Hello,
Looking through the changes of Exim version 3.16 I see that number 24 states:
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24. Added an in-memory cache of DNS lookups that fail or give DNS failures
such as timeouts. This means that a message with many addresses at the same
domain that times out won't take an excessively long time to route. There is
no caching for successful lookups - we rely on resolver and name server
caching in that case.
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Does this refer to actual name server problems - for example ones giving
timeouts - or is this a form of negative-caching (whereby the DNS entry just
doesn't exist)? If the latter is this going to cause a problem for local
caching servers which use their own negative-caching? (I'm thinking aloud
here :-))
John.
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John Horne, University of Plymouth, UK Tel: +44 (0)1752 233914
E-mail: jhorne@???
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