From owner-freebsd-stable@FreeBSD.ORG Mon Mar 31 21:14:14 2008 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6AFF71065671 for ; Mon, 31 Mar 2008 21:14:14 +0000 (UTC) (envelope-from bc979@lafn.org) Received: from zoot.lafn.org (zoot.lafn.ORG [206.117.18.6]) by mx1.freebsd.org (Postfix) with ESMTP id 2FEDE8FC13 for ; Mon, 31 Mar 2008 21:14:14 +0000 (UTC) (envelope-from bc979@lafn.org) Received: from [10.0.1.2] (pool-71-109-162-173.lsanca.dsl-w.verizon.net [71.109.162.173]) (authenticated bits=0) by zoot.lafn.org (8.13.6/8.13.4) with ESMTP id m2VLDvRc024892 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO) for ; Mon, 31 Mar 2008 14:14:13 -0700 (PDT) (envelope-from bc979@lafn.org) Message-Id: From: Doug Hardie To: FreeBSD Stable Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v919.2) Date: Mon, 31 Mar 2008 14:13:57 -0700 X-Mailer: Apple Mail (2.919.2) X-Virus-Scanned: ClamAV 0.88.7/6510/Mon Mar 31 13:04:59 2008 on zoot.lafn.org X-Virus-Status: Clean Subject: Access Problems with 7.0 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 31 Mar 2008 21:14:14 -0000 > I recently upgraded 3 of my 5 servers to 7.0. Two of them are on > new hardware and one is on hardware that used to run 6.2. Since > then, 2 of my thousands of users are unable to access the servers > running 7.0. They can access the server running 6.2 just fine. > What happens is the server receives the SYN packet from the client > properly and then responds with the SYN packet. Nothing more is > heard from the client. The server sends a few duplicates of the SYN > and then drops the connection. > > At this point I am not able to verify that the client receives the > SYN. Neither of them has a clue about tcpdump. The packets look > fine on this end (included later). Both are using Windows, > including XP and Vista. I suspect they are receiving it and not > accepting it for some reason. However, I don't really see anything > that would cause that behavior in the packets. I can't reproduce > the problem here. Every computer I can try works just fine. > > Here is one of the packet traces: > > 11:59:00.630414 00:00:0c:38:6f:e1 (oui Cisco) > 00:a0:cc:3e:87:9e > (oui Unknown), ethertype IPv4 (0x0800), length 66: > cpe-76-169-78-119.socal.res.rr.com.59025 > zool.lafn.org.8000: S > 2779920420:2779920420(0) win 8192 2,nop,nop,sackOK> > > 11:59:00.630634 00:a0:cc:3e:87:9e (oui Unknown) > 00:00:0c:38:6f:e1 > (oui Cisco), ethertype IPv4 (0x0800), length 66: zool.lafn.org.8000 > > cpe-76-169-78-119.socal.res.rr.com.59025: S > 2480373222:2480373222(0) ack 2779920421 win 65535 1460,nop,wscale 3,sackOK,eol> > > 11:59:03.613011 00:00:0c:38:6f:e1 (oui Cisco) > 00:a0:cc:3e:87:9e > (oui Unknown), ethertype IPv4 (0x0800), length 66: > cpe-76-169-78-119.socal.res.rr.com.59025 > zool.lafn.org.8000: S > 2779920420:2779920420(0) win 8192 2,nop,nop,sackOK> > > 11:59:03.613194 00:a0:cc:3e:87:9e (oui Unknown) > 00:00:0c:38:6f:e1 > (oui Cisco), ethertype IPv4 (0x0800), length 66: zool.lafn.org.8000 > > cpe-76-169-78-119.socal.res.rr.com.59025: S > 2480373222:2480373222(0) ack 2779920421 win 65535 1460,nop,wscale 3,sackOK,eol> > Checking with the 6.2 server I see there are some differences in the TCP options. 7.0 includes wscale 3 where 6.2 does not. Is there a way to disable that feature using sysctl to see if thats the issue?