Redistribute EIGRP into BGP with dynamic metric

[Difan Zhao]

Hi there,

I have a topology that I have an ISR that connects to two ASRs. The two ASRs connect to a FW. between ISR and ASRs they are EIGRP and between ASRs and the FW it is BGP. I do redistribution on the ASRs between EIGRP and BGP.

The problem right now is that to keep the traffic symetrical so outgoing and incoming traffic take the same path/ASR. So right now the redistribution part is static so FW always prefer the path via ASR01 for return traffic. However when I manipulate the delay to prefer ASR02 for outgoing traffic, how do I make the redistribution to reflect the metric change so BGP wise it will also choose ASR02 for the return traffic?

Thanks!

Difan

[Difan Zhao · Accepted solution]

Never mind... I think if you don't do anything in the route-map, such as "set metric", it will just carry over the EIGRP metric...

[Georg Pauwen]

Hello,

if you redistribute EIGRP into BGP with the 'redistribute eigrp 1 metric' command, the BGP return path will reflect the metric and chose the path with the lowest metric. So on either ASR, all you would require is to configure the metric to influence the return path.

ASR1

router bgp 1

redistribute eigrp 1 metric 100

ASR2

router bgp 1

redistribute eigrp 1 metric 200

In the example above, the firewall would prefer the path through ASR1 for all redistributed routes, based on the lower metric.

Does that make sense, and does that apply to your situation ?

[Difan Zhao]

Sorry no.. I want it to be more dynamic. With the metric config you would still have to manually change when metric on the EIGRP side changes.. I think I have found a solution for this but this thanks for looking into this