Subject: Re: loopback routes
To: None <>
From: Darren Reed <>
List: tech-net
Date: 05/06/2000 14:42:02
In some email I received from Andrew Brown, sie wrote:
> >> >>>	I still do not understand your goal... anyway,
> >> >>sorry, i didn't really go into that yet.  i wanted to create a "null"
> >> >>network interface, similar to that which one might find on a cisco.
> >> >>useful for blackhole routing, ipfiltering (yes, really!), etc.
> >> >
> >> >	for example, is this insufficient for your goal?
> >> >	# route add -inet -reject
> >> 
> >> okay, that'll blackhole the packets, but i wanna sniff 'em.
> >
> >If you really want to do this, a null connector*/teriminator for a UTP port,
> >get yourself a cheap networking card and send packets out that interface
> >using ipfilter and hardwired IP#/MAC.  ARP information in place, they'll
> >get sent out the interface to nothing.
> will that ensure that the hardware addresses are intact as received?

No.  Once they go up into the IP layer, your MAC addresses are as good
as lost anyway.  It just stops ARPs that will never be answered from
being generated.