From owner-freebsd-net Wed Jun 24 05:56:39 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id FAA27106 for freebsd-net-outgoing; Wed, 24 Jun 1998 05:56:39 -0700 (PDT) (envelope-from owner-freebsd-net@FreeBSD.ORG) Received: from ktpk.dp.ua (ktpk.dp.ua [195.24.130.245]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id FAA26869 for ; Wed, 24 Jun 1998 05:55:43 -0700 (PDT) (envelope-from os@ktpk.dp.ua) Received: from admin.dnepr.com (admin.dnepr.com [192.168.0.4]) by ktpk.dp.ua (8.8.7/8.8.7) with SMTP id PAA06460 for ; Wed, 24 Jun 1998 15:54:06 +0300 (EEST) (envelope-from os@ktpk.dp.ua) From: "Oleg Semyonov" To: Subject: FreeBSD+natd = tcp connection problems Date: Wed, 24 Jun 1998 15:59:17 +0400 Message-ID: <01bd9f67$83b3f9e0$0400a8c0@admin.dnepr.com> MIME-Version: 1.0 Content-Type: text/plain; charset="koi8-r" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 4.71.1712.3 X-MimeOLE: Produced By Microsoft MimeOLE V4.71.1712.3 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Hi all! I have some problems with tcp connections to some servers (ftp, irc and some others). My network configuration is quite simple: FreeBSD box is connected via slip (sl0) to IP provider (BSDI 2.1) and via NIC (de0) - to LAN (Win95/NT workstations). I have one real IP for FreeBSD box and private network 192.168.0.* for LAN. Natd is used for NAT, and all was ok, but... PROBLEM DESCRIPTION: When I trying to ftp to some servers from FreeBSD, in some cases I can enter login/password, and then see only first 230- line, and connection hangs. When using password in form of -user@ (disable that 230- messages) - all ok. For example, connect to ftp.kiae.su and ftp.hp.com was failed, connect to ftp.microsoft.com - ok. Then I found that we are using different MTU values on both sides of slip link (308 by defaul on BSDI, 507 by default on FreeBSD). I'm setting my side to 308. All ok, ftp with no problems. But only from FreeBSD box. Workstations from LAN via natd cannot ftp with same problem: 230- and stop. Workstations on LAN and de0 interface on FreeBSD are using MTU=1500. Next stage was to replace slip by ppp with mtu=1500. Effect was same: dropped connections from FreeBSD (and LAN too). Changing ppp0 MTU to 296-308 solves problem, but for FreeBSD box only. LAN cannot ftp to such servers. Irc connections from LAN hangs in same manner. What is the reason and what can I do? Does anybody help me? PS. Sorry for not so good English... --- Oleg Semyonov, the Head of IT Department of KTPK "Dnepr", Energodar, UA Internet mail: os@altavista.net, finger/talk: os@ktpk.dp.ua, ICQ:12900788 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message