Lesson 12: Network Troubleshooting
Week of Tue, Dec 1 · lesson closes Mon, Dec 7
Take Meerk's quiz for Lesson 12
This lesson's items
Exact due times are in Canvas.
Watch — Professor Messer
Watch — Professor Messer: Troubleshooting (N10-009)
Free, independent educational resource. Not affiliated with or endorsed by CompTIA. Watch, then read the notes below.
Know these cold
- Troubleshooting model: Identify → Establish theory → Test theory → Establish action plan → Implement → Verify → Document.
- Systematic ping sequence: 127.0.0.1 → own IP → gateway → remote IP → remote hostname.
- Tools: ping (ICMP reachability), tracert/traceroute (path), nslookup/dig (DNS), netstat (connections), arp (ARP cache), ipconfig/ifconfig (IP config), cable tester (Layer 1).
Meerk's quiz — open the Lesson 12 gate
10 questions, no time limit. 85% on your first attempt in a 24-hour window opens the gate. Retakes inside the window are practice — they help you learn, they don't count. Work alone; the point is to know it, not to have seen it.
Dinner Table Question
Ask at home: A user says 'the internet is broken' — what are the first three questions you would ask them?
En español: Un usuario dice que 'el internet está roto' — ¿cuáles serían tus primeras tres preguntas?