Part 3: PostfixAdmin – Create Virtual Mailboxes on Debian 11/10 Mail Server

In previous articles, we discussed how to set up your own mail server on Debian from scratch. In part 1 and part 2 of this tutorial series, we learned how to set up Postfix SMTP server and Dovecot IMAP server, but so far we can only have email addresses for users with local Unix account. This tutorial is going to show you how to create virtual mailboxes on Debian mail server with PostfixAdmin, which is an open-source web-based interface to configure and manage a Postfix-based email server for many domains and users.

With virtual mailboxes, we don’t need to create local Unix account for each email address. If you are going to set up a mail server for a company or organization, it’s always better to have an easy way to create virtual mailboxes in a web-based interface, which also allows users to change their passwords. That’s where PostfixAdmin comes in.

PostfixAdmin Features

  • manage mailboxes, virtual domains, and aliases
  • vacation/out-of-office messages (Personally I think this feature is better done in Roundcube Webmail.)
  • alias domains (forwarding one domain to another with recipient validation)
  • users can manage their own mailbox (change alias, password, and vacation message)
  • quota support for single mailboxes and total quota of a domain
  • fetchmail integration: You can fetch emails from your original email address to your new email address.
  • command line client postfixadmin-cli for those who don’t want to click around in a web interface 😉

Note: Once you finish part 3, you can no longer use local Unix accounts as email addresses. You must create email addresses from the PostfixAdmin web interface.

Requirements

I assume that you have followed part 1 and part 2 of this tutorial series. If you followed mail server tutorials on other websites, I recommend purging your configurations (sudo apt purge postfix dovecot-core) and start over with my tutorial series, so you are not going to be confused by different setup processes.

Once the above requirements are met, let’s install and configure PostfixAdmin.

Step 1: Install MariaDB Database Server

PostfixAdmin is written in PHP and requires a database (MySQL/MariaDB, PostgreSQL or SQLite). This article will use MariaDB database, which is a drop-in replacement for MySQL. It is developed by former members of MySQL team who are concerned that Oracle might turn MySQL into a closed-source product. Enter the following commands to install MariaDB on Debian.

sudo apt update

sudo apt install mariadb-server mariadb-client

After it’s installed, MariaDB server should be automatically started. Use systemctl to check its status.

systemctl status mariadb

Sample output:

 mariadb.service - MariaDB 10.5.12 database server
     Loaded: loaded (/lib/systemd/system/mariadb.service; enabled; vendor preset: enabled)
     Active: active (running) since Fri 2021-10-29 23:44:59 EDT; 1min 12s ago
       Docs: man:mariadbd(8)
             https://mariadb.com/kb/en/library/systemd/
    Process: 435260 ExecStartPre=/usr/bin/install -m 755 -o mysql -g root -d /var/run/mysqld (code=exited, status=0/SUCCESS)
    Process: 435261 ExecStartPre=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)
    Process: 435263 ExecStartPre=/bin/sh -c [ ! -e /usr/bin/galera_recovery ] && VAR= ||   VAR=`cd /usr/bin/..; /usr/bin/galera_recovery`; [ $? -eq 0 ]   && systemctl set-environment _WSREP_START_POSITIO>
    Process: 435322 ExecStartPost=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)
    Process: 435324 ExecStartPost=/etc/mysql/debian-start (code=exited, status=0/SUCCESS)
   Main PID: 435310 (mariadbd)
     Status: "Taking your SQL requests now..."
      Tasks: 9 (limit: 1095)
     Memory: 78.7M
        CPU: 741ms
     CGroup: /system.slice/mariadb.service
             └─435310 /usr/sbin/mariadbd

If it’s not running, start it with this command:

sudo systemctl start mariadb

To enable MariaDB to automatically start at boot time, run

sudo systemctl enable mariadb

Now run the post-installation security script.

sudo mysql_secure_installation

When it asks you to enter MariaDB root password, press Enter key as the root password isn’t set yet. Your root account is already secured, so you should answer n to not set password.

debian bullseye secure mariadb

Next, you can press Enter to answer all remaining questions, which will remove anonymous user, disable remote root login and remove test database. This step is a basic requirement for MariaDB database security. (Notice that Y is capitalized, which means it is the default answer. )

install mariadb debian bullseye

Step 2: Download PostfixAdmin on Debian Server

PostfixAdmin is included in the default Debian repository. However, I don’t recommend it for the following reasons:

  • It can create problems when you upgrade the Ubuntu system to a new version, resulting in upgrade failure.
  • If you use Nginx, the postfixadmin package might automatically install Apache on your system.
  • If you use MySQL, this package might remove MySQL from your system.
  • The default postfixadmin package has a login loop issue from time to time.

