Lesson 9: Network Troubleshooting
Week of Tue, Nov 10 · lesson closes Mon, Nov 16
Take Meerk's quiz for Lesson 9
This lesson's items
Exact due times are in Canvas.
Watch — Professor Messer
Watch — Professor Messer: Network Troubleshooting (220-1201)
Free, independent educational resource. Not affiliated with or endorsed by CompTIA. Watch, then read the notes below.
Know these cold
- Systematic troubleshooting: ping 127.0.0.1 → ping gateway → ping external IP (8.8.8.8) → ping hostname (google.com).
- APIPA (169.254.x.x) = DHCP unreachable. DNS failure = can ping IP but not hostname. Duplicate IP = two devices same address.
- Tools: ping (ICMP, reachability), tracert/traceroute (path), nslookup (DNS), netstat (connections), ipconfig /all (IP config).
Meerk's quiz — open the Lesson 9 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: If your internet stops working, what is the first thing you should check — and why?
En español: Si se cae tu internet, ¿qué es lo primero que deberías revisar — y por qué?