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 From:  Fred Wright <fw at well dot com>
 To:  m0n0wall at lists dot m0n0 dot ch
 Subject:  Re: [m0n0wall] No carrier between router and computer
 Date:  Thu, 7 Oct 2004 14:24:06 -0700 (PDT)
On Wed, 6 Oct 2004, Chris Buechler wrote:
> On Wed, 6 Oct 2004 21:37:11 +0200, Patrik <paake at telia dot com> wrote:
> > > Sounds like you aren't using an appropriate crossover cable.  Does
> > > laptop <-> m0n0 directly (no hub or switch between) work with the same
> > > cable server <-> m0n0 doesn't work?
> > 
> > All tests have been made with the same and only crossover cable I have.
> > So to answer, yes, laptop <-> m0n0 works with the same cable that
> > server <-> m0n0 doesn't.
> 
> And laptop <-> m0n0 on the same OPT interface does work, correct?  

But no mention of whether laptop <-> server works with the same cable.  
If "cable server" is like "cable modem", it's probably wired MDI-X rather
than MDI-II, so you need a straight-through cable rather than a crossover
cable to connect a computer to it.

Even if laptop <-> server works, that may not prove anything if the
laptop's port has auto MDI/MDIX switching.  The main thing is that if a
known "good" cable doesn't give link status indications on known good
ports, then it's almost certainly the wrong kind of cable.

> Autonegotiation issue possibly?  Possible, though I don't know how
> likely that is.  Can't think of anything else off the top of my head

I'd say extremely unlikely.  Even in the bizarre cases you've described
previously, (which you weren't even sure was autonegotiation or parallel
detection), the only ill effect was duplex mismatch, which doesn't cause a
complete loss of connectivity.

> at the moment that would be system-to-system specific like that.   
> You can try setting speed and duplex on either or both sides.  Not
> going to hurt anything.

Sure it can, if he forgets to remove the useless but not harmless tweaks
when he installs the right kind of cable. :-)

					Fred Wright