Ask HN: What is a good open source mail server for Linux?
What would you recommend for a good open source mail server that uses IMAP and SMTP so I can setup a webmail client and use Thunderbird on?
What would you recommend for a good open source mail server that uses IMAP and SMTP so I can setup a webmail client and use Thunderbird on?
But if you're serious about it then start with learning Postfix as your MTA. This will only be good for inbound mail and delivering mail to local inboxes. If you want IMAP and POP3 then you'll need to dig into some other services. Courier is the most popular, but all the glue will still need to be written by you.
And you are saying Courier is better than Dovecot?
Unfortunately, all Open Source webmail clients I know of (including Redcube, Horde) are cumbersome if you have used Gmail and Fastmail.
My setup is qmail (SMTP) + vmailmgr + Dovecot (IMAP) and it was pretty easy to set up.
To start with qmail, I would recommend http://www.lifewithqmail.org/
PS. Citadel isn't very pretty looking so if you are just using it for webmail, I would suggest installing roundcube on top of it (you can setup the web admin to use a different port and still run apache/nginx for your site)
Edit: Oh, and courier-imap. It's so little hassle I haven't touched it in years and forgot how it's set up.
Unless you really know Exim well I would recommend to keep "Debian's magic configuration stuff". It makes it easy to set up SSL/TLS:
http://wiki.debian.org/Exim#TLS_and_Authentication
Setting up dovecot is pretty straight forward, too:
https://www.debian-administration.org/article/275/
Note: I see no reason to enable imap -- just go with imaps.
Greylisting for exim:
http://www.debian-administration.org/articles/167
Both Exim and dovecot can use a separate password file (among other options) for "virtual" users. I just use pam-auth for imap, and separate auth for smtp -- imap does give access to user files anyway (at least in principle, it could probably be locked more down).
If you're new to Exim, there's no big reason not to use postfix -- other than it's the default for Debian (Postfix being default on Ubuntu).
If you're going to host a lot of virtual users -- you might benefit from dbmail -- I haven't tried it myself, but been following the project from the sidelines for a few years -- it appears to be a good solution for virtual-user email (email users that are not also system users):
[1] I'll be dist-upgrading "soon" -- hopefully nothing will break ;-)
edit: formatting