Question 280
An eBGP exchange has a route that the neighbor refuses to accept. Observed: The route appears locally but its next-hop address fails the remote peer's reachability checks. Which change-acceptance control is most relevant to preventing this exact failure?
Explanation
Correct Answer
The control is specific to the initial failure. It requires the result Remote neighbor installs and forwards through the authorized next hop. and treats The route appears locally but its next-hop address fails the remote peer's reachability checks. as a failure signal. The causal concern is the exported next-hop attribute is inappropriate for the external path.
Incorrect Answers
The proposed control is tied to route reflection only propagates paths according to client and nonclient advertisement rules, typically observed when some nonclient speakers still cannot learn routes from other nonclients. Here the target is the exported next-hop attribute is inappropriate for the external path; monitor remote neighbor installs and forwards through the authorized next hop.
This gate monitors a different failure, route-monitor output shows no vpnv4 capabilities agreed. It would not detect the current problem: The route appears locally but its next-hop address fails the remote peer's reachability checks. The appropriate check requires remote neighbor installs and forwards through the authorized next hop.
It is valid for another service scenario but checks another ibgp router receives the path but loses it when the originating client flaps. This case instead needs a gate for the route appears locally but its next-hop address fails the remote peer's reachability checks and evidence that remote neighbor installs and forwards through the authorized next hop.