From owner-freebsd-questions@FreeBSD.ORG Wed Oct 15 11:10:29 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 19B521065693 for ; Wed, 15 Oct 2008 11:10:29 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from QMTA09.westchester.pa.mail.comcast.net (qmta09.westchester.pa.mail.comcast.net [76.96.62.96]) by mx1.freebsd.org (Postfix) with ESMTP id B496F8FC1B for ; Wed, 15 Oct 2008 11:10:28 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from OMTA07.westchester.pa.mail.comcast.net ([76.96.62.59]) by QMTA09.westchester.pa.mail.comcast.net with comcast id Sz1E1a00L1GhbT859zAUke; Wed, 15 Oct 2008 11:10:28 +0000 Received: from koitsu.dyndns.org ([69.181.141.110]) by OMTA07.westchester.pa.mail.comcast.net with comcast id SzAT1a0012P6wsM3TzATeH; Wed, 15 Oct 2008 11:10:28 +0000 X-Authority-Analysis: v=1.0 c=1 a=Hhtsdv2kQ0QA:10 a=7q5sDk5WlpcA:10 a=QycZ5dHgAAAA:8 a=fluuXUJysiPSbN1z5aIA:9 a=6Q1YV9s5uqdnSW9QvG0A:7 a=xfME53_yFIq-tsajFme_NH-cJHcA:4 a=EoioJ0NPDVgA:10 a=LY0hPdMaydYA:10 Received: by icarus.home.lan (Postfix, from userid 1000) id B9EA5C9419; Wed, 15 Oct 2008 04:10:26 -0700 (PDT) Date: Wed, 15 Oct 2008 04:10:26 -0700 From: Jeremy Chadwick To: Da Rock Message-ID: <20081015111026.GA75598@icarus.home.lan> References: <48F43EB1.40304@gmail.com> <20081014101733.GA47158@icarus.home.lan> <1224067248.3458.34.camel@laptop1.herveybayaustralia.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1224067248.3458.34.camel@laptop1.herveybayaustralia.com.au> User-Agent: Mutt/1.5.18 (2008-05-17) Cc: freebsd-questions@freebsd.org Subject: Re: How to get my Dad's Win2k system to access internet through my FreeBSD 6.2 system X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Oct 2008 11:10:29 -0000 On Wed, Oct 15, 2008 at 08:40:48PM +1000, Da Rock wrote: > > On Tue, 2008-10-14 at 06:46 -0400, Michael Powell wrote: > > Jeremy Chadwick wrote: > > > > > On Tue, Oct 14, 2008 at 04:55:11AM -0400, Michael Powell wrote: > > [snip] > > >> Next, you will want to configure your FreeBSD machine as a NAT gateway. > > >> In your /etc/rc.conf you will want something like gateway_enable="YES" > > >> and some form of firewall initialization[1]. The gateway_enable is what > > >> allows the forwarding of packets between your rl0 and your rl1, but the > > >> activation of NAT functionality is usually a function contained within a > > >> firewall. So conceptually, the firewall will be "in between" rl0 and rl1. > > >> > > >> There are three different firewalls you can choose from. Configuring the > > >> firewall is usually where the inexperienced get stuck. This subject > > >> material is beyond the scope of this missive, and you would do well to > > >> start reading in the Handbook. But essentially, when you configure NAT in > > >> the firewall your rl0 (connected to the ISP) will be assigned a "Public" > > >> IP address and the NAT function will translate between "Public" and > > >> "Private". > > > > With respect to "NAT", the caveat here is the assumption that your DSL/Cable > > modem is *not* already performing NAT. The situation you do not want to get > > into is having *two* NATs. The content herein is assuming that the external > > (rl0) interface is getting assigned a "Public" IP from the ISP. > > > > If this is the case wouldn't the OP set router_enable=YES instead of > gateway? No. router_enable causes routed(8) to run, which allows for announcements and withdraws of network routes via RIPv1/v2. This is something completely different than forwarding packets. What the OP wants is to route packets from his private LAN (e.g. 192.168.0.0/16) on to the Internet using NAT. That means he has to have a NAT gateway of some kind that forwards and translates packets. That means he needs gateway_enable="yes", which allows IPv4 forwarding to happen "through" the FreeBSD box. In layman's terms, it allows the FreeBSD box to be used a "Gateway" for other computers which are connected to it directly. -- | Jeremy Chadwick jdc at parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB |