[j-nsp] redistribute iBGP learned routes

[Wayne Tucker]

On Sun, Apr 22, 2012 at 9:56 AM, Matthias Brumm <matthias at brumm.net> wrote:
> customer --- eBGP --- access router --- iBGP --- core router --- iBGP
> --- edge router --- eBGP --- transit
>
> How would you establish this? I do not want an iBGP connection from
> access to edge. The only way I see at the moment, is to configure
> edge-routers as route-reflector-client, but that seems to be a rather
> unclean setup.

Your choices for IBGP are 1.) full mesh or 2.) set up route reflection
(in the core or another device depending on what you've got to work
with).

Is there any particular reason you don't want IBGP between access and edge?


> Should I redistriute the customers prefixes in OSPF
> between access and core and advertise them from core to edge via iBGP?

I wouldn't - especially if the customer isn't using a private ASN.


> Maybe there is a policy-statement to achieve this?

I'm not aware of any way to make a non-reflector router advertise
prefixes to an IBGP peer that it learned from another IBGP peer.  Even
if I did, I would neither use it nor recommend its use.

> What would be the best practice here?

small scale: full mesh
medium scale (no firm definition - just a matter of when maintaining
(n**2-n)/2 sessions gets to be troublesome for your environment):
route reflectors
large scale: lots of ways.. may involve route reflectors,
confederations, MPLS and BGP-free core, etc.

:w