In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server.
POP version 3 (POP3) is the version in common use.
In computing, the Internet Message Access Protocol (IMAP) is an Internet standard protocol used by email clients to retrieve email messages from a mail server over a TCP/IP connection. IMAP is defined by RFC 3501.
IMAP was designed with the goal of permitting complete management of an email box by multiple email clients, therefore clients generally leave messages on the server until the user explicitly deletes them. An IMAP server typically listens on port number 143. IMAP over SSL (IMAPS) is assigned the port number 993.
Virtually all modern e-mail clients and servers support IMAP, which along with the earlier POP3 (Post Office Protocol) are the two most prevalent standard protocols for email retrieval. Many webmail service providers such as Gmail, Outlook.com and Yahoo! Mail also provide support for both IMAP and POP3.
# yum install dovecot
# cd /etc/dovecot # ll drwxr-xr-x. 2 root root 4096 17 nov 02:28 conf.d -rw-r--r--. 1 root root 4380 30 apr 2018 dovecot.conf
dovecot.conf doesn't need editing.
several files must be edited.
# cd /etc/dovecot/conf.d ll -rw-r--r--. 1 root root 5296 23 jun 2017 10-auth.conf -rw-r--r--. 1 root root 1893 30 apr 2018 10-director.conf -rw-r--r--. 1 root root 3062 30 apr 2018 10-logging.conf -rw-r--r--. 1 root root 17579 30 sep 17:58 10-mail.conf -rw-r--r--. 1 root root 3383 30 apr 2018 10-master.conf -rw-r--r--. 1 root root 2486 30 sep 17:59 10-ssl.conf -rw-r--r--. 1 root root 1668 30 apr 2018 15-lda.conf -rw-r--r--. 1 root root 2808 23 jun 2017 15-mailboxes.conf -rw-r--r--. 1 root root 4235 30 apr 2018 20-imap.conf -rw-r--r--. 1 root root 936 23 jun 2017 20-lmtp.conf -rw-r--r--. 1 root root 4065 30 apr 2018 20-pop3.conf -rw-r--r--. 1 root root 676 23 jun 2017 90-acl.conf -rw-r--r--. 1 root root 292 23 jun 2017 90-plugin.conf -rw-r--r--. 1 root root 2597 30 apr 2018 90-quota.conf # vi 10-auth.conf disable_plaintext_auth = no # vi 10-mail.conf mail_location = maildir:~/.maildir # vi 10-ssl.conf ssl_cert = </etc/pki/tls/certs/example.com.crt ssl_key = </etc/pki/tls/private/example.com.key ssl_ca = </etc/pki/tls/certs/example.com_ca-bundle.pem
# systemctl start dovecot # systemctl enable dovecot
firewall-cmd --permanent --add-port=143/tcp firewall-cmd --permanent --add-port=993/tcp firewall-cmd --permanent --add-port=110/tcp firewall-cmd --permanent --add-port=995/tcp firewall-cmd --reload