In BGP (Border Gateway Protocol), when evaluating multiple routes to the same destination, the first attribute that is considered is the local preference value. The local preference is a BGP attribute used to influence outbound routing decisions within an Autonomous System (AS).
Step-by-Step Breakdown:
Local Preference:
The local preference attribute is used to determine which path is preferred for traffic leaving the AS. The higher the local preference value, the more preferred the route.
BGP Path Selection:
The BGP path selection process evaluates the following attributes in this order:
Local Preference (higher is preferred)
AS Path (shorter is preferred)
Origin (IGP > EGP > incomplete)
MED (Multi-Exit Discriminator) (lower is preferred)
Juniper Reference:
BGP Path Selection: In Junos, the local preference attribute is the first to be evaluated when determining the best path for outbound traffic.