Ville wrote:
>
> On Sat, 26 Feb 2000, Jeremy Weatherford wrote:
>
> > Having the ability to pick your MAC address on a local LAN would cause the
> > same problems as putting your card into promiscuous mode -- you could
> > intercept traffic intended for other machines. I really don't see this as
> > being likely.
>
> I'm not quite familiar with the details, but isn't this very much needed
> functionality to put up working 'backup' servers to take over all of a
> high-priority server's tasks when it goes down? [setting MAC's]
>
> This is one of the reasons people should not use MAC-addresses as a way
> of fool-proof box/card-identification, especially when it comes to copy-
> protecting software or trusting the source.
>
> Most NICs do allow it being altered (I'm not familiar with the one
> mentioned in the earlier posting, though).
>
> AFAIR usually the command is ~
>
> # ifconfig eth0 hw ether 00:00:00:00:00:01
> #
That definately makes it **look** like it was set, but unless the
underlying driver does the work to send the bytes out to the card,
then you are just in a fuzzy state where your system only works
when you are watching it with tcpdump, because it's in promisc
mode then! (Don't ask how long it took me to figure **that**
little wierdness out!!) :)
I would say it's definately very much needed, especially as Linux moves
into the world of High Availibility and embedded applications....
Ben
--
Ben Greear (greearb@xxxxxxxxxxxxxxx) http://scry.wanfear.com/~greear
Author of ScryMUD: scry.wanfear.com 4444 (Released under GPL)
http://scry.wanfear.com
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