Subject: Re: Network vanishing...
To: None <tech-net@NetBSD.ORG>
From: Wolfgang Rupprecht <>
List: tech-net
Date: 06/11/1998 15:27:54 (Dan J Fraser) writes:
> 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.

Are you saying that you have two computers plugged into your cable
modem, or that you alternate computers connected to the cable modem?

If so, its your cable modem deciding which MAC address to listen to.
It is most likely a single MAC bridge (like the lancity LCP).  You
can't use this type of cable modem with multiple machines.

If you are saying that someone on the wide-area net is pretending that
they are you by arping for your IP, then you need to get the cable
operator involved.  Someone is stealing your packets, and could well
be trying an arp-based man-in-the-middle attack.

Wolfgang Rupprecht  		<>