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Difficulty: MediumTroubleshooting DNS and Name Resolution Services

A network administrator is systematically troubleshooting a client workstation that cannot resolve the internal domain name `app.company.local`. Arrange the following troubleshooting steps in the correct logical sequence, starting from local host verification to testing remote authoritative DNS resolution.

  1. 1Verify local IP configuration and assigned DNS server IP addresses using `ipconfig /all`.
  2. 2Inspect the local HOSTS file for static overrides and clear stale cache entries using `ipconfig /flushdns`.
  3. 3Perform a standard query using `nslookup app.company.local` to test resolution via the primary configured DNS server.
  4. 4Execute `nslookup app.company.local <authoritative_server_ip>` to query the authoritative DNS server directly.

Answer

The correct order of troubleshooting steps begins with verifying local network and DNS server configuration, followed by checking local client files and clearing local DNS cache, then testing name resolution against the configured local DNS server, and finally querying the authoritative DNS server directly.
A structured DNS troubleshooting approach moves logically from local host settings to client-side caching, local recursive server testing, and finally authoritative DNS server validation. Verifying IP configuration first ensures valid DNS servers are targeted. Flushing local cache removes client-side stale records. Querying the local DNS server tests normal client operation, while querying the authoritative DNS server isolates server-side record configuration.

Step-by-Step Solution

1
Verify client network settings using `ipconfig /all`.
Confirms the workstation has proper IP configuration and valid primary/secondary DNS server IP addresses assigned.
Troubleshooting must start at the local host level to eliminate basic IP configuration or missing DNS server assignment issues.
2
Check the `HOSTS` file and clear local DNS cache with `ipconfig /flushdns`.
Eliminates misconfigurations caused by static local overrides or outdated DNS entries cached on the host.
Local OS resolution checks the `HOSTS` file and local DNS resolver cache prior to querying network DNS servers.
3
Test name resolution using `nslookup app.company.local`.
Determines whether the client's configured default DNS server can successfully resolve the target hostname.
This tests the standard recursive query path used by client applications under normal operating conditions.
4
Query the authoritative DNS server directly using `nslookup app.company.local <authoritative_ip>`.
Isolates whether the record is missing on the authoritative server or failing due to intermediate recursion/forwarding/firewall issues.
Direct targeting of the authoritative server provides definitive confirmation of record existence and DNS zone health.

Key Concept

Systematic DNS Troubleshooting Methodology
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Topics

Troubleshooting DNS and Name Resolution Services

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