From owner-freebsd-isp Thu Nov 12 20:00:22 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id UAA15677 for freebsd-isp-outgoing; Thu, 12 Nov 1998 20:00:22 -0800 (PST) (envelope-from owner-freebsd-isp@FreeBSD.ORG) Received: from magicnet.magicnet.net (magicnet.magicnet.net [204.96.116.9]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id UAA15667 for ; Thu, 12 Nov 1998 20:00:20 -0800 (PST) (envelope-from bill@bilver.magicnet.net) Received: (from root@localhost) by magicnet.magicnet.net (8.8.6/8.8.8) with UUCP id WAA05613 for freebsd-isp@freebsd.org; Thu, 12 Nov 1998 22:55:01 -0500 (EST) Received: (from bill@localhost) by bilver.magicnet.net (8.9.1/8.9.1) id XAA21999 for freebsd-isp@freebsd.org; Thu, 12 Nov 1998 23:03:44 -0500 (EST) From: Bill Vermillion Message-Id: <199811130403.XAA21999@bilver.magicnet.net> Subject: Re: two routers back to back: Do they need real ip-adresses? In-Reply-To: from Leif Neland at "Nov 13, 98 01:29:52 am" To: freebsd-isp@FreeBSD.ORG Date: Thu, 12 Nov 1998 23:03:44 -0500 (EST) X-Mailer: ELM [version 2.4ME+ PL38 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-isp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Leif Neland recently said: > We had to put in a cisco 1605 router (with 2 ethernet ports) between our > net and our isp supplying our backbone connection. > The "ethernet", which is only a crossed 10BT cable between the two > routers, does it need real ip adresses? > > > +-----------+ +-----------+ +----+ ----- > --our net---+ E0 E1 +------+ E0 S0 |-----+ | \ > 3C's | 1605 | | 100x | | +---- > +-----------+ ^ +-----------+ +----+ > | > Can I use 192.168.1.0-adresses here? > Or even unnumbered ip? As long as both routers know about the other and it is an ethernet connection - just hook them together. I did that in the process of moving 4 C's from one provider to another. It made it convenient and then I could upgrade the IOS on the first. > Our uplink isp wants us to subnet one of our C's in a /30, is this > really nessecary? That's typically the address of the serial port. A /30 gives a four address range. The network number, 2 IPS, and a broadcast number. The ones I've seen have the ISP as the lower of the two addresses and the client as the upper of the two. These normally are not part of your address space. The only time I did that in our address space was when I remoted another router over a T1 - and had to pull the addresses to use from our name-space. There might be other ways to do this - as I'm still a newbie at networking. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isp" in the body of the message