Getting Transit Packets on Router
If we use debug ip packet on Cisco router, we can only see the packets that originated on the router or destinated to the router. We cannot see any transit packets. The reason is, in the interface level, the command ip route-cache is enabled as default. We can define route-cache options to NetFlow or CEF. On the most cases, route-cache is using CEF because ip cef is enabled on the global.
Therefore, we need to type no ip route-cache in interface level to let all transit IP packet to pass through processor.
