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ENARSI Exam - Question 67


Refer to the exhibit.

Exam ENARSI Question 67Exam ENARSI Question 67

AS111 is receiving its own routes from AS200 causing a loop in the network.

Which configuration provides loop prevention?

Show Answer
Correct Answer: B

To prevent AS111 from receiving its own routes from AS200 and causing a loop, it is essential to disable the 'allowas-in' command for the relevant neighbors. The 'allowas-in' command allows the router to accept routes that contain its own AS number in the AS_PATH, which is the root cause of the loop. By disabling 'allowas-in' for both neighbors 195.1.1.1 and 195.1.2.2, AS111 will reject routes containing its own AS number, thus preventing the looping problem.

Discussion

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MasoudGhorbaniOption: B
Feb 28, 2024

the allowas-in command is used to allow prefixes to be received by the router even if they contain its own AS number in the AS_PATH. the best option is to stop accepting routes containing AS111's own AS number

Colmenarez
Sep 3, 2023

This reminds me of an encore lab question.

Carl1999
Feb 2, 2022

B is correct. In this case, Allow as-in is not needed. Because it disables control of AS_PATH.

xziomal9Option: B
Apr 29, 2022

The correct answer is: B router bgp 111 no neighbor 195.1.1.1 allowas-in no neighbor 195.1.2.2 allowas-in

[Removed]Option: B
Jul 17, 2024

B is correct