[CentOS] Kind of OT: internal imap server

Thu Aug 24 13:12:17 UTC 2006
Les Mikesell <lesmikesell at gmail.com>

On Thu, 2006-08-24 at 01:51, Feizhou wrote:

> Let's get one thing straight. I have not used exim yet but I dare say 
> that sendmail is the most flexible mta program available thanks to its 
> ruleset feature. However, this power is limited to those who can think 
> in sendmail rulesets and given your comment about nobody edits 
> sendmail.cf anymore, I guess it shows how hard it is to get mastery of 
> sendmail's power.

But you are missing the point that once something has been done
for sendmail via the included m4 macros, no one else ever has
to understand it again. You just edit a line in the .mc file
to activate the feature/option following the comments in the
file or some documentation and the right thing happens.  As
shipped in Centos you can do pretty much anything you would
want a mailer to do by changing a few lines in sendmail.mc.
It doesn't make any more sense to talk about the difficulty
of understanding sendmail.cf than it does to talk about
source code changes.  It is nice that both are available for
those who might want to tackle changes at that level but it
is not necessary for ordinary use.

Then when you add MimeDefang, you also get the ability to
add in any other operations you want to happen in parallel
with the smtp chat and control it all with a bit of perl.

> As for mimedefang, qmail lets you do anything that can be described in 
> perl, shell, C, python, whatever you fancy in fact and reject at the 
> smtp level too since you can replace qmail-queue or put a filter before 
> qmail-queue.

Another way of saying that is that qmail is so bad you have to
completely replace components to make it usable at all.

> I am sorry, but one can get the functionalily of sendmail sans the 
> neverending list of security updates and that is on two other mta software.

Sendmail is probably the most heavily audited code available
today, and none of the other MTA+addons are as well integrated
or designed for efficiency as sendmail+MimeDefang with its
multiplexed pool of backend slaves.  Qpsmtpd is promising but
the project is still in the process of reinventing things
MimeDefang has had down for years.

-- 
  Les Mikesell
   lesmikesell at gmail.com