CentOS - Aug 2014 - Postfix setup

I'm trying to clarify the various ways in which I could set up
Postfix + Dovecot + SpamAssassin under CentOS-7,
and I'd welcome any comments on the following remarks.

As far as I can see there are 3 standard ways of setting this up:
  1. Use amavisd
  2. Use dovecot + pigeonhole/sieve
  3. Use spamass-milter

At present I'm following (2), but am thinking of going over to (1),
since this seems simpler.
(Amavisd wasn't available when I set up CentOS-7, so I didn't consider
it
then.)

It seems to me that (2) is using dovecot in a slightly odd way,
since as far as I can see dovecot normally takes email from ~/Maildir/cur/
and then moves marked spam.

I'm not quite sure if (3) is a genuine alternative,
or if it is why it is not the standard since it seems very simple?

-- 
Timothy Murphy  
e-mail: gayleard /at/ eircom.net
School of Mathematics, Trinity College, Dublin 2, Ireland

On 08/25/2014 03:52 PM, Timothy Murphy wrote:
> I'm trying to clarify the various ways in which I could set up
> Postfix + Dovecot + SpamAssassin under CentOS-7,
> and I'd welcome any comments on the following remarks.
>
> As far as I can see there are 3 standard ways of setting this up:
>    1. Use amavisd
>    2. Use dovecot + pigeonhole/sieve
>    3. Use spamass-milter
>
> I'm not quite sure if (3) is a genuine alternative,
> or if it is why it is not the standard since it seems very simple?
>
I'm on CentOS 6 (well, actually Amazon AMI which is sort of somewhere in 
between CentOS 6 and CentOS 7) and I find (3) to be the easiest option:

1) From EPEL, install "spamass-milter" and
"spamass-milter-postfix" RPMs

2) Modify /etc/sysconfig/spamass-milter to uncomment "EXTRA_FLAGS" and
adjust spam threshold to your liking

3) Add following line to /etc/postfix/main.cf:

         smtpd_milters = unix:/var/run/spamass-milter/postfix/sock

4) Make sure spamass-milter, postfix, etc. are running and set to start 
at boot, using chkconfig, service, and/or systemctl as appropriate.

-Greg