From owner-freebsd-net@FreeBSD.ORG Mon May 5 13:38:03 2008 Return-Path: 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 D33931065670 for ; Mon, 5 May 2008 13:38:03 +0000 (UTC) (envelope-from wmoran@collaborativefusion.com) Received: from mx00.pub.collaborativefusion.com (mx00.pub.collaborativefusion.com [206.210.89.199]) by mx1.freebsd.org (Postfix) with ESMTP id 92C2A8FC0C for ; Mon, 5 May 2008 13:38:03 +0000 (UTC) (envelope-from wmoran@collaborativefusion.com) Received: from vanquish.ws.pitbpa0.priv.collaborativefusion.com (vanquish.ws.pitbpa0.priv.collaborativefusion.com [192.168.2.162]) (SSL: TLSv1/SSLv3,256bits,AES256-SHA) by wingspan with esmtp; Mon, 05 May 2008 09:39:46 -0400 id 00056412.481F0E22.0001130E Date: Mon, 5 May 2008 09:38:20 -0400 From: Bill Moran To: Igor Zinovik Message-Id: <20080505093820.ca62fa93.wmoran@collaborativefusion.com> In-Reply-To: <20080505114938.GA34390@zinovik.kpsu.local> References: <20080505114938.GA34390@zinovik.kpsu.local> Organization: Collaborative Fusion X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.9; i386-portbld-freebsd7.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: freebsd-net@freebsd.org Subject: Re: Trying to find source of collisions X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 05 May 2008 13:38:03 -0000 In response to Igor Zinovik : > Hello, net@ readers. > > I'm relatively new to freebsd networking so i'm asking here, because i > did not found information in man netstat. I have a machine that suffers > from collisions. > > Network interface status: > Name Mtu Network Address Ipkts Ierrs Opkts Oerrs Coll > ed0 1500 00:80:48:c6:a1:82 35885806 4 23583716 0 134590 > ... > rl0 1500 00:00:1c:dc:b8:d6 23455543 0 36137069 0 0 > > This is ordinary RELENG_6_1, with ed0 and rl0 acting as gateway. UTP > cat5 is connected to both NICs. > > So i have three questions: > 1. What can cause such big collisions number? Bad UTP cable? Bad NIC? > Misbeheaving switch? Collisions are caused by a nearly saturated network. If you're seeing collisions, you need to either reduce the amount of traffic on that network segment, or increase the capacity of that segment. However, switches shouldn't have collisions. Either your switch isn't really a switch, or something else is wrong. > 2. Ierr -- seems that some input errors. What are these errors and what > can cause them? My first guess would be that you've got a duplex/speed mismatch between NIC and switch. If it's a managed switch, force the speed duplex on both the switch and the FreeBSD machine to ensure they match. If it's not a managed switch, replace it because it's not working correctly and there's nothing you can do about it. > 3. Should i ever bother about this issue? Yes. Something is wrong and it will be hurting your network performance. -- Bill Moran Collaborative Fusion Inc. http://people.collaborativefusion.com/~wmoran/ wmoran@collaborativefusion.com Phone: 412-422-3463x4023