From owner-freebsd-hackers Sun Mar 2 01:52:10 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id BAA02430 for hackers-outgoing; Sun, 2 Mar 1997 01:52:10 -0800 (PST) Received: from sax.sax.de (sax.sax.de [193.175.26.33]) by freefall.freebsd.org (8.8.5/8.8.5) with SMTP id BAA02425 for ; Sun, 2 Mar 1997 01:52:06 -0800 (PST) Received: (from uucp@localhost) by sax.sax.de (8.6.12/8.6.12-s1) with UUCP id KAA01518 for freebsd-hackers@freebsd.org; Sun, 2 Mar 1997 10:52:04 +0100 Received: (from j@localhost) by uriah.heep.sax.de (8.8.5/8.8.5) id KAA09826; Sun, 2 Mar 1997 10:50:06 +0100 (MET) Message-ID: Date: Sun, 2 Mar 1997 10:50:06 +0100 From: j@uriah.heep.sax.de (J Wunsch) To: freebsd-hackers@freebsd.org Subject: Re: truncated-ip - 101 bytes missing... References: <199703020513.PAA19629@genesis.atrad.adelaide.edu.au> X-Mailer: Mutt 0.55-PL10 Mime-Version: 1.0 X-Phone: +49-351-2012 669 X-PGP-Fingerprint: DC 47 E6 E4 FF A6 E9 8F 93 21 E0 7D F9 12 D6 4E Reply-To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch) In-Reply-To: <199703020513.PAA19629@genesis.atrad.adelaide.edu.au>; from Michael Smith on Mar 2, 1997 15:43:50 +1030 Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk As Michael Smith wrote: > I haven't tried PPP yet; looks like we have a bogon in the SLIP code. > Can you try without the VJ header compression? Hmm. Hmm. What should i say? It works! I've had some troubles to actually get it into not doing VJ header compression (the other end is doing VJ auto, so i had to turn both off there initially). After this, it continues to work. I haven't fetched the entire missing 1.5 MB over my slow modem though. However, there were still some truncation warnings: 09:35:08.737767 141.30.61.11.20 > 193.175.26.65.40011: . 28673:29185(512) ack 1 win 16384 [tos 0x8] 09:35:08.800051 193.175.26.65.40011 > 141.30.61.11.20: . ack 29185 win 16384 (DF) [tos 0x8] 09:35:09.142489 truncated-ip - 101 bytes missing!141.30.61.11.20 > 193.175.26.65.40009: . 4278714882:4278715394(512) ack 1706015121 win 16384 [tos 0x8] 09:35:09.500867 141.30.61.11.20 > 193.175.26.65.40011: . 29185:29697(512) ack 1 win 16384 [tos 0x8] 09:35:09.600096 193.175.26.65.40011 > 141.30.61.11.20: . ack 29697 win 16384 (DF) [tos 0x8] 09:35:09.851295 141.30.61.11.20 > 193.175.26.65.40011: . 29697:30209(512) ack 1 win 16384 [tos 0x8] Is there anybody from the IP gurus who could make some sense out of this? Maybe the problem is in the path MTU discovery, and it's only that SLIP's VJ header compression prevents the connection from recovering? (My PPP attempt did also run with VJ compression, but since it's using an MTU of 1500, this might be a totally different picture.) There are only two routers between me and the FTP server in question, both are some sort of (older) Ciscos. Ah well, no, there's a third router of course, the PPP/SLIP server on the other end, running FreeBSD 2.1. -- cheers, J"org joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE Never trust an operating system you don't have sources for. ;-)