[Dovecot] Excluding some system users after configuration

[Timo Sirainen]

On Thu, 2011-11-24 at 01:44 +0100, Nanitous wrote:
> Dear readers,
> 
> Consider an installed Postfix configuration (2.3.3) on CentOS.
> Now I want to install Dovecot (alas only version 1.0.7.7 is available) to provide IMAP services for a few system users, but not all. Most importantly the mail delivery by postfix for some of these system user /must/ not change after the installation of Dovecot.
> 
> How can I prevent the installation of Dovecot to touch some specific system user accounts?

As long as you don't configure Postfix to deliver mails via Dovecot's
"deliver", there is no change to how mails are delivered.

If you want to restrict IMAP access to only some users, you can do it
with pam_listfile: http://wiki.dovecot.org/Authentication/RestrictAccess