Test DNS resolution safely Guided Practice

Lab brief

Know the problem and the evidence you need

The situation

The device appears connected, but websites fail to open or report that names cannot be resolved.

Your finished record

A DNS-versus-connectivity test record

Determine whether basic internet reachability works independently of domain-name resolution.

Why this matters

Testing an IP destination and a domain separately distinguishes a DNS problem from a wider connectivity failure and prevents unnecessary router resets.

Safety and setup

Prepare before changing anything

Have this ready

Do not disable security software or the firewall for this lab.
Do not replace router or device DNS settings until the comparison tests are recorded.
Use well-known test destinations and avoid entering private internal hostnames into public tools.

Field checks

Run the lab

Complete one check at a time. Record the evidence before moving on.

0 of 5 checks complete

Check 1 of 5 Confirm the local link first Do thisVerify that the active adapter is connected and the local gateway is present. Record thisA usable local connection before DNS is tested.
Check 2 of 5 Test local gateway reachability Do thisUse a permitted gateway test and record reachable, unreachable or blocked. Record thisA local-boundary result that prevents mislabeling a Wi-Fi failure as DNS.
Check 3 of 5 Test a known internet IP address Do thisUse a trusted public test IP with ping or another permitted connectivity check and record the result. Record thisEvidence of internet reachability that does not depend on DNS.
Check 4 of 5 Test a known domain name Do thisUse a browser, nslookup, dig or the operating system resolver for a known public domain. Record thisA successful resolution, timeout or resolver error recorded exactly.
Check 5 of 5 Compare the three boundaries Do thisCompare gateway, internet-IP and domain-name results and note where the first failure occurs. Record thisA boundary-based conclusion rather than a DNS guess based on one website.

Interpret results

Match the evidence to the next action

If you seeNext action

Gateway and internet IP work but domain names fail

DNS is a strong candidate; record the configured resolver and check provider/router resolver status before changing it.

The gateway works but the internet IP fails

Investigate router WAN or provider connectivity rather than DNS.

Only one website fails

Treat it as a site, browser, cache or filtering issue until broader resolution tests also fail.

Decision point

Choose the next action

Change a DNS setting only after the comparison isolates resolution, record the original setting, and repeat the same domain test after the reversible change.

Completion

Confirm the evidence you produced

Finished record: A DNS-versus-connectivity test record

I tested the local gateway before DNS.
I compared an internet IP with a domain name.
I identified the first failed boundary and recorded the exact message.

I recorded the evidence and selected a next action.