On Nov 27, 2007 5:49 AM, Paul Rae <paul at impacttrainingsolutions dot co dot uk> wrote:
> What I find more interesting is that you have collisions on both your LAN
> and DMZ interfaces on the wrap board.
>

That tells me the switches are probably configured the same, or are
flaky in the same way with the WRAP.

I would be willing to bet this is a duplex mismatch, everything lutzn
mentioned points exactly to that. If you force half duplex, the
problem most likely goes away.

Check the configuration of the switches, if they're managed. They
should be on auto speed and duplex, as should m0n0wall. With both
sides on auto, assuming no switch bugs (make sure they have the latest
firmware), this won't be an issue. If they're unmanaged switches, set
m0n0wall to 100 Mb half duplex (*not* full) and it should work around
the issue of failing negotiation. If you insist upon forcing speed and
duplex on your switch (you shouldn't), make sure m0n0wall is
configured the same as the switch.

For more info on why:
http://en.wikipedia.org/wiki/Autonegotiation
http://www.sun.com/blueprints/0704/817-7526.pdf

-Chris