Connected: An Internet Encyclopedia Breaking Ties (Internal Updates)

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If a local BGP speaker has connections to several BGP speakers in neighboring autonomous systems, there will be multiple Adj-RIBs-In associated with these peers. These Adj-RIBs-In might contain several equally preferable routes to the same destination, all of which were advertised by BGP speakers located in neighboring autonomous systems. The local BGP speaker shall select one of these routes according to the following rules:

  1. If the candidate route differ only in their NEXT_HOP and MULTI_EXIT_DISC attributes, and the local system is configured to take into account MULTI_EXIT_DISC attribute, select the routes that has the lowest value of the MULTI_EXIT_DISC attribute.

  2. If the local system can ascertain the cost of a path to the entity depicted by the NEXT_HOP attribute of the candidate route, select the route with the lowest cost.

  3. In all other cases, select the route that was advertised by the BGP speaker whose BGP Identifier has the lowest value.

Next: 9.2.2 External Updates

Connected: An Internet Encyclopedia Breaking Ties (Internal Updates)