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I was trying to set up a mail server with no luck. I want it to accept mail from authenticated users only and deliver them. I want the users to be able to connect over the internet. Ideally the mail server wouldn't accept any incoming mail. Essentially I want it to accept messages on a receiving port and transfer them to the intended recipient out port 25.

If anyone has some good links and guides that would be awesome. I am quite familiar with linux but have never played around with MTA's and am currently running debian 6.

More Specific Problem!

Sorry, that was general and postfix is complex.

I am having trouble enabling the submission port with encryption and authentication.

What Works:

  • Sending mail from the local machine. (sendmail
  • Ports are open. (25 and 587)
  • Connecting to 587 appears to work, I get a "need to starttls" warning and starttls appears to work.

But when I try to connect with the next command I get the error below.

# openssl s_client -connect localhost:587 -starttls smtp
depth=0 /CN=localhost.localdomain
verify error:num=18:self signed certificate
verify return:1
depth=0 /CN=localhost.localdomain
verify return:1
Certificate chain
 0 s:/CN=localhost.localdomain
Server certificate
No client certificate CA names sent
SSL handshake has read 1605 bytes and written 354 bytes
New, TLSv1/SSLv3, Cipher is DHE-RSA-AES256-SHA
Server public key is 2048 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
    Protocol  : TLSv1
    Cipher    : DHE-RSA-AES256-SHA
    Session-ID: E07926641A5EF22B15EB1D0E03FFF75588AB6464702CF4DC2166FFDAC1CA73E2
    Master-Key: 454E8D5D40380DB3A73336775D6911B3DA289E4A1C9587DDC168EC09C2C3457CB30321E44CAD6AE65A66BAE9F33959A9
    Key-Arg   : None
    Start Time: 1349059796
    Timeout   : 300 (sec)
    Verify return code: 18 (self signed certificate)
250 DSN

If I try to connect from evolution I get the following error:

The reported error was "HELO command failed: TCP connection reset by peer".
share|improve this question
Have you decided on which MTA you'd like to use? Instructions will vary heavily depending on which one you're using. – Benjamin Barenblat Sep 30 '12 at 20:05
I have been trying to configure postfix but I haven't committed to any one yet (is there another popular one?). – Kevin Cox Oct 1 '12 at 0:09

As you are referring Postfix it is unclear to me if you already read the documentation at all?!

The basic configuration gives you everything you need for the first steps. Then go ahead with some standard configurations. If you are done with them, come back with a more concrete question.

Otherwise I have to state: Yes this is truly feasible and can be done very easily (if you read the documentation)

share|improve this answer
I did read the documentation a number of times. I am going to wipe what I have and start again to see if I can get it working. – Kevin Cox Oct 1 '12 at 0:10

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