Certain broken network switches (cabletron's come to mind running securefast)
ignore the spec that a machine connected to different logical networks
can use 1 MAC.

The cabletron's use the MAC as the key for switching traffic and ignores the
vlan information for the ports. So what ends up happening is it rounds robins
packets (and you see horrible packet loss) and packets on either network
appear on the other.

That's one application I've had to change MAC's before since I couldn't get
the switches changed out and Cabletron was convinced that a host returning
1 MAC for all cards was wrong. (Who cares about standards....)
All the new cards allow you to do is have a nvram env variable that specifies
the card to use it's own mac rather than the station mac. By default they
still use the station.

James


>On Fri, 27 Oct 2000, Manuel Bouyer wrote:
>
># For the on-board and some add-on card, you can change the MAC addr in the
># NVRAM. See the sun hardware faq for instructions (there is probably a link
># from the NetBSD docs pages).
>
>Older suns have one MAC address per host, while newer ones may have
>broken it out into one MAC address per interface or card.  I'm relatively
>certain he's trying to get two interfaces on the same host to give
>different MAC addresses, which SunOS/Solamis can do, but we cannot,
>currently.
>
>The idea, I'm sure, was that the machine was not intended to be talking
>with both interfaces on the same logical network.
>
>
># Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
>
>				--*greywolf;
>--
>If anyone requests a reason as to why Windows NT is inferior to UNIX,
>refer them to the process scheduler, for starters.  Of course, users
>don't care, and programmers try not to, even though they both should.
>If that fails, reiterate that remote administration and control of a
>node is a *good* thing, especially if network security is concerned.
>
>
>
>
>