From owner-freebsd-net@FreeBSD.ORG Tue Mar 10 02:49:51 2015 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 9DC3113B for ; Tue, 10 Mar 2015 02:49:51 +0000 (UTC) Received: from mail-pa0-f42.google.com (mail-pa0-f42.google.com [209.85.220.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 71D3BCE0 for ; Tue, 10 Mar 2015 02:49:51 +0000 (UTC) Received: by pabrd3 with SMTP id rd3so53596402pab.5 for ; Mon, 09 Mar 2015 19:49:50 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:message-id:date:from:user-agent:mime-version:to :subject:content-type:content-transfer-encoding; bh=5u6FuHd/VLBKBw3nCBWQbnBGHjrvI0htZflTysaOIbQ=; b=PYQjuFJnoSD0WnyEaevzxWGFOTCO31a8B/rQa0apJMgw0t0Ov3e1WFLVlBbOyMz5x9 TOEAoLSbrgeQUdwj1VIfVNvDRIMvsnm+bBriDkC4aP1IybrN7dywPN6HSqQXTcJS6BPi v2/j7Pxfo46BmEwCh0xNe/nJeS21oqxo0Cm2ZjH3N2GWYlwK4zWopZ2tyAJAGaPZlYl8 wYS+cMirLIYnsbYcCLa+2q7U4p2eUlGFYi1CNlho9xz12VbUTYFRcM8NkyZG96N829Gq ZQV31FhyV0jRFASDojIaMkh7e8KxZCg4IeRhCCxWayBrBs3gFb94Lc3y5LwmjcMdvIP4 q/mQ== X-Gm-Message-State: ALoCoQlbvyUqYIurtwbYkhiNjU41IBC6IBzdY1d4uUUBeuAAK+1v6e5ttH1Zp+wX7uJZQAJ1RvSW X-Received: by 10.66.63.106 with SMTP id f10mr60759001pas.0.1425954416637; Mon, 09 Mar 2015 19:26:56 -0700 (PDT) Received: from [192.168.1.149] ([118.179.177.178]) by mx.google.com with ESMTPSA id y2sm21347331pdm.31.2015.03.09.19.26.54 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 09 Mar 2015 19:26:56 -0700 (PDT) Message-ID: <54FE566F.5030607@winterei.se> Date: Tue, 10 Mar 2015 11:26:55 +0900 From: "Paul S." User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: freebsd-net Subject: FreeBSD responding with wrong receiving interface IP Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 10 Mar 2015 02:49:51 -0000 Hi, I've been deploying FreeBSD as customer edge routers for customers with sites that do not require high throughput (>1g/s). Each site has two ISPs (Mostly Telstra + Verizon/Optus), and take full routes via OpenBGPd and BIRD. I use next-hop self on all received routes. The FreeBSD boxes have static routes delegating the announced IP blocks to a L3 switch down the road. i.e: route add -net 10.100.1.0/24 10.0.0.1, and then that /24 is originated via BGP to both upstreams. Things in general work fine, but I've been receiving reports of 'weird traceroute results' from my customers. Examples of this would be, 1 some.random.isp (...) (...) 2 gigabitethernet3-3.exi1.melbourne.telstra.net (203.50.77.49) 0.309 ms 0.284 ms 0.227 ms 3 bundle-ether3-100.exi-core10.melbourne.telstra.net (203.50.80.1) 1.966 ms 1.675 ms 1.852 ms 4 bundle-ether12.chw-core10.sydney.telstra.net (203.50.11.124) 16.707 ms 15.917 ms 16.360 ms 5 customer-gw.syd.ALTER.net (...) (...) This traceroute seems to claim that the packet was received over the Verizon gateway, which in reality it was not -- it was received directly over the Telstra interface, but my outbound AS-PATH towards some.random.isp uses Verizon. So FreeBSD replies back with the Verizon address. Another person having the same issue (mostly, but on OpenBSD) can be found at http://openbsd.7691.n7.nabble.com/BGP-responding-with-wrong-IP-address-td90264.html I would love to know if there's a way to fix this, or if I've missed something, or if there's something wrong in the way I set it up. Thank you for taking the time to read.