A few times I've run across people putting IP addresses in as MX RRs for
sites. Unfortunately from a customer support point of view, sendmail
will actually deliver mail in this circumstance. I've dug through
various RFCs and the all I can find is a place in RFC974 where it says
several places that an MX shall refer to a host name. i.e.
.....For
the purposes of message routing, the system stores RRs known as MX
RRs. Each MX matches a domain name with two pieces of data, a
preference value (an unsigned 16-bit integer), and the name of a
host.
However, I can't find anywhere that specifically forbids it. This makes
it difficult when the customer is saying "but it works from my
(other/old) provider" Does anyone know why sendmail does support this
and is there any reason to consider making exim do the same?
My feeling is no, but as I say, it's a pain to try to explain to people
why sendmail works and smail and exim don't. I haven't tried to see if
qmail does or not.
--
Artificial Intelligence stands no chance against Natural Stupidity.
GAT d- -p+(--) c++++ l++ u++ t- m--- W--- !v
b+++ e* s-/+ n-(?) h++ f+g+ w+++ y*
