From owner-freebsd-net@FreeBSD.ORG  Sun Jun 15 17:55:26 2008
Return-Path: <owner-freebsd-net@FreeBSD.ORG>
Delivered-To: freebsd-net@FreeBSD.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 8F7D7106564A;
	Sun, 15 Jun 2008 17:55:26 +0000 (UTC)
	(envelope-from Hartmut.Brandt@dlr.de)
Received: from smtp-3.dlr.de (smtp-3.dlr.de [195.37.61.187])
	by mx1.freebsd.org (Postfix) with ESMTP id 2B0958FC14;
	Sun, 15 Jun 2008 17:55:25 +0000 (UTC)
	(envelope-from Hartmut.Brandt@dlr.de)
Received: from [129.247.12.30] ([129.247.12.30]) by smtp-3.dlr.de with
	Microsoft SMTPSVC(6.0.3790.1830); Sun, 15 Jun 2008 19:42:08 +0200
Message-ID: <48555468.9090203@dlr.de>
Date: Sun, 15 Jun 2008 19:42:00 +0200
From: Hartmut Brandt <hartmut.brandt@dlr.de>
Organization: German Aerospace Center
User-Agent: Thunderbird 2.0.0.14 (Windows/20080421)
MIME-Version: 1.0
To: Olivier Mueller <om-lists-bsd@omx.ch>
References: <1213546323.29846.24.camel@bigapple.omnis.ch>
In-Reply-To: <1213546323.29846.24.camel@bigapple.omnis.ch>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
X-OriginalArrivalTime: 15 Jun 2008 17:42:08.0227 (UTC)
	FILETIME=[2204FB30:01C8CF0F]
Cc: freebsd-net@FreeBSD.org, freebsd-questions@freebsd.org
Subject: Re: mrtg peak on reboot / snmp-issue?
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net>
List-Post: <mailto:freebsd-net@freebsd.org>
List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 15 Jun 2008 17:55:26 -0000

Olivier Mueller wrote:
> Hello,
> 
> Small but curious thing on my freebsd-based systems: when a
> server is rebooted, it generates a peak (or "spike"?) on the
> network mrtg for all interfaces (here just before 1 am): 
> http://8304.ch/om/stuff/mrtg_localhost_1-day.png

This could happen if either the daemon fails to correctly provide 
ifCounterDiscontinuityTime or mrtg fails to correctly interpret 
sysUpTime and/or ifCounterDiscontinuityTime.

> It happens with both net-snmp and ucd-snmp, with a quite standard 
> mrtg installation (generated by cfgmaker). 
> 
> Do you have the same "issue" on your own servers?  All I can add, is
> that there is not such a high traffic after a reboot, and that it
> doesn't happen on similar linux-based systems.


harti