On Mon, 30 Jun 2003, Thomas Tonino wrote:
> In chapter 11.8, I read:
> The calling host matches the list in host_lookup. The default for this option is
> *, so it must be changed if any lookups are to be avoided.
>
> I read this as: when I leave this out of the config, it will be *, and lookups
> will be done
Thanks for the report; that is indeed wrong. The description that is
given for the host_lookup option itself (in 13.22) is right: the default
is unset in the binary - it is in the *default configuration* that
"host_lookup=*" appears.
> But it isn't, so name lookups aren't done. It turns out that setting it to *
> also makes $sender_host_name available as ACL variable. Which is good for
> customizing error messages.
But costs you a DNS lookup for every incoming message.
> The ACL stuff is really nice. So flexible and powerful... thanks!
Glad you like it.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
Get the Exim 4 book: http://www.uit.co.uk/exim-book