So I will show you how to install the latest version of PostfixAdmin. Go to PostfixAdmin Gitbub page to download the latest version. You can use the wget tool to download it from command line. The download link is always available in the format below. If a new version comes out, simply replace 3.3.11 with the new version number.

sudo apt install wget

wget https://github.com/postfixadmin/postfixadmin/archive/postfixadmin-3.3.11.tar.gz

Once downloaded, extract the archive to the /var/www/ directory and rename it to postfixadmin.

sudo mkdir -p /var/www/

sudo tar xvf postfixadmin-3.3.11.tar.gz -C /var/www/

sudo mv /var/www/postfixadmin-postfixadmin-3.3.11 /var/www/postfixadmin

Step 3: Setting Up Permissions

PostfixAdmin requires a templates_c directory, and the web server needs read and write access to this directory, so run the following commands.

sudo mkdir /var/www/postfixadmin/templates_c

sudo apt install acl
sudo setfacl -R -m u:www-data:rwx /var/www/postfixadmin/templates_c/

Starting with Dovecot 2.3.11, the web server user needs permission to read Let’s Encrypt TLS certificate in order to do password hashing. Run the following two commands to grant permissions.

sudo setfacl -R -m u:www-data:rx /etc/letsencrypt/live/ /etc/letsencrypt/archive/

Step 4: Create a Database and User for PostfixAdmin

Log into MySQL/MariaDB shell as root with the following command.

sudo mysql -u root

Once you are logged in, create a database for PostfixAdmin using the following command. I named it postfixadmin, but you can use whatever name you like. (Don’t leave out the semicolon.)

create database postfixadmin;

Then enter the command below to create a database user for PostfixAdmin. This command also grants all privileges of postfixadmin database to the user. Replace postfixadmin_password with your preferred password. Note that the password should not contain the # character, or you might not be able to log in later.

grant all privileges on postfixadmin.* to 'postfixadmin'@'localhost' identified by 'postfixadmin_password';

Flush the privileges table for the changes to take effect and then get out of MariaDB shell.

flush privileges;

exit;

Step 5: Configure PostfixAdmin

The default PostfixAdmin configuration file is config.inc.php. We need to create a config.local.php file and add custom configurations.

sudo nano /var/www/postfixadmin/config.local.php

Add the following lines in the file, so PostfixAdmin can connect to MySQL/MariaDB database. Replace postfixadmin_password with the real PostfixAdmin password created in step 4.

<?php
$CONF['configured'] = true;
$CONF['database_type'] = 'mysqli';
$CONF['database_host'] = 'localhost';
$CONF['database_port'] = '3306';
$CONF['database_user'] = 'postfixadmin';
$CONF['database_password'] = 'postfixadmin_password';
$CONF['database_name'] = 'postfixadmin';
$CONF['encrypt'] = 'dovecot:ARGON2I';
$CONF['dovecotpw'] = "/usr/bin/doveadm pw -r 5";
if(@file_exists('/usr/bin/doveadm')) { // @ to silence openbase_dir stuff; see https://github.com/postfixadmin/postfixadmin/issues/171
    $CONF['dovecotpw'] = "/usr/bin/doveadm pw -r 5"; # debian
}

Save and close the file. Note that we will use the ARGON2I password scheme.

Step 6: Create Apache Virtual Host or Nginx Config File for PostfixAdmin

Apache

If you use Apache web server, create a virtual host for PostfixAdmin.

sudo nano /etc/apache2/sites-available/postfixadmin.conf

Put the following text into the file. Replace postfixadmin.example.com with your real domain name and don’t forget to set DNS A record for it.

<VirtualHost *:80>
  ServerName postfixadmin.example.com
  DocumentRoot /var/www/postfixadmin/public

  ErrorLog ${APACHE_LOG_DIR}/postfixadmin_error.log
  CustomLog ${APACHE_LOG_DIR}/postfixadmin_access.log combined

  <Directory />
    Options FollowSymLinks
    AllowOverride All
  </Directory>

  <Directory /var/www/postfixadmin/>
    Options FollowSymLinks MultiViews
    AllowOverride All
    Order allow,deny
    allow from all
  </Directory>

</VirtualHost>

Save and close the file. Then enable this virtual host with:

sudo a2ensite postfixadmin.conf

Reload Apache for the changes to take effect.

sudo systemctl reload apache2

Now you should be able to see the PostfixAdmin web-based install wizard at http://postfixadmin.example.com/setup.php.

