From owner-freebsd-isp Fri Nov 13 03:07:31 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id DAA21519 for freebsd-isp-outgoing; Fri, 13 Nov 1998 03:07:31 -0800 (PST) (envelope-from owner-freebsd-isp@FreeBSD.ORG) Received: from liquid.tpb.net (drum-n-bass.party-animals.com [194.134.94.34]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id DAA21514 for ; Fri, 13 Nov 1998 03:07:29 -0800 (PST) (envelope-from niels@bakker.net) Received: from localhost (niels@localhost) by liquid.tpb.net (8.9.1a/8.8.8/Debian/GNU) with SMTP id MAA30355 for ; Fri, 13 Nov 1998 12:07:04 +0100 Date: Fri, 13 Nov 1998 12:07:03 +0100 (CET) From: N To: freebsd-isp@FreeBSD.ORG Subject: Re: two routers back to back: Do they need real ip-adresses? In-Reply-To: <19981113090526.A10967@skriver.dk> Message-ID: <981113120350.30188B-100000@liquid.tpb.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-isp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org >> 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? > You can't use unnumbered on broadcast media aka ethernet, so you need to > assign addresses to the interfaces, but these can be RFC1918 addresses, > that is if your ISP is willing to accept this. You shouldn't use private addresses either, this will break Path MTU Discovery if any filters exist between a client and your network. Ripping four addresses from your /24 shouldn't pose much of a problem. Turn off proxy-arp on the Ethernet interface where that /24 is attached to and you have the added benefit of people not being able to access those IP addresses directly. -- Niels. -- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isp" in the body of the message