— Exhibit –
— Exhibit —
Click the Exhibit button.
ISP-A is advertising the 200.0.3.0/24 route to R1. R1 is advertising this BGP route to R2 but the
route is hidden on R2.
Referring to the exhibit, which statement is correct about the 200.0.3.0/24 route?
A.
The route is unusable because the next hop is not reachable from R2.
B.
The route is unusable because it has not been verified.
C.
The route is hidden because R1 is changing the next hop to 192.168.16.1.
D.
The route is hidden because R2 has a more preferred route.
what a trick question.
technically it is A, but C is part true.
The Route is hidden b/c R1 is changing the next hop to 192.168.16.1….which also happens to be a route that it cant get to…(A)
this helped me understand.
https://www.nanog.org/meetings/nanog27/presentations/juniper.pdf
The correct answer is A.
The route shows as hidden and unusable since the next hop is not reachable from R2, this is the expected default behavior when an EBGP is sending a route learned from another EBGP to an IBGP, it does not change the next hop.
In order to make this work you can configure next-hop self on R1, this way R1 will change the next hop for this route to itself.
The point here is that even if you change the next-hop for the route thought a policy or using the next-hop self command the route is hidden because R2 does not have a valid NH to reach this network.
-“Meditation is the medicine of the mind”