Nginx

If you use Nginx web server, create a virtual host for PostfixAdmin.

sudo nano /etc/nginx/conf.d/postfixadmin.conf

Put the following text into the file. Replace postfixadmin.example.com with your real domain name and don’t forget to set DNS A record for it.

server {
   listen 80;
   listen [::]:80;
   server_name postfixadmin.example.com;

   root /var/www/postfixadmin/public/;
   index index.php index.html;

   access_log /var/log/nginx/postfixadmin_access.log;
   error_log /var/log/nginx/postfixadmin_error.log;

   location / {
       try_files $uri $uri/ /index.php;
   }

   location ~ ^/(.+\.php)$ {
        try_files $uri =404;
        fastcgi_pass unix:/run/php/php7.4-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include /etc/nginx/fastcgi_params;
   }
}

Note: Debian 11 ships PHP7.4 and Debian 10 ships with PHP7.3. If you use Debian 10, then change php7.4-fpm to php7.3-fpm in the above file.

Save and close the file. Then test Nginx configuration.

sudo nginx -t

If the test is successful, reload Nginx for the changes to take effect.

sudo systemctl reload nginx

Now you should be able to see the PostfixAdmin web-based install wizard at http://postfixadmin.example.com/setup.php.

Step 7: Install Required and Recommended PHP Modules

Run the following command to install PHP modules required or recommended by PostfixAdmin on Debian 11.

sudo apt install php7.4-fpm php7.4-imap php7.4-mbstring php7.4-mysql php7.4-json php7.4-curl php7.4-zip php7.4-xml php7.4-bz2 php7.4-intl php7.4-gmp

If you use Debian 10, run the following command.

sudo apt install php7.3-fpm php7.3-imap php7.3-mbstring php7.3-mysql php7.3-json php7.3-curl php7.3-zip php7.3-xml php7.3-bz2 php7.3-intl php7.3-gmp

Then restart Apache. (If you use Nginx, you don’t need to restart Nginx.)

sudo systemctl restart apache2

Step 8: Enabling HTTPS

To encrypt the HTTP traffic, we can enable HTTPS by installing a free TLS certificate issued from Let’s Encrypt. Run the following command to install Let’s Encrypt client (certbot) on Debian server.

sudo apt install certbot

If you use Apache, install the Certbot Apache plugin.

sudo apt install python3-certbot-apache

And run this command to obtain and install TLS certificate.

sudo certbot --apache --agree-tos --redirect --hsts --staple-ocsp --email [email protected] -d postfixadmin.example.com

If you use Nginx, then you also need to install the Certbot Nginx plugin.

sudo apt install python3-certbot-nginx

Next, run the following command to obtain and install TLS certificate.

sudo certbot --nginx --agree-tos --redirect --hsts --staple-ocsp --email [email protected] -d postfixadmin.example.com

Where

  • --nginx: Use the nginx plugin.
  • --apache: Use the Apache plugin.
  • --agree-tos: Agree to terms of service.
  • --redirect: Force HTTPS by 301 redirect.
  • --hsts: Add the Strict-Transport-Security header to every HTTP response. Forcing browser to always use TLS for the domain. Defends against SSL/TLS Stripping.
  • --staple-ocsp: Enables OCSP Stapling. A valid OCSP response is stapled to the certificate that the server offers during TLS.

The certificate should now be obtained and automatically installed, which is indicated by the message below.

postfixadmin ubuntu https

Step 9: Enable Statistics in Dovecot

PostfixAdmin needs to read Dovecot statistics. Edit the Dovecot configuration file.

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

Add the following lines to the end of this file.

service stats {
    unix_listener stats-reader {
    user = www-data
    group = www-data
    mode = 0660
}

unix_listener stats-writer {
    user = www-data
    group = www-data
    mode = 0660
  }
}

Save and close the file. Then add the web server to the dovecot group.

sudo gpasswd -a www-data dovecot

Restart Dovecot.

sudo systemctl restart dovecot

Step 10: Finish the Installation in Web Browser

Go to postfixadmin.example.com/setup.php to run the web-based setup wizard. First, you need to create a setup password for PostfixAdmin.

postfixadmin generate setup password

After creating the password hash, PostfixAdmin will display a line like below.

