Free Cisco SPRI 300-510 Actual Exam Questions - Question 6 Discussion
communication problems between the two instances. Which description of the possible cause of
issues in the routing domain is true?
Option C makes sense too—if the NSEL values don’t match, neighbors won’t come up, so communication between instances fails even if everything else looks fine.
Maybe B. Different IS-IS instances act like separate routing domains, so they don’t talk to each other unless there’s some special configuration. That would explain communication problems between the two. A seems less likely because usually interfaces can be configured for more than one IS-IS instance if needed, and D sounds like a Cisco-specific command that wouldn’t broadly cause this kind of problem. C is possible but the question points more to the fact that these are two distinct instances not forming routes.
B/C? Different IS-IS instances usually don’t exchange routes, so B makes sense. But if the NSEL values don’t match, neighbors won’t form, which fits C. I’d drop A and D though.
Maybe A, interfaces generally shouldn’t be in two IS-IS instances simultaneously.
It’s B, different IS-IS instances don’t share routing info by default.
A seems off because interfaces can be in multiple instances with proper config. I’d rule that out and focus more on B or C since neighborship and instance isolation are common issues.
B/C? I’ve seen IS-IS instances named differently often don’t talk to each other, so B sounds right. But also missing NSEL config (C) can cut neighborships. Not fully sure here.