BGP Cluster IDs

[4everlearning]

Hi Guys,

Can you explain what is the different of having the multiple RRs using the same Cluster ID vs. using different cluster IDs?

What is the benefits of both designs? which design is preferred and why?

Thanks,

[Jose Jara]

Hi,

If you use different RR´s using the same cluster ID, a RR will reject prefixes received from a route reflector due to the loop avoidance mechanism. Therefore, you have less redundancy in comparison to use a different Cluster ID per RR. The drawback of using a different Cluster ID per RR is an increase in memory requirements due to the number of prefixes received (from Clients plus from RRs).

Hope this helps,

Jose.