From owner-freebsd-questions@FreeBSD.ORG Thu Feb 10 07:57:19 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 BD66716A4CE for ; Thu, 10 Feb 2005 07:57:19 +0000 (GMT) Received: from toybox.fyremoon.net (toybox.fyremoon.net [209.61.186.20]) by mx1.FreeBSD.org (Postfix) with ESMTP id 432A743D31 for ; Thu, 10 Feb 2005 07:57:19 +0000 (GMT) (envelope-from jadz@toybox.fyremoon.net) Received: from localhost (jadz@localhost) by toybox.fyremoon.net (8.11.6/8.11.7) with ESMTP id j1A7vG728252; Thu, 10 Feb 2005 07:57:17 GMT Date: Thu, 10 Feb 2005 07:57:15 +0000 (GMT) From: jadz@toybox.fyremoon.net To: tinc@tinc-vpn.org, Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Subject: IP packets with source address of 0.0.0.0 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: Thu, 10 Feb 2005 07:57:19 -0000 Hi, I've got a bit of a weird one I've not figured out yet, so thought I'd come see if you guys can help. I've just added a new box to an existing tinc vpn. The vpn consists of some debian Linux and freebsd 5.2 and 5.3 boxes. All boxes are running tinc 1.0.2. The box I've just added is the first and only fbsd 5.3 box on the vpn. tinc on the fbsd5.3 box seems to happily connect to the vpn, but connections to the other systems on the vpn cannot be initiated from it. The reason seems to be that the packets coming from the box over the vpn have a source address of 0.0.0.0. Thats clearly why no packets get returned by the other vpn sites. The if_tap device on the fbsd 5.3 box seems to be configured fine: tap0: flags=8843 mtu 1500 inet6 fe80::2bd:fff:fe33:100%tap0 prefixlen 64 scopeid 0x4 inet 10.0.5.1 netmask 0xffffff00 broadcast 10.0.5.255 ether 00:bd:0f:33:01:00 Opened by PID 3174 I've had a quick look at the routing table and everything is fine there. Using tcpdump on one of the other vpn sites confirms the packets are getting to it, so they are being routed over the vpn correctly: # tcpdump -i tap0 tcpdump: listening on tap0 08:44:24.847529 0.0.0.0 > 10.0.3.1: icmp: echo request 08:44:25.803251 0.0.0.0 > 10.0.3.1: icmp: echo request 08:44:26.818328 0.0.0.0 > 10.0.3.1: icmp: echo request 08:44:27.822987 0.0.0.0 > 10.0.3.1: icmp: echo request 08:44:28.841233 0.0.0.0 > 10.0.3.1: icmp: echo request 5 packets received by filter 0 packets dropped by kernel # In the above example you can see ping packets arriving over the vpn from the fbsd 5.3 box. the destination address is good, but the source address is 0.0.0.0, which is the problem I've done some googling to no joy, so I'm hoping someone out there has some ideas. hope you guys can help jadzy