From owner-freebsd-questions@FreeBSD.ORG Sat Feb 12 07:41:40 2005 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 060C816A4CE for ; Sat, 12 Feb 2005 07:41:40 +0000 (GMT) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9EB7B43D2F for ; Sat, 12 Feb 2005 07:41:39 +0000 (GMT) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.13.1/8.13.1) id j1C7fdR8076230; Sat, 12 Feb 2005 01:41:39 -0600 (CST) (envelope-from dan) Date: Sat, 12 Feb 2005 01:41:39 -0600 From: Dan Nelson To: "Andrew P." Message-ID: <20050212074138.GD49626@dan.emsphone.com> References: <420D7EE3.5000305@mail.ru> <20050212040327.GA49626@dan.emsphone.com> <420D8177.30600@mail.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <420D8177.30600@mail.ru> X-OS: FreeBSD 5.3-STABLE X-message-flag: Outlook Error User-Agent: Mutt/1.5.7i cc: FreeBSD-Questions Subject: Re: Concealing short disconnects 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: Sat, 12 Feb 2005 07:41:40 -0000 In the last episode (Feb 12), Andrew P. said: > Dan Nelson wrote: > >In the last episode (Feb 12), Andrew P. said: > >>I have a few machines behind my FreeBSD box. The box connects to > >>ISP via ppp (PPPoE protocol). It's all working very nicely, but the > >>ISP is a pain - it disconnects every 24 hours. I can reconnect in > >>just a moment - so the diconnect is usually less than a second > >>long, but many applications, like ICQ/MSN and games "feel" the > >>disconnect. The matter is that these applications can handle fairly > >>large packet loss (e.g. Counter-Strike can cope with at least > >>15-second long 100% packet loss), but AFAIK it's in the nature of > >>the TCP/UDP that a disconnect is a disconnect. > >> > >>As I know that FreeBSD is full of magic, is there any way to > >>conceal these reconnects as short moments of 100% packet loss? I am > >>ashamed to know very little about protocols' technicalities, but > >>I'll look into any sources you advise. > > > >Check to see if your IP number changes when you reconnect. If it > >does, there's nothing you really can do; the remote system you were > >talking to knew you only by your old IP, and those packets coming to > >them from this other IP are unrelated. > > It changes only once in about a week. Let's say it doesn't change > at all. What then? I'm still suspicious :) The two most common causes for connection resets are IP address changes and NAT resets. /usr/sbin/ppp keeps its NAT table across disconnects as long as the process itself stays running, so I don't think that's the cause. If you have root access to a remote system, try running tcpdump on it and your local machine while running something like top over ssh, and watch what happens when your connection drops and reconnects. -- Dan Nelson dnelson@allantgroup.com