What are two possible causes for EIGRP Stuck-In-Active routers? (Choose Two)

A. Some query or reply packets are lost between the routers.

B. The neighboring router starts receiving route updates from this router.

C. A failure causes traffic on a link between two neighboring routers to flow in only one direction (unidirectional link).

D. The neighboring router stops receiving ACK packets from this router.








 

Suggested Answer: AC

Generally, a route shown as Active is going to be there for a very short period of time by the time you repeat the command, hopefully that Active route has gone
Passive. Sometimes that doesnt happen, though, and the route becomes SIA - Stuck In Active.
A route becomes SIA when a query goes unanswered for so long that the neighbor relationship is reset. From experience, I can tell you that troubleshooting SIA routes is more of an art form than a science, but there are four main reasons a route becomes SIA:
The link is unidirectional, so the query cant possibly be answered. The queried routers resources are unavailable, generally due to high CPU utilization. The queried routers memory is corrupt or otherwise unable to allow the router to answer the query.
The link between the two routers is of low quality, allowing just enough packets through to keep the neighbor relationship intact, but not good enough to allow the replies through.
To sum it up, routes generally become SIA when a neighbor either doesnt answer a query, or either the query or reply took a wrong turn somewhere. I told you it wasnt the easiest thing to troubleshoot!

This question is in 300-101 Cisco Implementing Cisco IP Routing (ROUTE) Exam
For getting Cisco Certified Network Professional (CCNP) Routing and Switching Certificate




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