They could also be reusing the MAC addresses from there original cards... The ones that no one in there right mind should be using anymore? That's the only use I've found for a couple OLD ISA cards sitting around (Ya.. I know ISA is still usable. Not these... Trust me). Plug em into an old system. Get the MAC address. Trash the card. Solves your problem. :-) Interesting idea for a recycling business..... sim