Path: utzoo!utgpu!watserv1!watmath!att!pacbell.com!ucsd!usc!julius.cs.uiuc.edu!zweig
From: zweig@cs.uiuc.edu (Johnny Zweig)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: TCPIP ping problem
Message-ID: <1990Dec14.154507.4590@julius.cs.uiuc.edu>
Date: 14 Dec 90 15:45:07 GMT
References: <9012121414.AA13496@fiamass.ie>
Sender: news@julius.cs.uiuc.edu (USENet News)
Reply-To: zweig@cs.uiuc.edu
Organization: U of Illinois, Dept. of Computer Science, Systems Research Group
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At a wild guess I would say it's an ARP problem.  If neither machine is
answering ARP requests, but both see the requests from the other host and
update their ARP caches you cou ld have a stat in which each machine had to
attempt to ping (or telnet/rlogin/ftp/anything else) the other for them to be
able to talk.  A way to test this would be to have A and B both ping C (which
needn't actually exist) and see if they notice each other.

-Johnny Guessing