From owner-freebsd-net@FreeBSD.ORG Thu Oct 14 01:48:07 2004 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7695E16A4CE for ; Thu, 14 Oct 2004 01:48:07 +0000 (GMT) Received: from outbound0.sv.meer.net (outbound0.sv.meer.net [205.217.152.13]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2420A43D2F for ; Thu, 14 Oct 2004 01:48:05 +0000 (GMT) (envelope-from gnn@neville-neil.com) Received: from mail.meer.net (mail.meer.net [209.157.152.14]) i9E1lHUt085658; Wed, 13 Oct 2004 18:47:18 -0700 (PDT) (envelope-from gnn@neville-neil.com) Received: from minion.local.neville-neil.com (pc1.oakwoodazabu1-unet.ocn.ne.jp [220.110.140.201]) by mail.meer.net (8.12.10/8.12.2/meer) with ESMTP id i9E1l1Lc093378; Wed, 13 Oct 2004 18:47:01 -0700 (PDT) (envelope-from gnn@neville-neil.com) Date: Thu, 14 Oct 2004 10:46:58 +0900 Message-ID: From: gnn@FreeBSD.org To: "Stephane Raimbault" In-Reply-To: References: User-Agent: Wanderlust/2.10.1 (Watching The Wheels) SEMI/1.14.5 (Awara-Onsen) FLIM/1.14.5 (Demachiyanagi) APEL/10.5 Emacs/21.2 (powerpc-apple-darwin) MULE/5.0 (SAKAKI) MIME-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: text/plain; charset=US-ASCII cc: net@FreeBSD.org Subject: Re: Error 49, socket problem? X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 14 Oct 2004 01:48:07 -0000 At Wed, 13 Oct 2004 09:36:03 -0600, Stephane Raimbault wrote: > > I doubt it's a DoS attack, however it could very well be. > Well, probably not, given what you told us below. > In this particular setup, apache runs on port 80 and 81. A slimed down > version of apache handles basic http requests on port 80 and on port 81, we > have a beefier version of apache with php running applications. We proxy > the request from port 80 to port 81 so the client only ever sees connections > to port 80. > > What I find strange is other applications on the server freak out when this > is happening in the same manner. such as php not able to make mysql > connections with a similar error. The errors aren't limited to 127.0.0.1 > either, it seems to be an overall problem with the box, not specifically the > loopback or apache. > > PHP Warning: mysql_connect(): Can't connect to MySQL server on > 'dbm.xxx.xxx.com' (49) in /www/index.php on line 4060 > > In this case the above dbm.xxx.xxx.com resolves to 10.0.12.22 which is one > of the MySQL server's in the cluster. > > I've ruled out that it's a problem with the MySQL server in this case, > because I have 4 other web servers (running apache) able to connect to that > MySQL server during the same time. All web servers in this cluster seem to > exhibit the error randomly at diffrent times. Not only during high peak > traffic times as previously thought. > > Are there buffers I could be running out of? What should I be checking? > Perhaps something in sysctl... If I know what I should probably be looking > at, I can probably monitor and have certain variables logged / graphed for a > better idea of what is going on. > What version of FreeBSD are you running? I would check the interfaces (ifconfig -a), routing table (netstat -rn), and then the rest of the network statistics (man netstat) when this happens. Does it happen reliably or intermittently? Later, George