Hi there,

It would be helpful if the "machines to relay mail for" segment of
dpkg-reconfiguring exim4-config would accept FQDNs as well as IP
addresses. This would mean performing a look up each time a relay was
attempted, I guess.

Regards,

Chris

[...]

Hello,

it is already possible to enter host names in this dialogue. However
this breaks relaying if one of the listed FQDNs does not resolve anymore
(old entry, machine was shut down and removed).
http://www.exim.org/exim-html-current/doc/html/spec_html/ch-domain_host_address_and_local_part_lists.html

If we marked this as supported we would need to think about
+ignore_unknown, too.

cu andreas