From owner-freebsd-net Thu Dec 14 6:53:55 2000 From owner-freebsd-net@FreeBSD.ORG Thu Dec 14 06:53:52 2000 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from modemcable101.200-201-24.mtl.mc.videotron.ca (modemcable140.61-201-24.mtl.mc.videotron.ca [24.201.61.140]) by hub.freebsd.org (Postfix) with SMTP id 84AF737B400 for ; Thu, 14 Dec 2000 06:53:51 -0800 (PST) Received: (qmail 58316 invoked from network); 14 Dec 2000 14:53:49 -0000 Received: from patrak.local.mindstep.com (HELO PATRAK) (192.168.10.4) by jacuzzi.local.mindstep.com with SMTP; 14 Dec 2000 14:53:49 -0000 From: "Patrick Bihan-Faou" To: Cc: Subject: Re: Strange fragmentation needed message Date: Thu, 14 Dec 2000 09:54:33 -0500 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2911.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Importance: Normal Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Hi, You probably need to use tcpmssd from the ports (net/tcpmssd) or use the recently added tcpmss option of PPP for you ADSL link. Look in the archive of this list for TCP MSS and ADSL, and you will find all the information you need. You can also look at http://renaud.waldura.com/doc/freebsd-pppoe/ which is a good paper on your problem. (could somebody add that in the man page for ppp or the freebsd handbook ?) Patrick. "Udo Erdelhoff" wrote in message news:<20001214114843.A85041@nathan.ruhr.de>... > Hi, > I've been experiencing problems with TCP connections. The symptoms are: > > - I can't upload large (>5 KByte) files with ftp, the client reports > "stalled" at file position 19456; the server receives only the first > 1024 Bytes of the file. Downloads work just fine. > - Sending mail (uucp-over-ip) takes a long time. uucico complains about a > timeout, closes the connection, calls again and restarts after 1024 bytes > (2048 for the third connection, etc). > - cvsup fails with > Establishing multiplexed-mode data connection > Running > Detailer failed: Network read failure: Connection timed out > Will retry at ... > > Aborting and restarting cvsup will eventually result in a successfull run. > > The box runs -current (PRE_SMPNG), the connection to the outside is an > ADSL line (768/128). I'm using ppp with the assorted netgraph modules > and ipfw&natd for NAT. Using ppp -nat instead doesn't help. > > I've had to ignore the problems for some time due to RL. I've tried to > analyse the network traffic and found the following messages with > tcpdump -ni tun0 > > 11:36:33.213801 212.185.239.152 > 212.185.239.152: icmp: 212.185.239.152 unreachable - need to frag (mtu 1480) > > 212.185.239.152 being *my* IP-address. > > I don't understand what's going on. Traffic for my machine shouldn't > be routed into the tunnel (i.e. ppp should add a route to 127.0.0.1 for > $MYADDR). And I don't understand the reason for them, either. > > What's going on? > > /s/Udo > -- > >Every program evolves until it is capable of sending email. > Except Microsoft Exchange > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-net" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message