BGP route selection doesnt respect local preference

This article outlines the problem of BGP route selection broken in certain code version and how could one find that they are affected.

In 9.3 and 9.4, due to an uninitialized variable being used to select the best route among all routes for the same prefix, random route selection may happen.
This may lead a bgp running router to select the route with lowest local preference.

Following output is one symptom that would arise

 

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James Palmer

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