I've been running Postfix / Dovecot for about 9 months on a CentOS system I maintain and use for shared hosting, and have been happy with it. However, there are two "features" that I'd really like to provide to my clients: 1) The ability to change their password, and/or add additional email addresses from inside a web interface 2) A better webmail interface (of course, most of my clients us Outlook and other desktop programs, but I need to offer them something useful online too).
Users can currently use Horde, but very few of my clients like the look & feel of it, and of course, there's no way to change one's password.
Yesterday, I launched a 2nd server to use for Nameserver redundancy purposes, as well as to migrate the mailserver over. I was looking at - and leaning towards - installing Zimbra, as I've actually used it before.
However, I didn't realized until now how much resource requirement it has. 1GB of RAM for a dedicated (VPS) mail server for only about 15-20 email accounts seems a bit much.
Are there any other good alternatives you guys would suggest, and/or modifications I could make to my current Postfix / Dovecot / Horde configuration on which to improve upon?