The installation and configuration of Dovecot on Linux systems

The installation from source code

The installation from a repository

The configuration of Dovecot for IPv6 support

To install Dovecot from source code - download it from the official vendor site:  http://www.dovecot.org/download.html . 

Next log into the superuser.

Unpack the downloaded content using a command:
tar xzf name_of_dowloaded_dovecot.tar.gz
Next go to directory of where Postfix is unpacked. Enter the command:
make
Then use a command:
make install

The installation from a repository:

apt-get install dovecot-common

yum install dovecot-common

zypper install dovecot-common

To enable the IPv6 support, edit dovecot file (usually in /etc/dovecot).

Find the line with "listen". The default value is * (asterisk) like below:

To enable listening on IPv6 adressen, after the "listen" definition add specific IPv6 addresses in square brackets e.g."listen = *, [2001:db8::15]" . If dovcot should listen on every address on ports 110 and 143 (:::110 i :::143) add "[::]" after a comma as below:

After restart of Dovecot, check if it listens on specific ports and addresses (110 - POP3, 143 - IMAP)
netstat -ano | grep :110
and
netstat -ano | grep :143