From owner-freebsd-questions@FreeBSD.ORG Tue Dec 28 00:30:35 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E8C3816A4CE for ; Tue, 28 Dec 2004 00:30:35 +0000 (GMT) Received: from rwcrmhc11.comcast.net (rwcrmhc11.comcast.net [204.127.198.35]) by mx1.FreeBSD.org (Postfix) with ESMTP id B52F543D2D for ; Tue, 28 Dec 2004 00:30:35 +0000 (GMT) (envelope-from dgl@kirk.dlee.org) Received: from kirk.dlee.org ([68.49.181.149]) by comcast.net (rwcrmhc11) with ESMTP id <2004122800303201300c83t7e>; Tue, 28 Dec 2004 00:30:32 +0000 Received: from kirk.dlee.org (dgl@localhost.dlee.org [127.0.0.1]) by kirk.dlee.org (8.12.11/8.12.11) with ESMTP id iBS0UVRB046114 for ; Mon, 27 Dec 2004 19:30:31 -0500 (EST) (envelope-from dgl@kirk.dlee.org) Received: (from dgl@localhost) by kirk.dlee.org (8.12.11/8.12.11/Submit) id iBS0UUXH046113 for freebsd-questions@freebsd.org; Mon, 27 Dec 2004 19:30:30 -0500 (EST) (envelope-from dgl) Date: Mon, 27 Dec 2004 19:30:30 -0500 From: Doug Lee To: freebsd-questions@freebsd.org Message-ID: <20041228003030.GL900@kirk.dlee.org> Mail-Followup-To: Doug Lee , freebsd-questions@freebsd.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Organization: Bartimaeus Group User-Agent: Mutt/1.5.6i Subject: Tcpdump says I'm getting incomplete packets; how to find the culprit? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Dec 2004 00:30:36 -0000 I use FreeBSD 4.10-STABLE as a nat/firewall box. When connected to DSL, I got fast web surfing but many gaps in incoming audio traffic using some audio software. I switched to cable, and now audio works great, but at least when I pop open pages in Lynx right on the FreeBSD box, I often experience five-second delays--one at "202 OK" and one or more during the loading of the page. Tcpdump reports that I'm receiving incomplete packets, so I assume the five-second delays are timeouts on my box before a request for packet resends. I'm afraid this is a black art of sorts, but in case there's a well-known solution, I'm all ears: Is there a fairly straight-forward way to track down and/or fix this kind of packet truncation issue? I don't know if the packets are getting truncated before they reach me or somehow on my box. More info on my topology: DSL was PPPoE straight into the fbsd box via a crossed Ethernet cable; the cable modem is connected via the same cable and uses DHCP. Fwiw, the NAT is served to Windows boxen from a second NIC in the fbsd box. The drivers for the two NICs are ed for the Internet side and dc for the local side. For PPPoE, I was using mpd. I use ipfw/natd for firewalling and NAT. I can surely provide more details to anyone who needs them. Please Cc me on replies (I hope this is not rude to ask; I'm just afraid of missing answers). Thanks much. -- Doug Lee dgl@dlee.org http://www.dlee.org Bartimaeus Group doug@bartsite.com http://www.bartsite.com "There's no limit to what a man can do or where he can go if he doesn't mind who gets the credit." Ronald Reagan