Hi I'm posting this on several mail-related newsgroups to try to get as
much information as I can I hope no one regards this as a spam:
I would like to host mail for a single domain (ie all users should be
[EMAIL PROTECTED]) on several (geographically distributed) machines,
with users in each area receiving their mail at the local mail sever. The
hard part is, as bandwidth is a limiting issue, I don't want all the mail
to be forwarded through a single host (eg if user1 at location A is
sending a 5 MB attachement to user2 at location B, I don't want that to
have to bounce off some central mail sever at location C). This means
that all the mail servers serve the same domain name but have to be
distinguishable (via DNS or sonmething sendmail does) by users served.
It seems to me that this must be do-able since AOL and other large
multinationals can't have all their mail go through some central
hub. However since DNS won't resolve different hosts according to user
name (since it knows nothing about the user sending/receiving the
mail) the SMTP protocol must have some way of routing beyond DNS (ie so we
can have one mail server which tells outside mail servers which
internal mail server to send a particular message to accorind to user name
-- without actually receiveing the message proper itself). This would
require some kind of pre-sending negotiation between mail servers. Is
such a thing possible?
Does any of what I've said make sense to anybody, and if so can you clue
me in on how to do this (or where to look to find out more).
I've found some stuff about using qmail + PH that looks like it might be
what I'm looking for (its a user address table thing that works with mail
daemons) -- does anyone know more about this.
Thank a lot in advance,
Sheer
