What happens to packets that are forwarded from the 13.0.0.0/8 network to the Null0 interface?

Refer to the following.
Router # sh ip route eigrp
13.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
D 13.0.0.0/8 is a summary, 00:00:32, Null0
What happens to packets that are forwarded from the 13.0.0.0/8 network to the Null0
interface?

Refer to the following.
Router # sh ip route eigrp
13.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
D 13.0.0.0/8 is a summary, 00:00:32, Null0
What happens to packets that are forwarded from the 13.0.0.0/8 network to the Null0
interface?

A.
Flagged

B.
Accepted

C.
Summarized

D.
Dropped

Explanation:
When an EIGRP router summarizes, it automatically builds a route to null0 for the
summarized route. The router to null0 prevents packets that do not match a specific entry in
the routing table from following a default route. (The route to null0 causes the packet to be
dropped).



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me

me

Explanation forgets to MENTION that the MORE Specific route is what is used.

The logical effect here matters as you may have discontiguous networks.

10.10.1.0 and 10.10.3.0 with a summary of 10.10.0.0/22

hence things destined for 10.10.0.x/24 and 10.10.2.0/24 would arrive at the router…but there IS NO MORE SPECIFIC route for those two blocks…so they’d match ONLY the summary and be NULL0 routed….on purpose: dumping the traffic so it does not clutter up the queue or waste processor time.

Iit makes a lot of functional sense when you chew on the thought a bit.