Re: [exim] POP/IMAP and Exim (4.43)

On Mon, Jul 18, 2005 at 10:28:17PM +0200, Robert Cates wrote:
> Hi,
>
> it probably seems like a very obvious answer to my questions, but I'm just
> not experienced enough to know how these servers tie-in and work together...
>
> I have Courier and Exim installed and things seem to work ok, but I
> apparently do not have AUTHentication setup/configured, at least not with
> Exim. I've compiled Exim myself and included AUTH_CRAM_MD5=yes
> AUTH_PLAINTEXT=yes AUTH_SPA=yes, but when I 'telnet localhost 25' I do not
> get '250-AUTH PLAIN LOGIN CRAM-MD5'.
>
> And now to my questions - do I have to configure AUTHentication in Exim, in
> Courier, or both? Do I even need POP/IMAP servers with Exim, and if not,
> what would be a situation where I'd want POP/IMAP servers running?
>
> As I see it, POP/IMAP servers are there to act as the front-end to the MTA
> for MUAs, which is why I'm wondering if I even need to configure
> AUTHentication in Exim, but I'm just not sure.

Exim is an SMTP MTA so its job is to deliver email to a file. Mail arrived
from the Internet for a local user and is put in their account on the
machine.

Courier is an IMAP (and POP) MTA so its job is to retrieve (amongst other
things) mail from a file. Email clients which support IMAP can be configured
to read this mail from the server. These clients don't have to use your SMTP
server to send email if it is not appropriate.

SMTP is not, by default, authenticated. Nor is it necessary to be so. SMTP
was designed pre-spam and in the Good Ole Days everyone trust (and knew)
everyone else on the Internet.

You still don't need to configure Authenticated SMTP unless you have a
specific requirement (i.e. some people who aren't Local to your mail system
or domain and want to send email as if they were.)

This is grossly simplified, but there is no intent to patronise if you
already know all this.

The details depend very much on your sitation and what you are trying to
achieve.

Mike

--
Mike Richardson
60% Networks / 40% Messaging and Collaboration
IT Services
Email: mike.richardson@???
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