When is Poison Reverse used?
By default I thought in Cisco routers the implemented split horizon is with poison reverse.
So I expected to see that after R2 receives from R1 a route with a certain metric M1, the R2 would advertise back to R1 the same route but with metric 16.
However what I observed is different:
- either the router R2 didn't advertise back the route at all
- or the router R2 advertised back to R1 the route but with the same metric M1 (this latter case was when R1 received that route from another router R3, but with metric M1-1)
Do I miss something?