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DNS not reset - jabubo - 09-09-2010 01:29 AM


when I submit a new test and set that it should do more than 1 test runs from that location, the second run benefits from the dns lookup of the first one.

Can you add a "ipconfig /flushdns" before any site lookup?


RE: DNS not reset - pmeenan - 09-09-2010 03:05 AM

The caching DNS service on windows is disabled on the test machines (so there's nothing to flush). What you are seeing is the upstream DNS servers at the ISP caching the responses for the TTL. If you're seeing responses under 50ms (for a DSL location) let me know, otherwise it's just an artifact of how DNS works.

Theoretically I could run Treewalk (bind port for windows) on the test machines themselves to eliminate all tiers of caching but that will tend to break some DNS-based geo-location services (like CDN POP localization) so there's not good answer.



RE: DNS not reset - jabubo - 09-09-2010 04:18 PM

Ok, thanks for that answer and for the great work!