Subject: Network vanishing...
To: None <tech-net@NetBSD.ORG>
From: Dan J Fraser <>
List: tech-net
Date: 06/11/1998 15:31:55
I've installed NetBSD 1.3.2 on a server at work, but have been having a few

The system has two NIC's, both Dec chipset.  One of them is connected to a
cable modem, the other is connected to the internal LAN.

Occationaly, it happens that two people on the cable modem segment end up
using the same IP address.  When this happens, it seems that NetBSD somehow
freaks out, and I can no longer talk though the cable modem until the
machine is rebooted.  ifconfig down/up has no effect.  While the network is
"dead", activity lights on the modem and network card are flashing,
indicating that it is probably NetBSD's fault.

Today, I temporarily unplugged the UTP cable between the cable modem and the
NIC.  When they were re-connected, I had the same problem... no network
connection though the cable modem.

tcpdump still seems to see packets coming though the interface.

Through all of this, the internal LAN connection remained unaffected.

How can I figure out exactly what the problem is?  How can I solve it?

Dan J. Fraser <> -- <URL:>
Finger me for PGP public key.  IRC ( nick: Optic
"You can't be too rich, too thin, or have too much swap space."