I ran both command on the PowerShell server 2k12 & 2K16 and give the same result.
Please inform me if there is/are major or minor difference between both commands.
ipconfig /flushdns will flush the local computer cache. And dnscmd /clearcache will clear the dns server cache.
With the former you will clear the "local" cache of the server you work on. It will NOT clear the dns server cache. While with dnscmd you will clear the dns server cache.
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