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Message-ID: <32FE990D.41C67EA6@whistle.com>
Date: Sun, 09 Feb 1997 19:42:05 -0800
From: Julian Elischer <julian@whistle.com>
Organization: Whistle Communications
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To: John Capo <jc@irbs.com>
CC: "Daniel O'Callaghan" <danny@panda.hilink.com.au>,
        Bill Fenner <fenner@parc.xerox.com>, Jim Shankland <jas@flyingfox.com>,
        freebsd-isp@FreeBSD.ORG, bvt@mp.aha.ru, robert@nanguo.chalmers.com.au
Subject: Re: I give up! no ideas left.
References: <97Feb9.125709pst.177476@crevenia.parc.xerox.com> <Pine.BSF.3.91.970210093512.427V-100000@panda.hilink.com.au> <19970209192139.DR04830@irbs.com>
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J
> 
> I have a version of traceroute that does MTU discovery.


so I presume you'll be polishing this and submitting it to the
traceroute authors? :)

> 
> traceroute to nanguo.chalmers.com.au (203.1.96.5), 30 hops max, 8192 byte packets
>  1  MTU=8166 MTU=4352 MTU=2002 MTU=1492 davsys-gw.davsys.com (199.182.75.1)  6 ms  4 ms  4 ms
>  2  198.211.141.1 (198.211.141.1)  345 ms  338 ms  338 ms
>  3  h4-0-mae-west.netcom.net (163.179.232.90)  345 ms  345 ms  345 ms
>  4  cpe1.hay.mci.net (198.32.136.72)  348 ms  343 ms  344 ms
>  5  core3-hssi2-0.SanFrancisco.mci.net (204.70.1.13)  379 ms  380 ms  378 ms
>  6  204.70.2.174 (204.70.2.174)  560 ms  398 ms  444 ms
>  7  204.70.2.174 (204.70.2.174)  431 ms  375 ms  384 ms
>  8  labtam.SanFrancisco.mci.net (204.189.216.150)  618 ms  575 ms  628 ms
>  9  bc1-f10-s2-3.Brisbane.aone.net.au (203.102.128.213)  649 ms  636 ms  661 ms
> 10  max1.Mackay.aone.net.au (203.61.61.129)  913 ms  721 ms  734 ms
> 11  * max1.Mackay.aone.net.au (203.61.61.129)  720 ms !M=296  733 ms !M=296
> 11 MTU=296  eros.chalmers.com.au (203.1.96.4)  758 ms *  756 ms
> 12  nanguo.chalmers.com.au (203.1.96.5)  753 ms  837 ms  763 ms
> 
> Tcpdump shows that max1.Mackay.aone.net.au is responding correctly.
> 
> 19:15:51.031682 max1.Mackay.aone.net.au > irbs.irbs.com: icmp: chalmers.com.au unreachable - nee
> d to frag (mtu 296)
> 
> John Capo