Learn / Network Operations and Design / Diagnosis in Practice In this module ✓ Narrow a fault from its scope before running any command ✓ Say what each diagnostic tool rules in and rules out ✓ Choose the test whose either outcome halves the search space ✓ Apply one method across four domains in a single sitting Activities ○ ≡ Lesson
What the symptom already tells you
Who is affected, what still works, when it started - and what each tool actually proves.
11 min
○ ? Quiz
Knowledge check - the troubleshooting method
Seven questions on narrowing a fault, choosing a test and reading a result. Method rather than protocol.
8 min
○ ★ Assessment
Diagnostic capstone
Four faults from four domains, in one sitting - a route that affects one destination, a filter applied in the wrong direction, a lease handing out the wrong gateway, and a circuit that is slow rather than down. You have met each of them before, in the module that taught its topic; the point here is reaching for the method rather than for the module.
90 min
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