nanog mailing list archives
RE: iBGP next hop and multi-access media
From: "Jason Lixfeld" <jlixfeld () andromedas com>
Date: Mon, 7 Oct 2002 08:29:53 -0400
Ok, so correct me if I'm wrong here (I'm just trying to paint a picture of what this thread is trying to conceive), RA-FA1: 10.10.10.1/30, RB-FA0: 10.10.10.2/30, 172.16.16.1/24 secondary? iBGP setup between RA & RB, RB announces to RA with a next-hop of the primary address on FA0, RA announces to RB with a next-hop of the primary address on FA1. When iBGP announces 172.16.16 to RA, you want it announce with a next-hop of 172.16.16.1 as opposed to the primary address 10.10.10.2. Is that right?
-----Original Message----- From: owner-nanog () merit edu [mailto:owner-nanog () merit edu] On Behalf Of Ralph Doncaster Sent: Monday, October 07, 2002 12:56 AM To: Jason Lixfeld Cc: 'Alex Rubenstein'; nanog () merit edu Subject: RE: iBGP next hop and multi-access media It's a theoretical question. So far I've had one person email me saying OSPF can advertise a subnet as local on a shared multi-access media. If in fact BGP can't do this, then it's no big deal to me as nothing in my network relies on this functionality. Ralph Doncaster principal, IStop.com On Mon, 7 Oct 2002, Jason Lixfeld wrote:Are you just asking a question to get a better understanding of how things work, Ralph or have you already put this intoproduction and arewondering why it doesn't work a certain way?-----Original Message----- From: owner-nanog () merit edu [mailto:owner-nanog () merit edu] On Behalf Of Ralph Doncaster Sent: Monday, October 07, 2002 12:43 AM To: Alex Rubenstein Cc: nanog () merit edu Subject: Re: iBGP next hop and multi-access media My understanding is the route is valid as long as the interface is up; just like adding a secondary IP on the interface. Ralph Doncaster principal, IStop.com On Mon, 7 Oct 2002, Alex Rubenstein wrote:Aha. So, if you route to a ethernet interface, it will try toarp for thataddress on that subnet, even without having a local addresson the samesubnet? This seems to me to be something you don't want to do. Is the entire route valid as long as the router can ARP forone of theaddresses in the routed subnet? On Mon, 7 Oct 2002, Ralph Doncaster wrote:On Mon, 7 Oct 2002, Alex Rubenstein wrote:I've been doing ip route statements going on 8 yearsnow, and I can'timagine why ever -- and how it would even work -- you'dwant to ip route anetblock with a next hop of a multi-access brandcastmedia. As in, thenext hop is still truly undetermined. I guess I don't know this because I've never tried it.But, how does therouter determine where to send the packets for a routestatement asspecified above (ip route a.b.c.d e.f.g.h f0/0) ?When you setup a secondary ip on an interface int fa0/0 ip address a.b.c.d e.f.g.h secondary How does it determine where to send the packets? ARP. Which is the same as adding the route described above. -Ralph-- Alex Rubenstein, AR97, K2AHR, alex () nac net, latency,Al Reuben ---- Net Access Corporation, 800-NET-ME-36,
http://www.nac.net --
Current thread:
- Re: iBGP next hop and multi-access media, (continued)
- Re: iBGP next hop and multi-access media E.B. Dreger (Oct 06)
- Re: iBGP next hop and multi-access media Ralph Doncaster (Oct 06)
- Re: iBGP next hop and multi-access media jlewis (Oct 06)
- Re: iBGP next hop and multi-access media Ralph Doncaster (Oct 06)
- Re: iBGP next hop and multi-access media Alex Rubenstein (Oct 06)
- Re: iBGP next hop and multi-access media Ralph Doncaster (Oct 06)
- Re: iBGP next hop and multi-access media Alex Rubenstein (Oct 06)
- Re: iBGP next hop and multi-access media Ralph Doncaster (Oct 06)
- RE: iBGP next hop and multi-access media Jason Lixfeld (Oct 06)
- RE: iBGP next hop and multi-access media Ralph Doncaster (Oct 06)
- RE: iBGP next hop and multi-access media Jason Lixfeld (Oct 07)
- RE: iBGP next hop and multi-access media alex (Oct 07)
- RE: iBGP next hop and multi-access media Ralph Doncaster (Oct 07)
- RE: iBGP next hop and multi-access media alex (Oct 07)
- RE: iBGP next hop and multi-access media Pete Templin (Oct 07)
- Re: iBGP next hop and multi-access media Valdis . Kletnieks (Oct 07)
- Re: iBGP next hop and multi-access media David Schwartz (Oct 07)
- RE: iBGP next hop and multi-access media Stephen J. Wilcox (Oct 07)
- Re: iBGP next hop and multi-access media Christopher L. Morrow (Oct 06)
- Re: iBGP next hop and multi-access media Pete Templin (Oct 07)
- Re: iBGP next hop and multi-access media alex (Oct 07)