getting an old NIC to work

David Fleck david.fleck at
Sun Nov 6 13:19:55 GMT 2005

On Sat, 5 Nov 2005, Steve Bertrand wrote:
> It appears as though everything is in order. The routes are in place,
> IP/SN is all correct etc.
> You are going to have to take a step down now to the lower layers of the
> network stack.
> Perform this command while plugged into the network and let it run a
> while:
> # tcpdump -n -i pcn0
> What this will do is see if the nic can see traffic coming from other
> machines. Throw some pings at it from another box, and even if the other
> box doesn't get a reply, tcpdump will tell you if the nic can at least
> see the incoming traffic. Also, run tcpdump on another box, and repeat
> the process, but ping from the box with the 'bad' nic in it. Perhaps it
> can send traffic, but just not receive. Doing this both ways will
> indicate either way and may give you a clue.

No indication of activity either way - 'tcpdump' on the affected machine 
sees no packets from elsewhere, 'tcpdump' on a working machine sees tons 
of packets, but none from this machine.

> Further that, even farther down, try a different cable and switch port
> (one at a time). I know that may seem silly, but weirder things have
> happened.

Yes, I know... tried swapping cables/hub ports, no change.

> If all of that fails, due to the fact there is a driver loaded for the
> device, and it is taking all of it's parameters ok, I would say slap a
> new nic in the box and see if you can rx/tx traffic via it. If you can,
> I'd say then there is a problem with the nic itself, and you have
> confirmed it logically and completely.

Well, that may take a few days, until I scrounge up an extra NIC... but 
thanks for the assistance.  At least I know I was going about the testing 
the right way.

David Fleck
david.fleck at

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