An outage occurred after a software upgrade on core switching.

Comprehensive and Detailed Explanation From Exact Extract:

According to the structured troubleshooting methodology outlined in the CNX-001 objectives, once a potential root cause is identified (in this case, a suspected firmware bug), the next step is to test the theory to confirm the cause before taking action. This helps prevent misdiagnosis and unnecessary configuration changes.

Relevant Extract from CompTIA CloudNetX CNX-001 Study Guide — under “Structured Troubleshooting Methodology”:

“After identifying symptoms and forming a theory of probable cause, the next step is to test the theory to verify it is the actual cause of the problem.”

Other options:

A. Establishing a plan of action comes after confirming the cause.

C. Documenting lessons learned is the final step.

D. Implementing the solution should only occur after the issue is confirmed.

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