Re: How to declare port 143

On February 20, 2026 3:40:59 AM GMT+02:00, Steve Litt via dovecot <[email protected]> wrote:
>Hi all,
>
>I have Dovecot 2.4.2 working (plain text only) on my Qemu virtual
>machine, with Claws-Mail able to work with all its files. However, I
>want to declare the Dovecot server as running on Port 143, and when I
>do, I dovecot -F throws the error message shown later in this message.
>If I comment out the explicit port declaration, it works fine, and I
>want to know why. To the best of my knowledge, my declaration of port
>143 exactly matches your 2.4.2 documentation:
>
>The following is my attempt to tell Dovecot to serve *explicitly* at
>port 143:
>
>===============================================
># My Dovecot server will operate on Localhost
>listen = 127.0.0.1
>
>service imap {
>  inet_listener imap-login {
>    port = 143
>  }
>#  inet_listener imaps {
>#    port = 993
>#    ssl = yes
>#  }
>}
>===============================================
>
>The following is the result:
>
>===============================================
>[root@dovecotvoid ~]# dovecot -F
>doveconf: Fatal: Error in configuration file /etc/dovecot/dovecot.conf:
>duplicate listener: 143:127.0.0.1 [root@dovecotvoid ~]#
>===============================================
>
>If I comment out the port = 143, it works. Why is it griping about a
>duplicate listener? At the bottom of this email is the entire
>dovecot.conf and the result of dovecot -n, and there are no
>sub-configuration files in conf.d :
>
>
>===============================================
># Start new configs with the latest Dovecot version numbers here:
>dovecot_config_version = 2.4.2 # Must be current version
>dovecot_storage_version = 2.4.2 # Must be current version or earlier
>                                # 2.3 is minimum
>
># I only want imap
>protocols {
>  imap = yes
>  lmtp = no
>  pop3 = no
>}
>
># My Dovecot server will operate on Localhost
>listen = 127.0.0.1
>
>service imap {
>  inet_listener imap-login {
>    port = 143
>  }
>#  inet_listener imaps {
>#    port = 993
>#    ssl = yes
>#  }
>}
>
># mail_home is only for virtual users
># A virtual user is a user with no system account
># I have no virtual users, so I've commented out mail_home.
>#mail_home = /srv/mail/%{user}
>
># mail_driver is the storage format
>mail_driver = maildir
>
># mail_path is location of top of storage data
># WARNING: For troubleshooting be prepared to switch
># to literal location of ~
>mail_path = ~/mail/Maildir  # In my case
>
># mail_home is the home directory of the user identified as ~
># WARNING: system users have no ~ without it.
>mail_home = /home/slitt
>
># You need a log you can locate
># There might not be a 
>log_path=/var/log/dovecot.log
>
>
>#mail_uid = slitt
>#mail_gid = slitt
>mail_uid = vmail
>mail_gid = vmail
>
># By default first_valid_uid is 500. 
>#If your vmail user's UID is smaller,
># you need to modify this:
>#first_valid_uid = uid-number-of-vmail-user
>
>namespace inbox {
>  inbox = yes
>  separator = /
>}
>
># Authenticate as system users:
>passdb pam {
>   driver = pam
>   #driver = passwd
>}
>
>userdb passwd {
>  driver = passwd
>}
>
>#ssl_server_cert_file = /etc/dovecot/ssl-cert.pem
>#ssl_server_key_file = /etc/dovecot/ssl-key.pem
>===============================================
>
>
>
>
>The following is the output of dovecot -n:
>
>===============================================
># 2.4.2 (0962ed2104): /etc/dovecot/dovecot.conf
># OS: Linux 6.12.71_1 x86_64  
># Hostname: dovecotvoid
>dovecot_config_version = 2.4.2
>dovecot_storage_version = 2.4.2
>listen = 127.0.0.1
>log_path = /var/log/dovecot.log
>mail_driver = maildir
>mail_gid = vmail
>mail_home = /home/slitt
>mail_path = ~/mail/Maildir
>mail_uid = vmail
>protocols {
>  imap = yes
>  lmtp = no
>  pop3 = no
>}
>service imap {
>  inet_listener imap-login {
>    port = 143
>  }
>}
>namespace inbox {
>  inbox = yes
>  separator = /
>}
>passdb pam {
>  driver = pam
>}
>userdb passwd {
>  driver = passwd
>}
>
>===============================================
>_______________________________________________
>dovecot mailing list -- [email protected]
>To unsubscribe send an email to [email protected]
>


This is because of service imap-login. It already has listener for port 143. Adding it to service imap directly won't work. 

See `doveconf service/imap-login`

Aki

_______________________________________________
dovecot mailing list -- [email protected]
To unsubscribe send an email to [email protected]