nanog mailing list archives
Re: IBGP Question --- Router Reflector or iBGP Mesh
From: "Alexei Roudnev" <alex () relcom net>
Date: Wed, 12 Jan 2005 00:06:19 -0800
Are you sure? RR should just distribute routes. RR do not make any route decisions, and (btw) iBGP do not make route decisions - they are mostly based on IGP routing. All iBGP + RR are doing is: - tie external routes to internal IP; - distribute this information using iBGP mesh, RR's etc. - receive this information and set up routing using internal IP (which are routed by IGP protocls). End routers receives iBGP routes and uses IGP (OSPF or EIGRP or anything you use) for route decisions (of course, we can image exceptions, but normally , it works so that all decisions are based on IGP routing). Most important decisions are done , where routes are emitted from EBGP into iBGP, others - by iGP; which decisions are done by RR's themself?
On Tue, 2005-01-11 at 13:09, Daniel Roesen wrote:One of the main problems of route reflection is that the best path decision is done centrally. The best route is not seen as from the router making the forwarding decision, but from the route reflector's point of view. Depending on network topology, geographic spread end peering/transit topo, this might/will have significant negative effects.This is where good use of clusters and logical network design are necessary, but I don't think this is a route-reflector specific problem, more a general networking problem once your network starts groing and you start deploying a more complex edge/core based topology. I don't think this is a reason to not use reflection as oppossed to full mesh. Cheers, -- --- Erik Haagsman Network Architect We Dare BV tel: +31(0)10 7507008 fax:+31(0)10 7507005 http://www.we-dare.nl
Current thread:
- IBGP Question --- Router Reflector or iBGP Mesh Erik Sundberg (Jan 07)
- RE: IBGP Question --- Router Reflector or iBGP Mesh Robert Crowe (Jan 07)
- RE: IBGP Question --- Router Reflector or iBGP Mesh Erik Haagsman (Jan 07)
- RE: IBGP Question --- Router Reflector or iBGP Mesh Eric Kagan (Jan 10)
- RE: IBGP Question --- Router Reflector or iBGP Mesh Erik Haagsman (Jan 11)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Philip Smith (Jan 11)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Daniel Roesen (Jan 11)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Erik Haagsman (Jan 11)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Alexei Roudnev (Jan 12)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Iljitsch van Beijnum (Jan 12)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Erik Haagsman (Jan 12)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Alexei Roudnev (Jan 12)
- Re: IBGP Question --- Router Reflector or iBGP Mesh David Barak (Jan 12)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Alexei Roudnev (Jan 13)
- RE: IBGP Question --- Router Reflector or iBGP Mesh Erik Haagsman (Jan 07)
- RE: IBGP Question --- Router Reflector or iBGP Mesh Robert Crowe (Jan 07)
- Re: IBGP Question --- Router Reflector or iBGP Mesh Iljitsch van Beijnum (Jan 11)