[TriLUG] Email Setup

[Joseph Tate]

On Wed, 30 Mar 2005 17:17:42 -0500, Steve Hoffman <srhoffman at gmail.com> wrote:
> Been doing quite a bit of research on MTA's and retrieval daemons for
> email, but I wanted to know what other people are using.
> 
> We basically host email for several hundred domains and are using Exim
> as the MTA in mbox format with tpop3d to pick mail up, throw a little
> pop-before-smtp in there and viola...our setup.
> 
> Basically all I'm trying to do is add IMAP (timapd would have been
> perfect but doesn't exist yet) for these virtual users, but none of
> them seem to support mbox format or are configurable enough to use our
> current directory structure (ex /etc/virtual/domain.com/passwd,
> /var/spool/virtual/domain.com/user, etc)  So if I'm going to convert
> mailboxes then I might as well look into redoing the whole shebang!
> 
> So what can I use that's relatively easy to setup and very reliable
> for multiple domains.  Would prefer RPM based, since this will run on
> RHEL3, but I'll do source too.
> 
> TIA,
> Steve

I'd check out cyradm with cyrus for managing virtual domains.  Then
switch to LDAP for authorization/authentication.

For the MTA postfix works really well with virtual domains, and can be
set up to do pop before smtp if you must, but better yet, use SMTP
Auth over TLS or SMTPS.

What Cyrus gives you is a procmail-less easily configurable filtering
mechanism (SIEVE) as well as very efficient e-mail storage.  It also
has functionality for shared e-mail boxes and full posix-like ACLs. 
It's a fully pop3 and imap4 compliant server and has openssl support
built in for pop3s and imaps support.  You can use sasl or pam for
user auth, letting you use the same mechansim as you use for postfix
with SMTP Auth enabled.

The only hole in the postfix/cyrus combination is the integration of
spam filtering.  Spamassassin must pass through a python script in the
handoff between postfix and cyrus.  There may be a way to plug in
SIEVE, but with pure virtual users, there's no good way to do
auto-learning.  Of course I'm also leaning towards spam filtering on
the client rather than the server.  It seems like Thunderbird does a
much better job with it's bayesian filtering than SA does, though I
don't have any real numbers to back that up.


-- 
Joseph Tate
Personal e-mail: jtate AT dragonstrider DOT com
Web: http://www.dragonstrider.com