From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751164AbWDZXe4 (ORCPT ); Wed, 26 Apr 2006 19:34:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751220AbWDZXe4 (ORCPT ); Wed, 26 Apr 2006 19:34:56 -0400 Received: from 8.ctyme.com ([69.50.231.8]:48873 "EHLO darwin.ctyme.com") by vger.kernel.org with ESMTP id S1751164AbWDZXe4 (ORCPT ); Wed, 26 Apr 2006 19:34:56 -0400 Message-ID: <4450039F.20704@perkel.com> Date: Wed, 26 Apr 2006 16:34:55 -0700 From: Marc Perkel User-Agent: Thunderbird 1.5.0.2 (Windows/20060308) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: A Question for the Worlds Smartest Network Minds Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I hope this question isn't too far off topic but I'm having a very weird network problem and don't know where to ask it. Perhaps someone could point me in the right direction. I have an unusual packet loss problem that has me stumped. Working at home with a cable modem connected to a Linksys WRT54G router. Behind the router are two computers. One is a Linux server and a windows XP notebook. The Linux box is accessable to the outside world because I opened 3 ports in the NAT. Port 22,25,and 53. The server acts as a name server for the domains I host and it also is a backup spam filtering server receiving many incomming connections on port 25 and sending out far less good email also on port 25 to various other server who I am the front ens spam filter for. Linux box is running FC5 with the latest stock FC5 kernel. Some flavor of 2.6.16. Here's the problem. I can ping the router gateway 192.168.2.1 fine from both computers with no packet loss if I turn off the Exim SMTP daemon. But if I turn it on then I get about 10% packet loss pinging the gateway on both the Linux and Windows computers, both plugged into the Linksys router. Thinking it might be the quantity of traffic I tried uploading a large file with rsync ovser SSH which creates a lot more traffic than the SMTP traffic (which is about 50k or so) and no packet loss. I only get packet loss if I have Port 25 traffic. So - what could cause traffing on just port 25 to cause 2 computers to have backet loss? Could it be related to the number of connections? It does seem like when I turn on the SMTP that it takes a little while before the packet loss starts. Say 3 minutes or so. Thanks in advance.