Separate address, routing, DNS, port, and application problems instead of guessing
Goal
You should be able to demonstrate the result described in the lesson and explain why each step was necessary.
You should be able to demonstrate the result described in the lesson and explain why each step was necessary.
Step-by-step
01
Check the interface address
Use ip addr to confirm the expected LAN address.
02
Check the route
Use ip route to confirm a default gateway exists.
03
Test the gateway
Ping or otherwise test the local router before testing the Internet.
04
Test DNS separately
Use dig or resolvectl to distinguish name-resolution problems from connectivity problems.
05
Check listening ports
Use ss -lntup to see whether the expected service is actually listening.
Verify before moving on
You should be able to demonstrate the result described in the lesson and explain why each step was necessary.
You should be able to demonstrate the result described in the lesson and explain why each step was necessary.
Troubleshooting
If a command or screen differs from the lesson, stop and verify the version you are using before forcing a change.
What you learned
You now understand the purpose of this part of the system and have a concrete result you can verify before continuing to the next lesson.