On Wed, 12 Dec 2001, Greg Ward wrote:
> > what is exim using for domain lookups? does exim cache it?
>
> It uses whatever your /etc/resolv.conf specifies. AFAIK Exim does not
> cache DNS results; that's what caching DNS servers are for.
Absolutely correct. However, _within a single process_, Exim does cache
failed DNS lookups such as timeouts. This is so that if it is routing a
message with a large number of recipients at the same domain, and this
domain's DNS lookup times out, it doesn't take an enormous amount of
time to complete the routing. Exim does not cache successful DNS
lookups at all.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
