Knowledge Base

Using Other Mail Server Software

Using Other Mail Server Software (Linux)

Plesk for Linux is shipped with the Postfix and Qmail mail
servers . For IMAP and POP3 delivery, Courier IMAP or Dovecot can be
used. We recommend that you use Dovecot instead of the default Courier
IMAP server. Dovecot is faster, more secure, and it consumes fewer
server resources and provides support for server-side mail filtering
rules.

You can switch between the mail servers in Tools & Settings >
Updates > Add/Remove Components > Mail hosting
features or in Tools & Settings > Mail Server Settings.

Plesk will start using the new mail server without any need for server
restart. You can select another mail server at any time later.

Notes on switching to Dovecot:

Dovecot comes with Piegeonhole –
server-side filtering engine, which can be configured from webmail
interface and third-party extensions to mail user agents (MUAs) like
Thunderbird.
Dovecot supports pushing email through “IMAP IDLE” and optional “IMAP
NOTIFY” protocol extensions.
Dovecot uses Sieve language to define
server-side filtering rules.
Due to high diversity of Dovecot versions in OS vendor repositories,
we build our own packages. Many Dovecot features that do not make
much sense in Plesk context are left out (the provided version is
built without their support).
Dovecot does not support short mail account names with Qmail and POP3
authorization before SMTP.
Switching back to Courier IMAP from Dovecot is not recommended,
especially if a large number of new email messages have been
received: This will cause re-downloading of email messages by mail
clients.
If you used SSL/TLS certificates with Courier IMAP, you can reuse
them with Dovecot. To do this, take either /usr/share/pop3d.pem
or /usr/share/imapd.pem file, and save it to
/etc/dovecot/private/ under the name ssl-cert-and-key.pem.
Make sure that the new file has the 0400 root:root permissions.
After that restart the Dovecot service.