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route-map & BGP question

Ryuksapple84

I accepted this circuit yesterday and I configured a bgp peering with the ISP. At the same time, I wanted to check the circuit for any drops for the next 24 hrous so I setup a route-map which would keep the old circuit as the best path for BGP.

I want to know how to remove the prepend path from BGP and make this the best path.

Bassically this is what I configured:

route-map AS-PREPEND permit 20
set as-path prepend 65900 65900 65900
!
Router bgp 65900
Neighbor 10.70.252.49 remote-as 65000
Neighbor 10.70.252.49 route-map AS-PREPEND out
!

Thank you for all your help in advance!

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Comments

networker050184

Remove he route-map from the peer.

powmia

With the route-map, you are influencing inbound traffic... you have done nothing to ensure this is not the preferred outbound path.

networker050184 wrote: »

Remove he route-map from the peer.

That will equal the links, you need to remove it here and apply it to the other circuit if you do not wish to prefer the old circuit (with your addition to influence outbound traffic from above).

shednik

What both of these guys said and if you want it done quickly you'll more than likely need to reset the neighbors.

powmia

shednik wrote: »

What both of these guys said and if you want it done quickly you'll more than likely need to reset the neighbors.

Define quickly?

Danman32

I think Ryuk was looking to keep the traffic on the old circuit until the new circuit proved itself.
Cisco Learning Lab has a lab just on this topic.

As the others said, prepending AS is to influence the peers to use the circuit you want them to use, rather than dictating which circuit you'll use. And that really only works if the two circuits are on different AS. Basically you're artificially telling the peers one path is longer to you than the other. It's about the only attribute you can push onto others.
For influencing your outbound choice:
You can increase the weight on the preferred neighbor if you are using a Cisco router.
You can also set local-preference, which is a non-proprietary attribute.

Do a soft reset on the inbound to speed up the change, otherwise it could be several minutes for you to see the effects.

EdTheLad

Danman32 wrote: »

Do a soft reset on the inbound to speed up the change, otherwise it could be several minutes for you to see the effects.

What will happen after several minutes for him to see the effects? He needs to perform either a hard or soft rest for the policy to take affect!