$CONF['setup_password'] = '$2y$10$58fIawuOb5y538RMBol/DOoqv2bJ7zhPRzRO.4Xq7MLeQJHmaFwF2';

You need to open the config.local.php file.

sudo nano /var/www/postfixadmin/config.local.php

Add the line displayed on PostfixAdmin setup page to the end of the file like below.

debian postfixadmin setup password

After saving the file, you need to refresh the PostfixAdmin setup page and enter the setup password again, then create the admin account.  Please don’t use a Gmail, Yahoo Mail, or Microsoft email address for the admin account, or you might not be able to log in later. Use an email address on your own domain. You can create the email address later in PostfixAdmin.

postfixadmin create superadmin account

Once the superadmin account is created, you can log into PostfixAdmin at postfixadmin.example.com/login.php.

postfixadmin login page debian

Step 11: Configure Postfix to Use MySQL/MariaDB Database

By default, Postfix delivers emails only to users with a local Unix account. To make it deliver emails to virtual users whose information is stored in the database, we need to configure Postfix to use virtual mailbox domains.

First, we need to add MySQL map support for Postfix by installing the postfix-mysql package.

sudo apt install postfix-mysql

Then edit the Postfix main configuration file.

sudo nano /etc/postfix/main.cf

Add the following lines at the end of this file.

virtual_mailbox_domains = proxy:mysql:/etc/postfix/sql/mysql_virtual_domains_maps.cf
virtual_mailbox_maps =
   proxy:mysql:/etc/postfix/sql/mysql_virtual_mailbox_maps.cf,
   proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_mailbox_maps.cf
virtual_alias_maps =
   proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_maps.cf,
   proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_maps.cf,
   proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_catchall_maps.cf

Where:

  • virtual_mailbox_domains points to a file that will tell Postfix how to look up domain information from the database.
  • virtual_mailbox_maps points to files that will tell Postfix how to look up email addresses from the database.
  • virtual_alias_maps points to files that will tell Postfix how to look up aliases from the database.

We want to use dovecot to deliver incoming emails to the virtual users’ message store, so also add the following line at the end of this file.

virtual_transport = lmtp:unix:private/dovecot-lmtp

Configure-Postfix-to-Use-MySQL-MariaDB-Database-ubuntu

Save and close the file. Next, we need to create the .cf files one by one. Create the sql directory.

sudo mkdir /etc/postfix/sql/

Create the mysql_virtual_domains_maps.cf file.

sudo nano /etc/postfix/sql/mysql_virtual_domains_maps.cf

Add the following content. Replace password with the postfixadmin password you set in Step 2.

user = postfixadmin
password = postfixadmin_password
hosts = localhost
dbname = postfixadmin
query = SELECT domain FROM domain WHERE domain='%s' AND active = '1'
#query = SELECT domain FROM domain WHERE domain='%s'
#optional query to use when relaying for backup MX
#query = SELECT domain FROM domain WHERE domain='%s' AND backupmx = '0' AND active = '1'
#expansion_limit = 100

Create the mysql_virtual_mailbox_maps.cf file.

sudo nano /etc/postfix/sql/mysql_virtual_mailbox_maps.cf

Add the following content.

user = postfixadmin
password = postfixadmin_password
hosts = localhost
dbname = postfixadmin
query = SELECT maildir FROM mailbox WHERE username='%s' AND active = '1'
#expansion_limit = 100

Create the mysql_virtual_alias_domain_mailbox_maps.cf file.

sudo nano /etc/postfix/sql/mysql_virtual_alias_domain_mailbox_maps.cf

Add the following content.

user = postfixadmin
password = postfixadmin_password
hosts = localhost
dbname = postfixadmin
query = SELECT maildir FROM mailbox,alias_domain WHERE alias_domain.alias_domain = '%d' and mailbox.username = CONCAT('%u', '@', alias_domain.target_domain) AND mailbox.active = 1 AND alias_domain.active='1'

Create the mysql_virtual_alias_maps.cf file.

sudo nano /etc/postfix/sql/mysql_virtual_alias_maps.cf

Add the following content.

