From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: ICMP echo reply fails Date: Fri, 26 Mar 2010 23:06:30 +0100 Message-ID: <1269641190.2256.1.camel@edumazet-laptop> References: <2acbd3e41003261448q26cb19d4w63487894b24f0254@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org To: Andy Fleming Return-path: Received: from mail-bw0-f209.google.com ([209.85.218.209]:65386 "EHLO mail-bw0-f209.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753656Ab0CZWGg (ORCPT ); Fri, 26 Mar 2010 18:06:36 -0400 Received: by bwz1 with SMTP id 1so2186544bwz.21 for ; Fri, 26 Mar 2010 15:06:34 -0700 (PDT) In-Reply-To: <2acbd3e41003261448q26cb19d4w63487894b24f0254@mail.gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: Le vendredi 26 mars 2010 =C3=A0 16:48 -0500, Andy Fleming a =C3=A9crit = : > For various reasons, we have been running a stress test on one of our > boards. The test consists of initiating 2-3 flood pings from a > Windows box running Cygwin, plus one additional ping we use as a > "heartbeat". The ping flood is overwhelming our board (we're droppin= g > packets at a prodigious rate), but the board continues to respond for > a while. In addition, we are running a script on the board which > alternates bringing up and bringing down the interface every ten > seconds. After a highly variable amount of time, the board stops > replying to the pings. We suspected a driver issue, however, on > closer inspection, we are still able to send and receive packets (I > can ping *from* the board to the PC, and I can *telnet* from the PC t= o > the board). We tried pinging the board from another PC, and it also > failed. Essentially, ICMP echo requests are being ignored (A glance > at memory indicates that packets are arriving, but no packets are > being enqueued to the ethernet controller). We still have a lot more > debugging to do, but I was wondering if anyone had ever seen somethin= g > like this, or might be quicker to realize the obvious mistake we're > making. >=20 > Thanks, > Andy Fleming kernel version ? NIC driver ? Are ICMP echo request received ? (grep Icmp /proc/net/snmp)