From owner-freebsd-net Wed Dec 4 7: 4:45 2002 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 CF10337B401 for ; Wed, 4 Dec 2002 07:04:42 -0800 (PST) Received: from moebius2.Space.Net (moebius2.Space.Net [195.30.1.100]) by mx1.FreeBSD.org (Postfix) with SMTP id 8BCA543EC2 for ; Wed, 4 Dec 2002 07:04:41 -0800 (PST) (envelope-from maex@Space.Net) Received: (qmail 88060 invoked by uid 1013); 4 Dec 2002 15:04:39 -0000 Date: Wed, 4 Dec 2002 16:04:39 +0100 From: Markus Stumpf To: freebsd-net@freebsd.org Subject: FreeBSD <-> PIX IP comm problem - no ACK received Message-ID: <20021204160439.A66263@Space.Net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i Organization: SpaceNet AG, Muenchen, Germany X-PGP-Fingerprint: 66 F3 75 79 01 D0 B8 5F 1A C7 77 88 4A B6 70 DF Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org I have searched with google and on freebsd.org but my problem is I don't know what exactly to search for :( The machine is a FreeBSD 4.4-RELEASE #0: Fri Oct 26 23:34:42 CEST 2001 CPU: Pentium III/Pentium III Xeon/Celeron (995.68-MHz 686-class CPU) Origin = "GenuineIntel" Id = 0x686 Stepping = 6 Features=0x383fbff the nic is a fxp0: port 0x2800-0x283f mem 0xf4000000-0xf40fffff,0xf4102000-0xf4102fff irq 5 at device 14.0 on pci0 fxp0: Ethernet address 00:03:47:11:2b:ea Problem: I have an email message that is 3374 Bytes. It should be sent via SMTP to another server that is behind a PIX Firewall. The communiction gets tricky at the end of the message, because instead of CR LF "." CR LF packet N contains data CR LF "." CR and the following packet would only contain LF so far so good, but the problem is a) the PIX does never ACK packet N b) packet N+1 never gets out despite the fact that it could be sent according to the window size. I have also tried sysctl -w net.inet.tcp.newreno=0 without any changes as to the behaviour. While I think this surely is a bug in the PIX state machine / TPCI/IP stack I wonder why the FreeBSD doesn't send out the N+1 packet? The window size would be big enough AFAIK. Here's a tcpdump of such a session. The FreeBSD "hangs" sending 2107:3475 on and on because it gets no ACK und doesn't send the final packet. 14:00:36.904944 vmail.space.net.2924 > 10.0.0.1.smtp: S 424064848:424064848(0) win 16384 (DF) 14:00:36.915759 10.0.0.1.smtp > vmail.space.net.2924: S 1023758129:1023758129(0) ack 424064849 win 64240 (DF) 14:00:36.915790 vmail.space.net.2924 > 10.0.0.1.smtp: . ack 1 win 16416 (DF) 14:00:36.952765 10.0.0.1.smtp > vmail.space.net.2924: P 1:115(114) ack 1 win 64240 (DF) 14:00:36.952895 vmail.space.net.2924 > 10.0.0.1.smtp: P 1:23(22) ack 115 win 16416 (DF) 14:00:36.964287 10.0.0.1.smtp > vmail.space.net.2924: P 115:159(44) ack 23 win 64218 (DF) 14:00:36.964334 vmail.space.net.2924 > 10.0.0.1.smtp: P 23:45(22) ack 159 win 16416 (DF) 14:00:36.981656 10.0.0.1.smtp > vmail.space.net.2924: P 159:209(50) ack 45 win 64196 (DF) 14:00:36.981781 vmail.space.net.2924 > 10.0.0.1.smtp: P 45:82(37) ack 209 win 16416 (DF) 14:00:36.993773 10.0.0.1.smtp > vmail.space.net.2924: P 209:251(42) ack 82 win 64159 (DF) 14:00:36.993825 vmail.space.net.2924 > 10.0.0.1.smtp: P 82:123(41) ack 251 win 16416 (DF) 14:00:37.009846 10.0.0.1.smtp > vmail.space.net.2924: P 251:300(49) ack 123 win 64118 (DF) 14:00:37.009966 vmail.space.net.2924 > 10.0.0.1.smtp: P 123:129(6) ack 300 win 16416 (DF) 14:00:37.023160 10.0.0.1.smtp > vmail.space.net.2924: P 300:362(62) ack 129 win 64112 (DF) 14:00:37.023273 vmail.space.net.2924 > 10.0.0.1.smtp: . 129:1497(1368) ack 362 win 16416 (DF) 14:00:37.023284 vmail.space.net.2924 > 10.0.0.1.smtp: P 1497:2107(610) ack 362 win 16416 (DF) 14:00:37.023338 vmail.space.net.2924 > 10.0.0.1.smtp: . 2107:3475(1368) ack 362 win 16416 (DF) 14:00:37.046653 10.0.0.1.smtp > vmail.space.net.2924: . ack 2107 win 64240 (DF) 14:01:41.038062 vmail.space.net.2924 > 10.0.0.1.smtp: . 2107:3475(1368) ack 362 win 16416 (DF) 14:02:45.031617 vmail.space.net.2924 > 10.0.0.1.smtp: . 2107:3475(1368) ack 362 win 16416 (DF) Any ideas what goes wrong? Is there also a problem in the FreeBSD TCP/IP stack? Is it fixed in a later release or is there a chance to get it working with 4.4 ? Thanks in advance \Maex -- SpaceNet AG | Joseph-Dollinger-Bogen 14 | Fon: +49 (89) 32356-0 Research & Development | D-80807 Muenchen | Fax: +49 (89) 32356-299 "The security, stability and reliability of a computer system is reciprocally proportional to the amount of vacuity between the ears of the admin" To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message