This is a KB which provides document path for PBR/FBF configuration.

There are no symptoms as this is a query from customer reg new implementation.

Below is the doc detailing PBR or FBF (filter-based forwarding).

https://www.juniper.net/us/en/research-topics/what-is-policy-based-routing.html

Below is the doc for the config example.

https://www.juniper.net/documentation/us/en/software/junos/routing-policy/topics/example/filter-based-forwarding-example.html