From owner-freebsd-net@FreeBSD.ORG Sun May 18 01:39:53 2014 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 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id E6E4913A for ; Sun, 18 May 2014 01:39:53 +0000 (UTC) Received: from mail.in-addr.com (noop.in-addr.com [208.58.23.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id B7F442B99 for ; Sun, 18 May 2014 01:39:53 +0000 (UTC) Received: from gjp by mail.in-addr.com with local (Exim 4.80.1 (FreeBSD)) (envelope-from ) id 1WlpcL-000JDP-4F; Sat, 17 May 2014 21:10:21 -0400 Date: Sat, 17 May 2014 21:10:21 -0400 From: Gary Palmer To: "Ronald F. Guilmette" Subject: Re: Gateway? Message-ID: <20140518011020.GB56618@in-addr.com> References: <73288.1400368632@server1.tristatelogic.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <73288.1400368632@server1.tristatelogic.com> X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: gpalmer@freebsd.org X-SA-Exim-Scanned: No (on mail.in-addr.com); SAEximRunCond expanded to false Cc: freebsd-net@freebsd.org X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 18 May 2014 01:39:54 -0000 On Sat, May 17, 2014 at 04:17:12PM -0700, Ronald F. Guilmette wrote: > > Forgive me, please for such a rudimentary sort of question. I've > been doing IP networking for more than 15 years, but I never really > plumbed the depths, and thus I only know the basics. > > Quite simply, I'd like to know if the defaultrouter= IPv4 address > specified in my /etc/rc.conf file should be the same as whatever > I normally see as the first hop in an outgoing traceroute. I ask > because for me these two are apparently not the same. Here's what > I have: > > defaultrouter="69.62.255.254" > > and here is one example of a recent outgoing traceroute: > > % traceroute 74.125.239.148 > traceroute to 74.125.239.148 (74.125.239.148), 64 hops max, 52 byte packets > 1 86.255-62-69.res.dyn.surewest.net (69.62.255.86) 28.884 ms 31.395 ms 30.024 ms > 2 216.0.55.209 (216.0.55.209) 26.486 ms 26.024 ms 25.850 ms > 3 ae1d0.mcr1.roseville-ca.us.xo.net (216.156.1.77) 25.384 ms 27.298 ms 27.060 ms > 4 vb1510.rar3.sanjose-ca.us.xo.net (216.156.0.153) 27.289 ms 34.022 ms 36.213 ms > 5 207.88.14.226.ptr.us.xo.net (207.88.14.226) 26.993 ms 26.567 ms 25.568 ms > 6 216.156.84.30.ptr.us.xo.net (216.156.84.30) 24.800 ms 26.432 ms 25.845 ms > 7 209.85.249.5 (209.85.249.5) 26.033 ms 110.066 ms 28.663 ms > 8 66.249.95.31 (66.249.95.31) 26.985 ms 25.285 ms 28.066 ms > 9 nuq05s02-in-f20.1e100.net (74.125.239.148) 26.895 ms 27.434 ms 27.063 ms They could be using some kind of HSRP or VRRP, and the above behaviour would be normal (at least it was the last time I ran HSRP). You set the route to the failover address, but traceroute sees the response from the actual interface address on whichever gateway handles the packet. e.g. router 1 interface 0 has IP x.x.x.2 and is the HSRP master router 2 interface 0 has IP x.x.x.3 and is the HSRP backup HSRP IP is x.x.x.1 Traceroute out and you normally see the answer from the first hop as x.x.x.2 There are other tricks they could be doing as well which would also give the above behaviour. Regards, Gary