From owner-freebsd-stable@FreeBSD.ORG Fri Dec 7 12:26:07 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id E9E5820B for ; Fri, 7 Dec 2012 12:26:07 +0000 (UTC) (envelope-from ronald-freebsd8@klop.yi.org) Received: from smarthost1.greenhost.nl (smarthost1.greenhost.nl [195.190.28.78]) by mx1.freebsd.org (Postfix) with ESMTP id 6B13E8FC08 for ; Fri, 7 Dec 2012 12:26:07 +0000 (UTC) Received: from smtp.greenhost.nl ([213.108.104.138]) by smarthost1.greenhost.nl with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.69) (envelope-from ) id 1Tgx0A-00080v-GW for freebsd-stable@freebsd.org; Fri, 07 Dec 2012 13:25:59 +0100 Received: from [81.21.138.17] (helo=ronaldradial.versatec.local) by smtp.greenhost.nl with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.72) (envelope-from ) id 1Tgx0A-0007RU-Ar for freebsd-stable@freebsd.org; Fri, 07 Dec 2012 13:25:58 +0100 Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes To: freebsd-stable@freebsd.org Subject: Re: Using dhclient on WAN if on a box serving DHCP to LAN if References: Date: Fri, 07 Dec 2012 13:25:59 +0100 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Ronald Klop" Message-ID: In-Reply-To: User-Agent: Opera Mail/12.11 (Win32) X-Virus-Scanned: by clamav at smarthost1.samage.net X-Spam-Level: - X-Spam-Score: -1.9 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=disabled version=3.3.1 X-Scan-Signature: d58e29c6f4e42f76447094ef3ccb23d2 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 07 Dec 2012 12:26:08 -0000 On Fri, 07 Dec 2012 12:38:45 +0100, Tom Evans wrote: > Hi all > > Using 9.0-STABLE #1 r230946 - I found it out as I rebooted to prepare > for 9.1, but I think it should be largely irrelevant of version. > > I have a freebsd router that provides all the things a soho router > should on its LAN iface - DNS, DHCP, NAT (via pf). The WAN iface > connects to a ADSL modem operating in bridge mode. > > My ISP has recently forced a change on to me, in order to get service > I have to connect via DHCP, in order for them to give me my static IP. > Apparently this makes their lives a lot easier. Even knowing the IP, > netmask, broadcast and router is not enough, no service will flow > unless a DHCP request has been registered. > > Relevant rc.conf, ale0 is the WAN, em0 is the LAN > > ifconfig_ale0="DHCP" > ifconfig_em0="inet 192.168.1.1 netmask 255.255.255.0" > gateway_enable="YES" > > dhcpd_enable="YES" > dhcpd_flags="-q" > dhcpd_ifaces="em0" > dhcpd_conf="/usr/local/etc/dhcpd.conf" What is in dhcpd.conf? Ronald. > With this configuration, the default route is over the LAN iface. This > causes the dhclient for ale0 to get a response from the local dhcpd > server, not the ISP dhcpd server. This drove me potty! Can anyone > explain why dhcpd, having been told only to listen for DHCP on em0, > responds to ale0? Could this be related to my pf rules, or is it down > to the default route being incorrect? > > Changing rc.conf to this allows the network to come up correctly: > > ifconfig_ale0="inet xx.xx.110.172 netmask 255.255.255.0 broadcast > xx.xx.110.255 DHCP" > defaultrouter="xx.xx.110.1" > > This relies on me knowing that these are the values that dhclient on > the WAN iface will receive from my ISP's DHCP server. How would I > achieve this setup if this information was dynamic or otherwise > unknowable? My ISP could easily change my gateway IP, the only > guarantee I have is that my allocated IP is static. > > So: > > 1) Why does the LAN dhcpd respond to the WAN dhclient? > 2) Is there a better way of specifying this setup, so that it does not > have hard coded addresses in there? > > Thanks in advance for any pointers. > > Tom > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org"