Again, it depends. DFs at the edge as you're talking about are tricky. We worked on some designs a couple years ago. FIB management can become really tricky, with a lot of big peers and/or connections to the DFZ. If you do it wrong you can get tricky hotspotting or bouncing issues with your N/S traffic.
It's doable of course, but in many circumstances I think these make the most sense down in the aggregation layers of a design. On Thu, Dec 26, 2024 at 9:30 PM Mike Hammett <na...@ics-il.net> wrote: > *nods* Yeah, I knew that's how a traditional chassis worked. In a > distributed setup, you have the option for a single "line card", which > obviously doesn't happen in the traditional chassis world. > > > I do see in a DDCv2 document where they briefly mention 2 compute boxes, > so now that makes sense. I had to look up some of the acronyms because the > document didn't define them within itself. > > > > ----- > Mike Hammett > Intelligent Computing Solutions <http://www.ics-il.com/> > <https://www.facebook.com/ICSIL> > <https://plus.google.com/+IntelligentComputingSolutionsDeKalb> > <https://www.linkedin.com/company/intelligent-computing-solutions> > <https://twitter.com/ICSIL> > Midwest Internet Exchange <http://www.midwest-ix.com/> > <https://www.facebook.com/mdwestix> > <https://www.linkedin.com/company/midwest-internet-exchange> > <https://twitter.com/mdwestix> > The Brothers WISP <http://www.thebrotherswisp.com/> > <https://www.facebook.com/thebrotherswisp> > <https://www.youtube.com/channel/UCXSdfxQv7SpoRQYNyLwntZg> > ------------------------------ > *From: *"Randy Bush" <ra...@psg.com> > *To: *"Mike Hammett" <na...@ics-il.net> > *Cc: *"NANOG" <nanog@nanog.org> > *Sent: *Thursday, December 26, 2024 4:51:45 PM > *Subject: *Re: Distributed Router Fabrics > > >> In a distributed fabric, where is the traditional control plane run? > >> Say I've got 100 BGP sessions of upstream,peer, and downstream across > >> ten routers. Is each pizza box grinding this out on its own, or is the > >> work done on the x86 box mentioned in the larger installations? > > > > one way to think of it is that each pizza box (customer facing ports) > > recognizes control plane messages (e.g. port 179) and "punts" them to > > the control plane box, aka routing engine. > > fwiw, that is pretty much what line cards on a big-box fabric do, punt > to the RE. > > randy > >
