See the previous tutorial for SSL creation for SMTP.
Q. How do I configure Dovecot IMAPS and POP3s server using SSL certificate? Can I use SSL certificates generated for Postfix mail server?
A. Dovecot is an IMAP server for Linux/UNIX-like systems, written with security primarily in mind. It also contains a small POP3 server. It supports mail in either of maildir or mbox formats.
You need to enable POP3s and IMAPS. Open default configuration file:
# vi /etc/dovecot.conf
Make sure POP3S and IMAPS are enabled:
protocols = imaps pop3s
Next you must set PEM encoded X.509 SSL/TLS certificate and private key. They’re opened before dropping root privileges, so keep the key file unreadable by anyone but root (see how create certificate CSR and configure certificates for Postfix):
ssl_cert_file = /etc/postfix/ssl/smtp.theos.in.crt
ssl_key_file = /etc/postfix/ssl/smtp.theos.in.key
If key file is password protected, give the password using ssl_key_password directive:
ssl_key_password = myPassword
Save and close the file. Restart Dovecot server:
# /etc/init.d/dovecot restart