user = postfixadmin
password = postfixadmin_password
hosts = localhost
dbname = postfixadmin
query = SELECT goto FROM alias WHERE address='%s' AND active = '1'
#expansion_limit = 100

Create the mysql_virtual_alias_domain_maps.cf file.

sudo nano /etc/postfix/sql/mysql_virtual_alias_domain_maps.cf

Add the following content.

user = postfixadmin
password = postfixadmin_password
hosts = localhost
dbname = postfixadmin
query = SELECT goto FROM alias,alias_domain WHERE alias_domain.alias_domain = '%d' and alias.address = CONCAT('%u', '@', alias_domain.target_domain) AND alias.active = 1 AND alias_domain.active='1'

Create the mysql_virtual_alias_domain_catchall_maps file.

sudo nano /etc/postfix/sql/mysql_virtual_alias_domain_catchall_maps.cf

Add the following content.

# handles catch-all settings of target-domain
user = postfixadmin
password = postfixadmin_password
hosts = localhost
dbname = postfixadmin
query = SELECT goto FROM alias,alias_domain WHERE alias_domain.alias_domain = '%d' and alias.address = CONCAT('@', alias_domain.target_domain) AND alias.active = 1 AND alias_domain.active='1'

Since the database passwords are stored in plain text so they should be readable only by user postfix and root, which is done by executing the following two commands.

sudo chmod 0640 /etc/postfix/sql/*
sudo setfacl -R -m u:postfix:rx /etc/postfix/sql/

Next, we need to change the value of the mydestination parameter in Postfix. Display the current value:

sudo postconf mydestination

Sample output:

mydestination = $myhostname, linuxbabe.com, localhost.$mydomain, localhost

The mydestination parameter contains a list of domain names that will receive emails delivered to local Unix accounts. In part 1, we added the apex domain name (like linuxbabe.com) to mydestination. Since we are going to use virtual mailbox, we need to remove the apex domain name from the list by issuing the following command.

sudo postconf -e "mydestination = \$myhostname, localhost.\$mydomain, localhost"

Now let’s open the Postfix main configuration file again.

sudo nano /etc/postfix/main.cf

Add the following lines at the end of this file.

virtual_mailbox_base = /var/vmail
virtual_minimum_uid = 2000
virtual_uid_maps = static:2000
virtual_gid_maps = static:2000

The first line defines the base location of mail files. The remaining 3 lines define which user ID and group ID Postfix will use when delivering incoming emails to the mailbox. We use the user ID 2000 and group ID 2000.

Save and close the file. Restart Postfix for the changes to take effect.

sudo systemctl restart postfix

Next, we need to create a user named vmail with ID 2000 and a group with ID 2000.

sudo adduser vmail --system --group --uid 2000 --disabled-login --no-create-home

Create the mail base location.

sudo mkdir /var/vmail/

Make vmail as the owner.

sudo chown vmail:vmail /var/vmail/ -R

Step 12: Configure Dovecot to Use MySQL/MariaDB Database

We also need to configure the Dovecot IMAP server to query user information from the database. First, run the following command to add MySQL support for Dovecot.

sudo apt install dovecot-mysql

Then edit the 10-mail.conf file.

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

In part 2, we used the following mail_location. Email messages are stored under the Maildir directory under each user’s home directory.

mail_location = maildir:~/Maildir

Since we are using virtual mailbox domain now, we need to enable mail_home for the virtual users by adding the following line in the file, because virtual users don’t have home directories by default.

mail_home = /var/vmail/%d/%n/

virtual mailbox home directory

Save and close the file. Then edit the 10-auth.conf file.

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

In part 2, we used the following value for auth_username_format.

auth_username_format = %n

The %n would drop the domain if it was given. Because in part 2 we were using local Unix account for the username of every email address, we must use %n to drop the domain, so users were able to login with the full email address.

Now we are using virtual mailbox domains, which means the username of every email address includes the domain part, so we need to change the auth_username_format as follows. %u won’t drop away the domain. This allows users to login with the full email address.

auth_username_format = %u

Uncomment the following line at the end of this file, so Dovecot can query user information from MySQL/MariaDB database.

!include auth-sql.conf.ext

Now you probably don’t want local Unix users to send emails without registering email addresses in PostfixAdmin, then comment out the following line by adding the # character at the beginning, so Dovecot won’t query the local /etc/passwd or /etc/shadow file.

