[ On , December 14, 2001 at 11:15:20 (+0000), Nigel Metheringham wrote: ]
> Subject: Re: [Exim] Administrivia - Christmas is coming, the autoreplies are getting fat
>
> which is the nub of it... is an autoreply a form of DSN or a stand alone
> message. My treatment of autoreplies is very much as a DSN varient.
Ah, but that's where you're wrong. The vacation-style autoresponse is
NOT a delivery status notification and it sure as heck does not happen
at the transport layer. I.e. it's got nothing whatsoever to do with
SMTP and thus should know nothing whatsoever about the SMTP envelope
sender address (though knowing how that address is translated into an
RFC-2822 header is useful so that one can use it to better detect what
messages should not be responded to).
There's zero conceptual difference between a user setting up a pipe to
vacation in their ~/.forward (or whatever mechanism is used with any
given mailer), and the user having a human secretary answer their e-mail
and reply with similar responses (the only differences are in the
implementation, eg. the secretary would likely be smarter about who to
reply to, would likely never get caught in a loop, and would know better
what to say in the reply and how to customise it to the recipient).
Vacation autoresponders are _user_ agents. They MUST reply as the user
would, _not_ as the MTA would.
> [you noticed the redundancy in my ruleset - it wasn't really accidental]
I didn't think it was an accident! ;-)
Mind you I don't think I've ever seen an autoresponder loop except when
I've been testing my version of vacation and had made a coding bug (I
had to shut down one of the MTAs involved and clean the queue
manually!). Perhaps that's because most mailers I run are delivering to
POP/IMAP mailboxes and which never themselves offer vacation-like tools
to the users. I've seen what I suspect are autoresponder loops passing
through some of the outbound relay machines, but they never seem to have
too much detrimental effect on an intermediate machine, even when the
local user involved is on a high-speed broadband connection.
--
Greg A. Woods
+1 416 218-0098; <gwoods@???>; <g.a.woods@???>; <woods@???>
Planix, Inc. <woods@???>; VE3TCP; Secrets of the Weird <woods@???>
