CCNA EIGRP Troubleshooting Sim

By | July 18, 2017

This is an Updated  CCNA exam question (2016). You might see a different IP addressing, Port allocation and Configurations.

As usual, take time and read through the question so as to clearly understand what Cisco want you to do.

Note: This  CCNA EIGRP Troubleshooting Sim are used for demonstration only,you might find slight different in IP addressing, Port allocation in the real CCNA exam. But it all works the same way if you could just grasp the technique.

I suggest you use packet tracer for practice.

If you need a refresher, Read EIGRP Explained with Examples

The network topology below is running EIGRP. You are required to troubleshoot and resolve the EIGRP issues between the various routers. Use the appropriate show commands to troubleshoot the issues.

Question 1
Why are the two loopback interfaces on R4 ( & not showing in the routing table of R5?

A. The two loopback interfaces are shutdown.
B. By default, automatic summarization is enabled, so only the network is shown.
C. R4 has been incorrectly configured in another AS, so it does not form neighbor adjacency with R5.
D. The ‘network’ command is missing in the configuration of R4 so the loopback addresses haven’t been advertised.

Answer: C
On close examination, R4 was configured with AS 2 (router eigrp 2) while other routers are using AS 1 (router eigrp 1). so R4 so it does not form neighbor adjacency with R5.
Question 2
A user on R1 wants to send data to R5. Which path are the packets sent?
A. Packets from R1 to R5 will go through R2.
B. Packets from R1 to R5 will go through R3.
C. Packets are equally load-balanced over R2 and R3.
D. Packets are unequally load-balanced over R2 and R3.

Answer: A
To find out the answer to this question, use the show ip route command to view the R1’s routing table. You might likely see something similar to this below:

Now, on R5 take a closer look at the following three interfaces:
Each of them were advertised via ; this shows that traffic from R1 to R5 goes through R2

Question 3
Why does R1 not form EIGRP neighbor relationship with R6?
A. K values are mismatched.
B. The AS does not match.
C. A network command is missing.
D. Passive-interface is configured.

Answer: C
From the configuration of R6 we learn that R6 is missing “network” command (the network between R1 & R6) under EIGRP so EIGRP neighbor relationship will not be formed between them.

Question 4
Refer to the following output on R1:

Why can R1 not reach with source
A. R5 is missing a network statement.
B. The loopback interface on R5 is shut down.
C. R1 is missing a network statement.
D. Incorrect IP address configured on the Loopback 1 interface on R5.

Answer: C
R1 is missing an eigrp network statement of its loopback 0 ( , so there wont be any advertisement of that network and a ping to destination (R5) from will not be successful because R5 does not know how to reply to R1.