← Computer Networks learning pathComputer Networks · Module 9 of 10
Troubleshooting networks
Diagnose connectivity problems step by step.
📖 Key ideas
- Start at the physical layer: cables, lights, Wi-Fi signal.
- Check IP settings: ipconfig / ip a.
- Test reachability: ping gateway, then external IP, then domain.
- Trace paths: tracert/traceroute.
- Check DNS: nslookup/dig.
💡 Real-life example: Troubleshooting is checking a water pipe from the tank to the tap, one joint at a time.
ipconfigShows Windows IP settings
pingTests reachability
tracertShows route hops
nslookupQueries DNS