From owner-freebsd-questions@FreeBSD.ORG Tue Nov 22 22:03:01 2011 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 95201106564A for ; Tue, 22 Nov 2011 22:03:01 +0000 (UTC) (envelope-from j65nko@gmail.com) Received: from mail-qw0-f54.google.com (mail-qw0-f54.google.com [209.85.216.54]) by mx1.freebsd.org (Postfix) with ESMTP id 58EAE8FC26 for ; Tue, 22 Nov 2011 22:03:01 +0000 (UTC) Received: by qadc10 with SMTP id c10so706643qad.13 for ; Tue, 22 Nov 2011 14:03:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=O6ElV2fH9Tl3YVA6GQ/A04jvkMtgUj9wSzftiobAbKE=; b=BKpC9Zhe/sVwKx3vS96qVPDh4bcoydJVU2Kc+863UzoLjYdD5DnCIXSoCiR9UCRhX7 YADizUDvkXexicrbObTdJM80GFfqFFKbOlVJvYD0Uzg+pAIBagotnCtzomB9S12ygnk+ 2N/0r8jzYS7+tEaNHchTQkILoUc8J9oLaAtPM= MIME-Version: 1.0 Received: by 10.224.194.137 with SMTP id dy9mr10006265qab.65.1321999380664; Tue, 22 Nov 2011 14:03:00 -0800 (PST) Received: by 10.229.82.66 with HTTP; Tue, 22 Nov 2011 14:03:00 -0800 (PST) In-Reply-To: References: Date: Tue, 22 Nov 2011 23:03:00 +0100 Message-ID: From: J65nko To: Kees Jan Koster Content-Type: text/plain; charset=ISO-8859-1 Cc: freebsd-questions@freebsd.org Subject: Re: Diagnosing packet loss X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Nov 2011 22:03:01 -0000 On Tue, Nov 22, 2011 at 9:33 PM, Kees Jan Koster wrote: > Dear All, > > I am stuck with a machine that shows serious packet loss (about 1% of all traffic is dropped). I tried the obvious (new network cable, different switch port, different ethernet interface on the machine), but the problems remain. > > Another machine that sits in the same rack and is hooked up to the same switch shows no such packet loss issues. The problematic machine is a dual Opteron with FreeBSD 8.2-STABLE from Thu Aug 11 14:05:47 CEST 2011. > > The machine is lightly loaded. A MySQL slave is running, but the machine is not serving queries. Plus a Munin server process. > > I am at a loss where to start diagnosing this. Can you advise me where to look? Are there network buffers that may be overflowing? > -- To check input/output errors and collisions : netstat -in Detailed TCP/IP statistics: netstat -s or netstat -ss Checking Receive and Send Queue : netstat -an -f inet Buffers: netstat -m Adriaan