Re: Partial vs Full tables

[Ca By <cb.list6 () gmail com>]

On Thu, Jun 4, 2020 at 8:04 PM James Breeden <James () arenalgroup co> wrote:

> I have been doing a lot of research recently on operating networks with
> partial tables and a default to the rest of the world. Seems like an easy
> enough approach for regional networks where you have maybe only 1 upstream
> transit and some peering.
>
> I come to NANOG to get feedback from others who may be doing this. We have
> 3 upstream transit providers and PNI and public peers in 2 locations. It'd
> obviously be easy to transition to doing partial routes for just the peers,
> etc, but I'm not sure where to draw the line on the transit providers.

Why draw a line?  Just take their directly connected routes + default.  If
you don’t like traffic mix, filter or play with local pref until you are
happy.

I've thought of straight preferencing one over another. I've thought of
> using BGP filtering and community magic to basically allow Transit AS + 1
> additional AS (Transit direct customer) as specific routes, with
> summarization to default for the rest. I'm sure there are other thoughts
> that I haven't had about this as well....
>
> And before I get asked why not just run full tables, I'm looking at
> regional approaches to being able to use smaller, less powerful routers (or
> even layer3 switches) to run some areas of the network where we can benefit
> from summarization and full tables are really overkill.

It is smart approach and used by many.  I would just be sure your ACL /
policing needs are met too.


> *James W. Breeden*
>
> *Managing Partner*
>
>
>
> *[image: logo_transparent_background]*
>
> *Arenal Group:* Arenal Consulting Group | Acilis Telecom | Pines Media
>
> PO Box 1063 | Smithville, TX 78957
>
> Email: james () arenalgroup co | office 512.360.0000 | www.arenalgroup.co