Why are the interfaces missing?

Scenario

Refer to the topology. Your company has connected the routers R1. R2. and R3 with serial links. R2 and R3 are connected to the switches SW1 and SW2, respectively. SW1 and SW2 are also connected to the routers R4 and R5.

The EIGRP routing protocol is configured.

You are required to troubleshoot and resolve the EIGRP issues between the various routers.

Use the appropriate show commands to troubleshoot the issues.

The loopback interfaces on R4 with the IP addresses of 10.4.4.4 /32, 10.4.4.5/32. and 10.4.4.6/32 are not appearing in the routing table of R5

Why are the interfaces missing?
A . The interfaces are shutdown, so they are not being advertised.
B . R4 has been incorrectly configured to be in another AS, so it does not peer with R5.
C . Automatic summarization is enabled, so only the 10.0.0.0 network is displayed.
D . The loopback addresses haven’t been advertised, and the network command is missing on R4.

View Answer

Answer: B

Explanation:

For an EIGRP neighbor to form, the following must match:

– Neighbors must be in the same subnet

– K values

– AS numbers

– Authentication method and key strings

Here, we see that R4 is configured for EIGRP AS 2, when it should be AS 1.