#!include auth-system.conf.ext

It can be helpful to add the following two lines in this file to debug login issues. The login errors would be logged into /var/log/mail.log file. (Once users can login without problems, you can comment out the following two lines.)

auth_debug = yes
auth_debug_passwords = yes

dovecot mysql Password database

Save and close the file.

Edit the dovecot-sql.conf.ext file.

sudo nano /etc/dovecot/dovecot-sql.conf.ext

Here is the content that you should have in this file. By default, all lines in this file are commented out, so you can simply copy and paste them at the bottom. Replace postfixadmin_password with the postfixadmin password you set in Step 2.

driver = mysql

connect = host=localhost dbname=postfixadmin user=postfixadmin password=postfixadmin_password

default_pass_scheme = ARGON2I

password_query = SELECT username AS user,password FROM mailbox WHERE username = '%u' AND active='1'

user_query = SELECT maildir, 2000 AS uid, 2000 AS gid FROM mailbox WHERE username = '%u' AND active='1'

iterate_query = SELECT username AS user FROM mailbox

Restart Dovecot.

sudo systemctl restart dovecot

When a user tries to log in, Dovecot would use the Argon2 algorithm to generate a password hash from the password entered by the user, then compare it with the password hash stored in the database. If they match, then the user can log in successfully.

Step 13: Add Domain and Mailboxes in PostfixAdmin

Log in to PostfixAdmin web interface as the admin. Click the Domain List tab and select New Domain to add a domain. You can choose how many aliases and mailboxes are allowed for this domain.

debian postfixadmin add domain

Then click Virtual List tab and select Add Mailbox to add a new email address for your domain.

debian postfixadmin Create a new mailbox

Next, you can open your desktop email client such as Mozilla Thunderbird and add a mail account.

  • In the incoming server section, select IMAP protocol, enter mail.your-domain.com as the server name, choose port 143 and STARTTLS. Choose normal password as the authentication method.
  • In the outgoing section, select SMTP protocol, enter mail.your-domain.com as the server name, choose port 587 and STARTTLS. Choose normal password as the authentication method.

thunderbird-mail-client-configuration

Hint: You can also use port 993 with SSL/TLS encryption for IMAP, and use port 465 with SSL/TLS encryption for SMTP. You should not use port 25 as the SMTP port in mail clients to submit outgoing emails.

You should now be able to connect to your own email server and also send and receive emails with your desktop email client! Note that you cannot use local Unix accounts to login now. You must log in with the virtual user created from PostfixAdmin web interface.

Troubleshooting Tips

As a rule of thumb, you should always check the mail log (/var/log/mail.log) on your mail server when an error happens. The following is a list of specific errors and troubleshooting tips.

Can’t login from Mail Clients

If you can’t log into your mail server from a desktop mail client, scan your mail server to find if the ports are open. Note that you should run the following command from another Linux computer or server. If you run it on your mail server, then the ports will always appear to be open.

sudo nmap mail.your-domain.com

And check if Dovecot is running.

systemctl status dovecot

You can also check the mail log (/var/log/mail.log), which may give you some clues. If Dovecot fails to start, the error might not be logged to the /var/log/mail.log file, you can run the following command to see what’s wrong.

sudo journalctl -eu dovecot

If you see the following error in the mail log, it’s likely that you didn’t set a correct password in the .cf files under /etc/postfix/sql/ directory.

postfix/trivial-rewrite[28494]: warning: virtual_alias_domains: proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_maps.cf: table lookup problem
postfix/trivial-rewrite[28494]: warning: virtual_alias_domains lookup failure

If you see the following error in the mail log, it’s because you forgot to add mail_location = maildir:~/Maildir in the /etc/dovecot/conf.d/10-mail.conf file.

open(/var/mail/[email protected]) failed: Permission denied (euid=2000(vmail) egid=2000(vmail) missing +w perm: /var/mail, we're not in group 8(mail), dir owned by 0:8 mode=0775

Cloudflare DNS

As I said in part 1, if you use Cloudflare DNS service, you should not enable the CDN (proxy) feature when creating DNS A record and AAAA record for the hostname of your mail server. Cloudflare doesn’t support SMTP or IMAP proxy.

