From owner-freebsd-hackers Thu Mar 6 15:21:59 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id PAA19086 for hackers-outgoing; Thu, 6 Mar 1997 15:21:59 -0800 (PST) Received: from phoenix.its.rpi.edu (dec@phoenix.its.rpi.edu [128.113.161.45]) by freefall.freebsd.org (8.8.5/8.8.5) with ESMTP id PAA19081 for ; Thu, 6 Mar 1997 15:21:55 -0800 (PST) Received: (from dec@localhost) by phoenix.its.rpi.edu (8.8.3/8.8.3) id SAA00540; Thu, 6 Mar 1997 18:22:40 -0500 (EST) Date: Thu, 6 Mar 1997 18:22:40 -0500 (EST) From: "David E. Cross" Message-Id: <199703062322.SAA00540@phoenix.its.rpi.edu> To: danny@panda.hilink.com.au, jkh@time.cdrom.com Subject: Re: Weirdie with SLIP line seen here too... Cc: hackers@FreeBSD.ORG Sender: owner-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk I am one of the "gurus" at RPI on dialup networking, and I have seen interesting behaviour that mimicks it, but only for specific users. Here are the simplist case symptoms: Client machine is connected to a dialup server (Xyplex) on subnet "A", a "ping" from a sun on subnet "B" to the client works, as long as the ping packet size < ~1400. a ping from my FreeBSD machine to the client always works, up to the largest allowed ping packet size. This has ramifications in that this hold true for ANY ip based packet. Another case is: I can retrieve ANY size web document from my machine, or www.mit.edu, but only documents that are very small << 1400 from the local web server www.rpi.edu. The only solution I have seen to this is to set the MTU = 552. The really weird thing is that this affects 1/10 machines, and there is no commonality. -- David Cross ACS Consultant Rensselaer Polytechnic Institute