Subject: Re: very strange ethernet problem
To: Jeremy Cooper <jeremy@baymoo.org>
From: Tod Daniels <tod@dca.net>
List: port-sun3
Date: 10/30/2000 21:09:14
I'll agree with Jeremy on this (in fact, he finished typing just before I
did... :-)

SQE was originally a way for a transceiver to determine the functional
state of its collision-detection circuitry.  In essence, it occasionally
transmits a "jam" pattern onto the medium.  This would be viewed as
collision by all your ethernet nodes (including the hub).

Turn it off.  This "feature" has been obsolete for years now...

tod

On Mon, 30 Oct 2000, Jeremy Cooper wrote:

> 
> 
> On Mon, 30 Oct 2000, Mark Abene wrote:
> 
> > Hello.  I'm experiencing a very strange problem on my home LAN, which I've
> > traced back to my two NetBSD boxes being the cause.  The two NetBSD boxes
> > in question are a Sun3/80 and a Sun4/110, running 1.4.2 and 1.3.3,
> > respectively.
> >
> > [ Problem: constant collisions on hub ] 
> 
> The problem that you have described sounds like an ethernet heartbeat
> discrepancy.  What kind of transcievers are you using on your Sun
> boxes?  (I assume you are using a transciever because there are very few
> hubs with multiple DB-15 AUI connectors these days).
> 
> If your transceiver has its heartbeat feature turned on, it will very
> likely cause constant collisions with the hub.  Look around for a switch
> on the transcriever to disable it.  The switch may be labeled 'SQE'
> instead of 'heartbeat'.
> 
> -J
> 
>