Diagnose name resolution with nslookup
Diagnose a name-resolution fault by clearing the DNS resolver cache, looking up the host name, and querying a known-good internal DNS server for comparison. This page teaches a job procedure. These are not exam questions, this is not a score predictor, and nothing here is taken from any certification exam.
The steps on this page are free to read. The hands-on lab for this procedure is included with Academy.
Steps
- 1
Run ipconfig /flushdns to clear stale or negative entries from the DNS resolver cache.
- 2
Run nslookup intranet.corp.example and review the configured server and returned address.
- 3
Run nslookup intranet.corp.example 192.0.2.54 and compare the known-good internal server's answer with the first lookup.
What you should see
The resolver cache reports a successful flush. Both nslookup commands show a Server and Address header followed by the name and address for intranet.corp.example.