From owner-freebsd-current@FreeBSD.ORG Wed Mar 26 16:37:48 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id CCC8ABE9; Wed, 26 Mar 2014 16:37:48 +0000 (UTC) Received: from h2.funkthat.com (gate2.funkthat.com [208.87.223.18]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "funkthat.com", Issuer "funkthat.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 83027A2D; Wed, 26 Mar 2014 16:37:48 +0000 (UTC) Received: from h2.funkthat.com (localhost [127.0.0.1]) by h2.funkthat.com (8.14.3/8.14.3) with ESMTP id s2QGbkir080581 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 26 Mar 2014 09:37:47 -0700 (PDT) (envelope-from jmg@h2.funkthat.com) Received: (from jmg@localhost) by h2.funkthat.com (8.14.3/8.14.3/Submit) id s2QGbkZD080580; Wed, 26 Mar 2014 09:37:46 -0700 (PDT) (envelope-from jmg) Date: Wed, 26 Mar 2014 09:37:46 -0700 From: John-Mark Gurney To: Gregory Shapiro Subject: Re: sendmail Broken Pipe Error Message-ID: <20140326163746.GJ60889@funkthat.com> Mail-Followup-To: Gregory Shapiro , Willy Offermans , freebsd-current@freebsd.org References: <20140325103934.GH8104@vpn.offrom.nl> <20140325164316.GC32089@funkthat.com> <20140326111748.GJ27307@vpn.offrom.nl> <20140326162034.GI60889@funkthat.com> <20140326162342.GC72635@C02KN7GSDTY3.corp.proofpoint.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140326162342.GC72635@C02KN7GSDTY3.corp.proofpoint.com> User-Agent: Mutt/1.4.2.3i X-Operating-System: FreeBSD 7.2-RELEASE i386 X-PGP-Fingerprint: 54BA 873B 6515 3F10 9E88 9322 9CB1 8F74 6D3F A396 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html X-TipJar: bitcoin:13Qmb6AeTgQecazTWph4XasEsP7nGRbAPE X-to-the-FBI-CIA-and-NSA: HI! HOW YA DOIN? can i haz chizburger? X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.2 (h2.funkthat.com [127.0.0.1]); Wed, 26 Mar 2014 09:37:47 -0700 (PDT) Cc: Willy Offermans , freebsd-current@freebsd.org X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 26 Mar 2014 16:37:48 -0000 Gregory Shapiro wrote this message on Wed, Mar 26, 2014 at 09:23 -0700: > > > 11:57:56.539788 IP MyServer.com.41115 > Smarthost.com.smtp: Flags [S], seq 1001452351, win 65535, options [mss 1448,nop,wscale 6,sackOK,TS val 407239960 ecr 0], length 0 > > > 11:57:56.555262 IP Smarthost.com.smtp > MyServer.com.41115: Flags [S.], seq 1277075046, ack 1001452352, win 8192, options [mss 1452], length 0 > > > > It should look something like: > > 09:18:34.723280 IP jmgmac.funkthat.com.64724 > h2.funkthat.com.ssh: Flags [.], ack 177, win 33280, options [nop,nop,TS val 1854905469 ecr 3482476972], length 0 > > 0x0000: 4510 0034 d7ac 4000 4006 e1af c0a8 0003 E..4..@.@....... > > 0x0010: c0a8 0004 fcd4 0016 7e48 238e d872 43dc ........~H#..rC. > > 0x0020: 8010 8200 7c08 0000 0101 080a 6e8f 9c7d ....|.......n..} > > 0x0030: cf92 61ac ..a. > > > > Notice the hex output... I didn't see any of that in your output... > > The last packet I was talking about is the last one that had length > > 1448 that your server sent... > > Willy mentioned that this only happened on mail with attachments. Could it be an MTU issue? Specifically, see: > > http://www.sendmail.com/sm/open_source/tips/path_mtu/ I don't see how it could be... If it is litterally only mail with attachments and not large emails w/o attachments, then it's definately not that issue.. He could just disable path_mtu on the server: sysctl net.inet.tcp.path_mtu_discovery=0 to test this, but I'd be surprised if it allows email through, since he's already getting 1448 byte packets through and acked before the hang up occurs... -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."