BGP Path Selection
BGP can receive multiple advertisements for the same route from multiple sources. BGP selects only one path as the best path. After the path is selected, BGP puts it in the IP routing table and propagates the path to its neighbors. BGP uses the following criteria, in the order listed, to select a path for a destination:
Ignore a route if the next hop is not known.
Ignore IBGP routes that are not synchronized.
Prefer the route with the largest weight.
Prefer the route with the largest local preference.
Prefer the route that was locally originated.
Prefer the route with the shortest AS path. If you're using bgp bestpath as-path ignore, skip this step. When you use the as-set option for aggregated routes, it counts as 1 regardless ...
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