RE: BGP distribute list

I always prefer filtering etc on the neighbors. Keeps things cleaner in my opinion

CCIE # 23962

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of Ivan
Sent: Friday, April 17, 2009 4:26 PM
To: Cisco certification
Subject: BGP distribute list

Hello,

Scenario:

R1 ------------ R2
 | |
 | |
 | |
R4-------------R3

each router is in different AS. If you want to filter one prefix on R2 that
originated in R1's AS with distribute list, is it correct to do it globally
under router bgp:

Ex 1:
  router bgp 200
    distribute-list 1 in

or you must put it on every external neighbor:

Ex 2:
router bgp 200
   neighbor R1 remote-as 1
   neighbor R3 remote-as 3
   neighbor R1 distribute-list 1 in
   neighbor R2 distribute-list 1 in

If the task asks to filter prefix from R1, it means filter from all possible
sources (all external peers). So, in that case is it OK to put like in ex. 1
or do you have to do it neighbor by neighbor like Ex 2 ?
Ex 1 works fine.

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Received on Fri Apr 17 2009 - 16:37:55 ART