Hello,
I wish to set up a linux smtp relay. The relay will not have pop or imap on it. I want it to be able to relay mail to the internet from local people and relay mail addressed to local people from the internet, disallowing all other relaying.


my setup will be like this
smtp.mydomain.com mx <---- note others do not have mx records
pop.mydomain.com pop3 server,
imap.mydomain.com webmail server with only 25 clients

I also want to relay mail based on username, with the majority going to one email server.

All my clients have smtp.mydomain.com as their smtp sending in their mail user agents. All internet traffic only sees my mx record for smtp.mydomain.com.

joe@foreigndomain.com sends email to bob@mydomain.com it gets picked up by smtp.mydomain.com and then sent to either pop.mydomain.com or imap.mydomain.com based on user rules.

My question is what would be the easiest way to set this up? What mail server should i use? qmail? postfix? I am using rh9 on the smtp.mydomain.com host.

Any hints or links to howtos would be greatly appreciated.
thank you

Does your DNS information properly list smtp.mydomain.com as the 'MX' record for the mydomain.com domain? This is probably the first step.

Also, where will the mail be delivered to before it is picked up? Why can't one machine handle both pop and imap? Forwarding mail delivery based on the method of pickup (POP/IMAP) is kind of a strange way of doing it...

If you absolutely need these three services (SMTP/POP/IMAP) on separate hosts, I suggest that you simply make the /var/spool/mail folder available to the other two pop and imap hosts via a secured NFS implimentation. That way, you won't need to relay anything any where: Messages addressed to bob@mydomain.com will be delivered directly to smtp.mydomain.com, where they will live until they are deleted.

When your users want to get their mail, they connect to either imap.mydomain.com or pop.mydomain.com which will access the mail sitting on smtp.mydomain.com via NFS.

hi thanks for your reply
yes my dns is listing smtp as an mx record. it is a running environment for over 500 accounts. 5 domains.

The reason it has to be this way (two seperate mail retrievers) is that my company wants to put up exchange but not convert the entire company. They want to test it for a few users,
but they dont want to test it in a real test invironment but using their own emails/domains etc.

it is almost purely a windows shop, i just started here and i am trying to put in linux solutions where they fit. so no nfs either.
so everything has to kinda work... since it is live.