/etc/dovecot

Dovecot is a popular open-source IMAP and POP3 server for Unix-like operating systems. It is known for its security and performance features. Configuration for Dovecot is done via various files located in the /etc/dovecot/ directory. Here's a detailed overview of the key configuration files and their usage:

Key Dovecot Configuration Files

1. /etc/dovecot/dovecot.conf

   • Purpose: This is the main configuration file for Dovecot. It includes basic settings and other configuration files.

   • Key Settings:

     • listen: Specifies the IP addresses to listen on.

     • protocols: Specifies which protocols (IMAP, POP3, etc.) Dovecot should support.

     • mail_location: Defines where the mailboxes are located.

   • Example:

     listen = *
     protocols = imap pop3
     mail_location = maildir:~/Maildir

2. /etc/dovecot/conf.d/10-auth.conf

   • Purpose: Configures authentication settings for Dovecot.

   • Key Settings:

     • auth_mechanisms: Specifies the authentication mechanisms to use (e.g., plain, login, digest-md5, cram-md5).

     • !include auth-sql.conf.ext: Includes additional configuration files for SQL-based authentication.

   • Example:

     auth_mechanisms = plain login

3. /etc/dovecot/conf.d/10-ssl.conf

   • Purpose: Configures SSL/TLS settings for secure communication.

   • Key Settings:

     • ssl: Whether SSL is enabled (yes or no).

     • ssl_cert: Path to the SSL certificate.

     • ssl_key: Path to the SSL key.

   • Example:

     ssl = yes
     ssl_cert = </etc/ssl/certs/dovecot.pem
     ssl_key = </etc/ssl/private/dovecot.key

4. /etc/dovecot/conf.d/10-master.conf

   • Purpose: Configures master process settings and services.

   • Key Settings:

     • service imap-login: Settings for the IMAP login service.

     • service pop3-login: Settings for the POP3 login service.

     • service auth: Settings for the authentication service.

   • Example:

     service imap-login {
       inet_listener imap {
         port = 0
       }
       inet_listener imaps {
         port = 993
         ssl = yes
       }
     }

5. /etc/dovecot/conf.d/10-mail.conf

   • Purpose: Configures mail storage settings.

   • Key Settings:

     • mail_location: Specifies the format and location of mail storage (e.g., maildir, mbox).

     • mail_privileged_group: Group with access to mail directories.

   • Example:

     mail_location = maildir:~/Maildir
     mail_privileged_group = mail

6. /etc/dovecot/conf.d/10-logging.conf

   • Purpose: Configures logging settings.

   • Key Settings:

     • log_path: Path to the log file.

     • info_log_path: Path to the info log file.

   • Example:

     log_path = /var/log/dovecot.log
     info_log_path = /var/log/dovecot-info.log

7. /etc/dovecot/conf.d/20-lmtp.conf

   • Purpose: Configures the LMTP (Local Mail Transfer Protocol) settings.

   • Key Settings:

     • service lmtp: Settings for the LMTP service.

   • Example:

     service lmtp {
       unix_listener /var/spool/postfix/private/dovecot-lmtp {
         mode = 0666
         user = postfix
         group = postfix
       }
     }

8. /etc/dovecot/conf.d/20-auth-sql.conf.ext

   • Purpose: Configures SQL-based authentication.

   • Key Settings:

     • driver: SQL driver (e.g., mysql, pgsql).

     • connect: Connection string to the database.

   • Example:

     driver = mysql
     connect = host=localhost dbname=mail user=mailuser password=secret

Example Workflow

1. Edit Main Configuration File:

   sudo nano /etc/dovecot/dovecot.conf

2. Configure Authentication:

   sudo nano /etc/dovecot/conf.d/10-auth.conf

3. Set Up SSL/TLS:

   sudo nano /etc/dovecot/conf.d/10-ssl.conf

4. Define Mail Storage:

   sudo nano /etc/dovecot/conf.d/10-mail.conf

5. Restart Dovecot Service:

   sudo systemctl restart dovecot

Conclusion

Dovecot’s configuration is highly modular, with different aspects of the service managed in separate files within the /etc/dovecot/ directory. Understanding and configuring these files allows for tailored mail server setups with appropriate security, authentication, and logging configurations. Regularly reviewing and updating configurations ensures a secure and efficient mail server environment.