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    DNS cache not working?

    DHCP and DNS
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    • P
      Paul47
      last edited by

      I was trying to see if the DNS forwarder would shorten the turn-around time on DNS resolution, so I turned on the forwarder and set my DNS to look at the opendns servers (and unchecked the overwrite). Then I did a Diagnostics>DNSLookup to google.com, etc.

      The first time 127.0.0.1 took 95ms or so but the second time it went to zero, which suggests the cache is working. But if I go back a few minutes later the lookup is back to 95ms or whatever, as if the cache is cleared right away. Seems like the cache should hang around longer than a few minutes.

      I am running 2.1 beta i386, the 03/31 snapshot.

      <later>Oh, one other thing. Is there some way to look at the cached values in tabular form? I looked around but couldn't find anything…</later>

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      • C
        cmb
        last edited by

        The cache is retained for the length of the TTL of the hostname you're looking up. That'll be anywhere from 1 second to 1 day depending. Google is 5 minutes.

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        • P
          Paul47
          last edited by

          Wow, that's shorter than I imagined. Thanks for responding…

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