Re: Question about Qmail relating to MX retry processing

[Marc Perkel <marc@perkel.com>]

Harald Hanche-Olsen wrote:
> + "Pawel Panek" <pawel.panek@inet.pl>:
>
> | So if message is rejected (even temporaily) why not to try next MX
> | (as RFC 974 said)? Is Qmail following the specs or it is not?
>
> Actually, RFC 974 is obsoleted by RFC 2821, so people should quote it
> instead.  (Though RFC 974 was the relevant one when qmail was
> written.)
>
> As to why qmail does what it does, there was an extremely brief
> discussion on the qmail mailing list on 1996-06-25, and an equally
> brief discussion on comp.protocols.tcp-ip in the days before.
>
>   
> http://groups.google.com/group/comp.mail.misc/browse_frm/thread/8987d5e1c3c4698f/9eaefb25953624c6?lnk=st&q=&rnum=1#9eaefb25953624c6
>
> Nobody seemed to care much about the question back then.  If I were to
> guess, I'd say that djb chose what he did from the reasoning that
> backup MXs are there to deal with a host being down, and of course a
> host being down will not accept a connection.  (Hosts were probably
> down a lot more in those days.)
>
> Be that as it may, changing qmail's behaviour on this issue would
> probably be nontrivial, due to the way responsibility is divided up
> between qmail-send and qmail-remote.
>
> - Harald
>   
Perhaps the question needs to be revisited because the world have 
evolved since them. 1996 was before spam was invented. :)