From owner-freebsd-questions Thu Jan 10 18:25: 3 2002 Delivered-To: freebsd-questions@freebsd.org Received: from freebsd.tekrealm.net (dsl081-247-162.sfo1.dsl.speakeasy.net [64.81.247.162]) by hub.freebsd.org (Postfix) with ESMTP id E31E937B416 for ; Thu, 10 Jan 2002 18:24:54 -0800 (PST) Received: (from root@localhost) by freebsd.tekrealm.net (8.11.6/8.11.4) id g0B2OsB71045; Thu, 10 Jan 2002 18:24:54 -0800 (PST) (envelope-from elitetek@tekrealm.net) Received: (from elitetek@localhost) by freebsd.tekrealm.net (8.11.6/8.11.4av) id g0B2OrO71037; Thu, 10 Jan 2002 18:24:53 -0800 (PST) (envelope-from elitetek@tekrealm.net) X-Authentication-Warning: freebsd.tekrealm.net: elitetek set sender to elitetek@tekrealm.net using -f Date: Thu, 10 Jan 2002 18:24:53 -0800 From: Andrew Stuart To: Dan Langille Cc: fabrizio.fresco@netsiel.it, freebsd-questions@freebsd.org Subject: Re: routing with PPPoE/DSL on a dual homed gateway Message-ID: <20020110182453.A70804@freebsd.tekrealm.net> Reply-To: elitetek@tekrealm.net References: <3C3DF24A.21937.6E5B5ED@localhost> <2953.213.155.199.202.1010714973.webmail@webmail.cww.telecomitalia.it> <3C3DF7C0.26594.6FB0D2C@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <3C3DF7C0.26594.6FB0D2C@localhost>; from dan@langille.org on Thu, Jan 10, 2002 at 08:21:20PM -0500 X-Virus-Scanned: by AMaViS perl-11 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Thu, 10 Jan 2002 at 20:21:20 -0500, Dan Langille wrote: > On 11 Jan 2002 at 3:09, fabrizio.fresco@netsiel.it wrote: > > > > Everythings working. AFAIK. It's all fine. It's just that I don't > > > know > > > > > > why it's working.... > > > > You are using the tun0 interface and via pppo(ver)e(thernet) you talk with > > your isp. You have a default route, via the tun0 interface, what's wrong ? > > What is wrong is that I don't undertand *WHY* it works. > > I understand that tun0 has the public IP address. > > I am quite sure that the DSL modem is connected to this computer via the > NIC vr0. I checked this by setting up a ping to yahoo.com. There are > two NICs in this box. If I unplug xl0, the pings continues. If I unplug > vr0, the pings stop. I therefore conclude that I conclude that tun0 is > routing out via vr0. How does that work if vr0 has no IP address? > -- > Dan Langille > The FreeBSD Diary - http://freebsddiary.org/ - practical examples > I wont claim to be the most knowledgeable person about ppoe, expecially on unix, but Dan, I believe the answer you are looking for is this: pppoe is not a regular ethernet connection, it is a special protocol. freebsd handles this translation thru tun0, as ppoe has to send the username and password, along with other information to your provider to get you connected. as the guy pointed out above, pppoe stands for PPP Over Ethernet. think of it as a dialup connection, without having to listen to the annoying modem tones, and its virtually the same thing. The ppoe driver reconizes your vr0 card as a card that doesnt have an ip bound to it, thus it tries to use it automatically (or any other card without a binding) as your connection to the internet. tun0 is just the passthru. I hope i cleared up some of this for you, although since i havent dug into the pppoe drivers in depth, there is room for improvement on this.. -- Andrew To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message