Refer to the exhibit.
A Boston company bought the assets of a New York company and is trying to route traffic between
the two data networks using EIGRP over EoMPLS. As a network consultant, you were asked to
verify the interoperability of the two networks.
From the show ip route command output, what can you tell the customer about the traffic flow
between the subnet in New York (172.16.8.0/24) and the subnets in Boston (172.16.16.0/24 and
10.10.16.0/24)?
A.
Traffic is flowing between the 172.16.8.0 subnet and subnets 172.16.16.0 and 10.10.16.0 and
no configuration changes are needed.
B.
Auto-summary must be disabled on N1 and B1 before traffic can flow between the 172.16.8.0
subnet and subnets 172.16.16.0 and 10.10.16.0.
C.
Traffic will flow between the 172.16.8.0 subnet and 172.16.16.0 without any further
configuration changes. However, auto-summary must be disabled on N1 and B1 before traffic can
flow between the 172.16.8.0 subnet and the 10.10.16.0 subnet.
D.
Auto-summary must be disabled on N1 and B1 before traffic can flow between the 172.16.8.0
subnet and the 172.16.16.0 subnet. However, traffic will flow between the 172.16.8.0 subnet and
10.10.16.0 without any further configuration changes.
Explanation:
Basically auto route summarization happens at the classful network boundary…so
that would make N1 and B1 the locations that summarization would occur for the 172.16.0.0/16
classful networks.
So if you left auto-summarization enabled on those 2 routers, you would have an issue with
discontiguous networks being advertised by both routers N1 and B1 with their classful mask
(172.16.0.0/16 and 10.0.0.0/8), which will cause you issues.
Turning off auto-summarization on N2 and B2 wouldn’t make any difference, as their networks
wouldn’t be summarized due to the fact that they are not meeting a classful boundary on their
perspective routers.