> > > I've been investigating a problem recently where we were experiencing
> > > intermittent packet loss and errors on the switch to a particular
> > > server.
> > >
> > > In the end we traced the problem to the fact that the server had been
> > > connected to the switch using a crossover cable.
> > >
> > > In my view this shouldn't have worked at all, but it did, albeit at a
> > > reduced rate and with significant errors.
> > >
> > > Can anyone explain why this would actually work? Was the switch or NIC
> > > compensating in some way for the cable being incorrect?
> >
> > Many, if not most, new GB NIC's and switches supports "Auto MDI/MDX"
> > and will support both stright and twisted cables.
>
> In that case, should he have been getting errors at all because of the
> incorrect cable type?

No. The cable type does not explain the errors. If at least one of
his transceivers supports this mechanism, then both are the correct
cable type.

> Does this interfere with auto-sensing speed and duplex? Mismatches
> there often result in lots of packet loss.

Auto MDI/MDX does not make any difference to the detection of speed and
duplex settings. He still has to get this right.

Could it have been a *bad* crossover cable?

/chris