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From: michael butler <imb@scgt.oz.au>
Message-Id: <199610100838.SAA19800@asstdc.scgt.oz.au>
Subject: Re: Annoying artifact of the routing code
In-Reply-To: <325C8717.167EB0E7@whistle.com> from Julian Elischer at "Oct 9, 96 10:18:15 pm"
To: julian@whistle.com (Julian Elischer)
Date: Thu, 10 Oct 1996 18:37:58 +1000 (EST)
Cc: hackers@freebsd.org
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Julian Elischer writes:

> The following bug has been annoying us here for ages
> I recently decided to track it down..
 
> set up device (ethernet) to use address A.B.C.D
 
> do some work
 
> change device to new address A.B.C.E
 
I remember having a conversation with Ravi from Cisco in June about this
because I managed to totally confuse one of their routers (required reload)
by doing this :-) 

He seemed to think that the 'correct' thing to do was to invalidate any
cached arp entries (held by others) for the old address by means of some
broadcast on the ether concerned. Is such an arp packet defined or is it a
'Cisco special' ?  If it is a 'standard' mechanism, why don't we use it in
such cases ?

	michael