Relay Access Denied

If you see the “relay access denied” error when trying to send emails from a mail client, it’s most likely that you use port 25 as the SMTP port in your mail client. As I said a while ago, you should use port 587 or 465 as the SMTP port in mail clients (Mozilla Thunberbird, Microsoft Outlook, etc) to submit outgoing emails. Port 25 should be used for SMTP server to SMTP server communications.

postfix dovecot relay access denied

iOS Mail App

If you use the iOS Mail app to log into your mail server and encounter the following error.

ios the mail server is not responding

You can try to fix it by enforcing SSL encryption, for both SMTP and IMAP.

ios mail enforce SSL encryption

Fun fact: It seems the iOS Mail app has difficulty in supporting STARTTLS on IMAP port 143, but it supports STARTTLS on the submission port 587.

Temporary Lookup Failure

If your mail server was working fine for some time, but suddenly you find the following error in the mail log,

Aug 25 20:25:24 mx postfix/trivial-rewrite[3313]: warning: virtual_alias_domains: proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_maps.cf: table lookup problem
Aug 25 20:25:24 mx postfix/trivial-rewrite[3313]: warning: virtual_alias_domains lookup failure
Aug 25 20:25:24 mx postfix/submission/smtpd[3464]: NOQUEUE: reject: 451 4.3.0 <[email protected]>: Temporary lookup failure;  proto=ESMTP
Aug 25 20:25:24 mx postfix/submission/smtpd[3464]: Temporary lookup failure

It’s likely that your MariaDB/MySQL database stopped somehow. You can use the following command to check when your database server stopped.

sudo journalctl -eu mariadb

or

sudo journalctl -eu mysql

A common cause for this situation is that your server is out-of-memory. Check if your server has enough memory.

htop

or

free -m

Automatically Clean the Junk Folder and Trash Folder

To delete emails in Junk folder for all users, you can run

sudo doveadm expunge -A mailbox Junk all

To delete emails in Trash folder, run

sudo doveadm expunge -A mailbox Trash all

I think it’s better to clean emails that have been in the Junk or Trash folder for more than 2 weeks, instead of cleaning all emails.

sudo doveadm expunge -A mailbox Junk savedbefore 2w

Then add a cron job to automate the job.

sudo crontab -e

Add the following line to clean Junk and Trash folder every day.

@daily doveadm expunge -A mailbox Junk savedbefore 2w;doveadm expunge -A mailbox Trash savedbefore 2w

To receive report when a Cron job produces an error, you can add the following line above all Cron jobs.

MAILTO="[email protected]"

Save and close the file. And you’re done.

Change User Password in PostfixAdmin

Users can log into PostfixAdmin at https://postfixadmin.example.com/users/login.php, then change their passwords.

Restricting Access to Sendmail

By default, any local user can use the sendmail binary to submit outgoing emails. Now that your mail server is using virtual mailboxes, you might want to restrict access to the sendmail binary to trusted local users only, so a malicious user can’t use it to send a large volume of emails to damage your mail server’s reputation. Edit the Postfix main configuration file.

sudo nano /etc/postfix/main.cf

Add the following line to the end of this file, so only the root and www-data user can submit emails via sendmail. You can also add other usernames.

authorized_submit_users = root,www-data

Save and close the file. Then restart Postfix.

sudo systemctl restart postfix

How to Upgrade PostfixAdmin

Sometimes there might be bugs in the current PostfixAdmin that can be fixed by upgrading to a new version. It’s very simple to upgrade PostfixAdmin. When a new version of PostfixAdmin comes out, then you need to

  • Make a copy of the /var/www/postfixadmin/config.local.php file to your home directory.
  • Remove the PostfixAdmin web directory (sudo rm /var/www/postfixadmin/ -r)
  • Go through step 2, step 3, step 5, and step 10 again in this tutorial. When doing step 5, simply copy the config.local.php file from your home directory. In step 10, the PostfixAdmin database schema will be automatically updated when you visit the setup.php web page.

I once had a login loop problem in my PostfixAdmin installation and it’s fixed by upgrading PostfixAdmin to the latest version.

Next Step

I hope this tutorial helped you install and use PostfixAdmin on Debian to create virtual mailboxes. In part 4, I will show you how to set up SPF and DKIM with Postfix to improve email deliverability and in a future tutorial, I’m going to show you how to host multiple domains with PostfixAdmin.

If you want to access emails from a web browser, then I recommend Roundcube, which is a very popular and featured-rich open-source webmail client. As always, if you found this post useful, subscribe to our free newsletter to get more tips and tricks. Take care 🙂

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40 Responses to “Part 3: PostfixAdmin – Create Virtual Mailboxes on Debian 11/10 Mail Server

  • Do you consider PostfixAdmin a better alternative than ViMbAdmin?

