Designing Cisco Enterprise Networks (ENSLD) — Question 31

A router running ISIS is showing high CPU and bandwidth utilization. An engineer discovers that the router is configured as L1/L2 and has L1 and L2 neighbors.
Which step optimizes the design to address the issue?

Answer options

• A. Make this router a DIS for each of the interfaces
• B. Disable the default behavior of advertising the default route on the L1/L2 router
• C. Configure the router to be either L1 or L2
• D. Configure each interface as either L1 or L2 circuit type

Correct answer: D

Explanation

Configuring each interface as either L1 or L2 circuit type minimizes unnecessary complexity and traffic, thus reducing CPU and bandwidth usage. Making the router a DIS or disabling default route advertisement does not directly address the underlying issue of mixed L1 and L2 configurations. Changing the router to only L1 or only L2 would not take full advantage of its capabilities as a dual-mode router.