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Routing decision : More specific path vs. better metric

This site is running BGP. 

Say router1 is advertising 10.1.0.0/16 and router2 is advertising 10.1.8.0/22. Router2 is going to be satellite, and router1 will be a fast terrestrial connection. They also both have cellular backup, and the route is prepended via route-map out the cell link to make the main WAN link more desirable. The reason for this is that router2's site was going to be part of router1's site, but the link between them couldn't be acquired. 

What will happen to traffic bound for 10.1.8.0/22 in this situation; will the more specific route from router2 still be the winner? Will it still work that way when router1 has its main connection running and router2 is on the cellular?

1 Reply 1

Jon Marshall
Hall of Fame
Hall of Fame

The most specific prefix is always the winner before anything else.

AD, BGP attributes, metrics come into the decision but only if the prefixes are the same.

Jon