[c-nsp] ibgp convergence time ?

[Gert Doering]

Hi,

On Tue, Sep 30, 2008 at 07:14:50PM +0200, julien leroiso wrote:
> 
> I have 2 bgp routers (named border1 and border2) with a ebgp session to one
> ISP (yyy.yyy.yyy.yyy) and ibgp session (xxx.xxx.xxx.1 and xxx.xxx.xxx.2).
> 
> My border2 is very very slow to converge. After +-3h I didn't get all my
> border1 routes.

This is perfectly normal and to be expected. 

In the following scenario:

 ISP 1 -- border 1 -- border 2 -- ISP 2

border 1 will only send those routes to border 2 that are "best" via ISP1.

For those routes that border 1 will prefer via border 2 -> ISP 2, it
will not send its own prefixes back to border2.

(You can test this by shutting down the session border2 <-> ISP2.  After
this, you should see all routes from border1 --> border2, and no routes
from border2 --> border1)

gert
-- 
USENET is *not* the non-clickable part of WWW!
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Gert Doering - Munich, Germany                             gert at greenie.muc.de
fax: +49-89-35655025                        gert at net.informatik.tu-muenchen.de
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