Free Cisco 300-420 Actual Exam Questions - Question 7 Discussion
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?
This question is interesting, but I’d go with D here. Changing each interface to L1 or L2 individually lets you fine-tune where the router forms adjacencies and handles traffic, cutting CPU use without fully limiting the router’s capability. It’s more targeted than making the whole router just L1 or L2 like in C. Making the router strictly one level might work but could reduce flexibility in larger networks. So, D feels like a better balance between performance and functionality.
D Changing interfaces to either L1 or L2 can reduce the number of adjacencies and cut CPU usage, especially if the router doesn’t need to handle both levels everywhere. It’s more granular than just forcing the whole router to one level.
C seems right since splitting roles cuts CPU load more effectively than tweaking interfaces.
Option C feels more comprehensive since making the router strictly L1 or L2 cuts down on unnecessary processing, instead of just tweaking interface levels which might still keep some overhead.
Maybe D works better here since setting interface circuit types can limit unnecessary L1/L2 adjacencies and reduce overhead per link, instead of forcing the whole router to one level like in C.
C is simpler—dropping one level removes extra processing overhead on the router.
It’s D because setting interfaces as either L1 or L2 limits unnecessary protocol overhead on each link, which can reduce CPU and bandwidth usage more specifically than switching the whole router to just L1 or L2.
It’s C because running both L1 and L2 increases overhead; picking one level cuts down unnecessary processing and stabilizes the router’s load. D could help but doesn’t fully resolve the dual-level complexity.
Maybe D could help by reducing unnecessary traffic on certain interfaces, but I’m wondering if the question specifies what kind of traffic is causing the high CPU—like is it SPF calculations or just adjacency maintenance? Also, does it mention if both L1 and L2 neighbors are needed for the network design, or could they simplify by limiting to just one level? That might affect whether C or D is better. More context on network topology or the type of traffic spiking would be useful here.