JNCIP-SP: Juniper Networks Certified Professional – Service Provider (2021) — Question 8

You are troubleshooting a Layer 3 VPN issue. The VPN has been passing traffic successfully for some time, but now it is reported that traffic is no longer flowing.
You look into the bgp.l3vpn.0 table and see newly hidden routes.
What would be the cause of this problem?

Answer options

• A. The LSP used to connect the PE routers is down.
• B. The connection from the PE to the customer is down.
• C. The BGP routes received from the customer are no longer reachable.
• D. The family inet-vpn parameter was deleted from the BGP configuration of the PE router.

Correct answer: D

Explanation

The correct answer is D because if the family inet-vpn parameter is deleted from the BGP configuration, the PE router will no longer advertise or accept VPN routes, leading to hidden routes. Options A and B refer to physical connectivity issues, which would prevent traffic flow but not specifically cause routes to be hidden. Option C indicates reachability issues with customer routes, but does not directly relate to the hiding of routes in the BGP table.