[rescue] Two network cards on SS2

[G W Adkins]

Subject: [rescue] Two network cards on SS2


>    initialize, but both of the cards have the same MAC address.
>
The MAC address is stored in the machine's NVRAM, it shouldn't be a problem
for your router provided you don't have both interfaces on the same segment.
(Which if it's a router or bridge, you shouldn't have.)

It could be a problem for other machines if you have other multi-homed
machines which will be doing level three switching/routing stradling the
same two segments.  Seeing the same MAC address on two interfaces looks like
a circular route, triggering spanning tree protocols and/or resulting in
misrouted packets.

On the other hand,  if you have one of the cards which supports an on-board
MAC address of it's own, (few and far between), then good old

setenv  local-mac-address  true

at the OBP,  is your friend.  It will tell such cards to use their own MAC
address instead of the machine's.

Anybody know which S-bus cards support this option?
IIRC, 1881's and FSBE's do not.

George