From owner-freebsd-questions Thu Sep 5 3: 7:38 2002 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 37DBC37B400 for ; Thu, 5 Sep 2002 03:07:35 -0700 (PDT) Received: from perimeter.co.za (obelix.perimeter.co.za [209.212.102.154]) by mx1.FreeBSD.org (Postfix) with ESMTP id A384943E72 for ; Thu, 5 Sep 2002 03:07:31 -0700 (PDT) (envelope-from bsd@perimeter.co.za) Received: from PATRICK (gateway.mip.co.za [209.212.102.245]) (AUTH: LOGIN bsd@perimeter.co.za) by perimeter.co.za with esmtp; Thu, 05 Sep 2002 12:07:24 +0200 Message-ID: <002801c254c4$308486b0$b50d030a@PATRICK> From: "Patrick O'Reilly" To: "FreeBSD Question List" References: <011301c25292$2e528ce0$b50d030a@PATRICK> Subject: Re: Network Communications stopped for no apparent reason?!? Date: Thu, 5 Sep 2002 12:08:26 +0200 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG From: "Patrick O'Reilly" > Hi all. > > I have experienced something very strange today. A server running 4.6.2 > just stopped talking to the network. I cannot find any clues as to why! > > The only clues I can find are the following entries from > /var/log/messages: > --- > Sep 2 12:08:25 obelix /kernel: dc0: TX underrun -- increasing TX > threshold > Sep 2 12:08:26 obelix /kernel: dc0: TX underrun -- increasing TX > threshold > Sep 2 12:08:26 obelix /kernel: dc0: TX underrun -- using store and > forward mode > --- This has recurred! Could there be a bug of sorts here? Again, the following is found in /var/log/messages: --- Sep 3 22:53:09 obelix /kernel: dc0: TX underrun -- increasing TX threshold Sep 3 22:53:09 obelix /kernel: dc0: TX underrun -- using store and forward mode --- It seems the problem is that the "store and forward mode" only does the store, and not the forward :) I see the message about "increasing TX threshold" pops up from time to time, with no apparent problem, but whenever it is immediately followed by the "store and forward" message then the NIC hangs. I am on 4.6.2-RELEASE. At the time of the problem there was one user logged on, and one ftp session was downloading a distfile. The box is at an ISP's Colo facility, and bandwidth is restricted to 64k (bandwidth is VERY expensive in South Africa!). It appears that cpu load was very high just before the NIC froze up, based on the last data in my mrtg log, but I am not sure what would have caused that since there was very little happening on the box at the time. Anyone have any clues? Regards, Patrick O'Reilly. ___ _ __ / _ )__ __ (_)_ __ ___ _/ /____ __ / __/ -_) _) / ~ ) -_), ,-/ -_) _) /_/ \__/_//_/_/~/_/\__/ \__/\__/_/ http://www.perimeter.co.za To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message