On Fri, Jan 14, 2000 at 11:57:58AM -0500, Anne Bennett wrote:
> Jonathan Stone addresses my network difficulties:
> 
> > First, if you manually configure full-duplex, you *MUST*
> > manually configure full-duplex on the remote end of the point-to-point
> 
> Well, I didn't touch the switch, so presumably it is already configured
> as full duplex.  (That switch is managed by another group.)

Much better to presume that it is set to autonegotiate. Especially if
it works when you try talking 10Mb to it.

Autonegotiation starts when the link comes up, so if your card powers
up in 10Mb the switch will agree to 10Mb, and when you ask the card
to set 100Mb there's no guarantee the hardware provides a way to take
the link down - and force the switch to autonegotiate again.

Perhaps you have a config disk for your card, and you can set it to
power up in 100Mb?

> I am told that the switch is a "3com Superstack II switch 3300".

I've seen 3coms fail to negotiate properly, leaving a useless link.
Especially for critical machines, disable negotiation, and fix the
config at the speed+duplex you want to use.

> > The trick I found to fix it was to drop link pulse by ifconfig'ing the
> > interface down. That forces the link peer to restart auto-negotiation,
> > which usually ends up in a `good' state.  [...]

(More of a question for Jonathan) Is that de specific? I'm certain that
ifconfig-ing  carious cards 'down' didn't drop the link.

> I tested just now ("ifconfig de0 media autoselect"), and it just ends
> up back in "media: Ethernet autoselect (10baseT)".

Once set, you need to drop the link. Otherwise the switch has already
settled on 10Mb and it will convince the card to.

-- 
David Maxwell, david@vex.net|david@maxwell.net -->
All this stuff in twice the space would only look half as bad!
					      - me