On Thu, Jan 12, 2017 at 08:32:44PM +0000, Justin Krejci wrote:
What are the pros and cons of one design over another? On list or private off list replies would be great; I'd welcome real world experiences (especially any big gotchas or caveats people learned the hard way) as well as just links to previous discussions, PDFs, slideshows, etc. Heck even a good book suggestion that covers this topic would be appreciated.
One important thing to remember when migrating from full mesh to a RR design is that you are reducing information available to the routers in the ASN. When you had a full mesh, each router could select the best path from all available paths, according to its position in the IGP. In a RR environment, by default, routers only have available to them the best routes from the RR's position in the IGP, which can lead to suboptimal exits being selected. Work is being done to allow RRs to compute metrics from the client's position in the IGP: See https://tools.ietf.org/html/draft-ietf-idr-bgp-optimal-route-reflection-13 for more information -- Brandon Ewing (nicotine@warningg.com)