Master CCNA

How to Master CCNA Ebook

 

 

My book will help you Master CCNA

Master CCNP SWITCH

How to master CCNP SWITCH ebook

 

 

My book will help you Master CCNP SWITCH

Master CCNP ROUTE

How to master CCNP ROUTE Ebook

 

 

My book will help you Master CCNP ROUTE

Print

BGP Communities Delete and Additive

Written by Rene Molenaar on . Posted in BGP

Scenario:

Mushroom Kingdom is stronger than ever before. Some of the citizens have switched their career to become network engineers specializing themselves in BGP. One of the moustached network engineers is sending some communities values along with prefixes but you want to change this slightly.

Goal:

  • All IP addresses have been preconfigured for you.
  • Configure EBGP between AS 1 and AS 2.
  • Configure EBGP between AS 2 and AS 3.
  • Advertise the loopback0 interface on router Mario in BGP.
  • Configure router Mario so it sends community value 100:100, 200:200 and 300:300 along with the update.
  • Configure router Luigi to remove community value 200:200 and add 400:400 instead.

IOS:

c3640-jk9s-mz.124-16.bin

Topology:

BGP Communities Delete and Additive

Video Solution:

You need to a flashplayer enabled browser to view this YouTube video

You need to register to download the GNS3 Topology File. (Registration is Free!)

Related Articles
Only registered users can write comments!

Comments (4)

  • avatar
    ersanka

    Hi Rene,

    I have a problem with the last step. Cause i dont know how to check if i have configured it correctly. I did change for Mario and confirmed it on Toad. So is this config correct for Luigi:


    ip community-list 1 permit 200:200
    !
    !
    route-map CHANGE_COMMUNITY permit 10
    match community 1
    set comm-list 1 delete
    set community 100:100 300:300 400:400

    And where should i add this route-map, back to Toed? or an extra router for testing :P

    Thanks.

  • avatar
    tomaifauchai

    Hi Ersan,

    Here's the config i did on Luigi. If you do the additive on the set statement, it'll preserve the current attributes.

    access-list 1 permit 1.1.1.0 0.0.0.255

    route-map change-community permit 10
    match ip address 1
    set comm-list 1 delete
    set community 400:400 additive

    router bgp 3
    no synchronization
    bgp log-neighbor-changes
    neighbor 192.168.23.2 remote-as 2
    neighbor 192.168.23.2 route-map change-community in
    no auto-summary
    ip bgp-community new-format

  • avatar
    ersanka

    Hi Tom,

    Now i got the point, which is to see the community 400:400 on Luigi. My config was also fine but i just needed to add the route-map on the inbound direction. Then it make sense :)

    Many thanks for response.

  • avatar
    ReneMolenaar

    Sorry for the late response, good to see you guys figured it out 8)