From owner-freebsd-questions@FreeBSD.ORG Fri Mar 25 14:46:49 2005 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A73D216A4CE for ; Fri, 25 Mar 2005 14:46:49 +0000 (GMT) Received: from mail.vdsoft.org (poseidon.vdsoft.org [193.85.147.250]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4F8D443D31 for ; Fri, 25 Mar 2005 14:46:49 +0000 (GMT) (envelope-from dvorakv@vdsoft.org) Received: from [10.0.0.132] (unknown [10.0.0.132]) by mail.vdsoft.org (Postfix) with ESMTP id 2297F47E013; Fri, 25 Mar 2005 15:46:45 +0100 (CET) Message-ID: <4244248C.7090704@vdsoft.org> Date: Fri, 25 Mar 2005 15:47:40 +0100 From: Vladimir Dvorak User-Agent: Debian Thunderbird 1.0 (X11/20050116) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Vladimir Dvorak References: <42441D7A.9000106@vdsoft.org> In-Reply-To: <42441D7A.9000106@vdsoft.org> Content-Type: text/plain; charset=ISO-8859-2; format=flowed Content-Transfer-Encoding: 7bit cc: freebsd-questions@freebsd.org Subject: Re: Postfix and Queues X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Mar 2005 14:46:49 -0000 Vladimir Dvorak wrote: > Hi *, > > I have little, but not annoying problem with Postfix and queuing > management. When two or more big (understand >2 MB) emails are in > active queue, Postfix is trying to deliver them simultaneously. But > moth ago began to apear following message in /var/log/mail : > > 5BCED8EFE3* 4534286 Fri Mar 25 14:25:35 user@mydomain.cz > (lost connection with mailserver.domain.com [aa.bb.cc.dd] while > sending message body) > > ^^ this message is in defer queue and wait for its time, when next try > to deliver comes. During this time comes another big email from local > user, which get stucked in defer queue too. The link start to have > very high load of outgoing mail traffic, but all of them are > unsuccesfully delivered. > > Well, is there any chance to reduce queue to one mail in active queue ? > > The system runs postfix-19991231pl08-29 - I know its very old. > > Thank you in advance. > > I found solution. There is (in front of this mailserver) OpenBSD firewall with "scrub in all". Problem appears, when this messages are targeted to Microsoft MX. MS servers badly handle with IP headers and sets "Dont fragment" bit, when this packet is fragmented. :-) Excerpt from man pf.conf: "Some operating systems are known to generate fragmented packets with the dont-fragment bit set. " If you want to avoid this problem, leave "scrub in all" and use "scrub in no-df". If you have another solution, you are welcome! :-) Vladimir Dvorak -- * VDSOFT.ORG dvorakv@vdsoft.org * * (+420) 602 944 941 http://www.vdsoft.org *