    • Never heard it before. Looks like it’s a fork of PostfixAdmin. Looking at the ViMbAdmin screenshots, I don’t find any particular feature that convinces me to migrate to it.

  • Irasandi
    6 months ago

    When i test it by sending mail from [email protected] to my gmail address the sender name is john instead of John Doe, is there any way to fix this?

    • If you don’t set a name in your mail client (such as Thunderbird), then gmail will use your account username (john).

      To display your full name (John Doe), simply set a name in your mail client.

      • Irasandi
        6 months ago

        Thank you, it’s showing the full name now after setting name in outlook.

  • Csaba Bocskai
    3 months ago

    Hi

    For more than a week, I’m stuck at setting up Postfix Admin.
    Managed to create setup password but having issues with the following warnings and errors:

    Warnings

        ⚠ Database - PostgreSQL (pdo_pgsql) extension not found
        ⚠ Change the database_type to 'sqlite' in config.local.php if you want to use SQLite
    

    Errors (MUST be fixed)

        ⛔Password Hashing - attempted to use configured encrypt backend (dovecot:ARGON2I) triggered an error: /usr/bin/doveadm pw -r 5 failed, see error log for details
        ⛔You will have problems logging into PostfixAdmin.
        ⛔Check out our Dovecot documentation at https://github.com/postfixadmin/postfixadmin/blob/master/DOCUMENTS/DOVECOT.txt, specifically around '3. Permissions'.
    

    Can you, please, help me out?

    I did quite a lot of googling and tried suggested steps but nothing seems to work.

    • Maybe you need to run this command:

      sudo setfacl -R -m u:www-data:rx /etc/letsencrypt/live/ /etc/letsencrypt/archive/
      • Csaba Bocskai
        3 months ago

        Looks like somehow I missed to make that step.
        Now it works.
        Thank you!

  • If there some Maildirs in /home/~, how to move the content to the new VirtualMailboxes?

    • First, back up your current maildir directory.

      tar -cpvzf maildir.tar.gz /home/username/Maildir/

      Then sync the Maildir for the virtual user. For example,

      sudo rsync -av --progress /home/username/Maildir/ /var/vmail/example.com/user

      Next, change the ownership to vmail user.

      sudo chown vmail:vmail /var/vmail/example.com/user/ -R
    • Thank You!

  • Hi, I get the following error in photo attached. Thanks for any tip

    • found the solution by giving following permission:
      chown root:www-data /etc/letsencrypt/live/mail.example.com/privkey.pem

    • Or, use the following command.

      sudo setfacl -R -m u:www-data:rx /etc/letsencrypt/live/ /etc/letsencrypt/archive/
      • Flemming
        2 months ago

        Please take a look at this alternative installation of postfixadmin.

        $ sudo apt install git
        $ cd /var/www
        $ sudo git clone https://github.com/postfixadmin/postfixadmin.git
        $ cd /var/www/postfixadmin
        $ sudo -u bash install.sh
        $ sudo chown -R www-data. /var/www/postfixadmin
        

        It substitutes step 2 and 3. Perhaps except:

        setfacl -R -m u:www-data:rx /etc/letsencrypt/live/ /etc/letsencrypt/archive/
        

        (I had done that before I used the alternative installation of postfixadmin.) This alternative installation made all three errors disappear and made login possible.

        Xiao, thank you for your really, really good howto!!!

  • In this tutorial you reference using either Apache or NginX webservers for Postfixadmin. However, I have not found a tutorial by you that addresses setting up NginX. Since many of your tutorials assume some of your previous tutorials. Can you recommend a good NginX setup tutorial which will be compatible with your email tutorials?. Thanks…RDK

    • There’s no need to “set up Nginx” after installing Nginx. Simply copy the /etc/nginx/conf.d/postfixadmin.conf file and you are good to go.

      • Xiao….Well, I’m back to this project after a long delay. Regarding my question about “setting up NginX” you replied that “There’s no need to “set up Nginx” after installing Nginx. Simply copy the /etc/nginx/conf.d/postfixadmin.conf file and you are good to go.”

        I just looked at my Part 1 work and I’m not clear on which file to copy. I don’t find a postfixadmin.conf file in my current (before NginX install) setup. Can you clarify? Thanks….Rob

        • Xiao….OK, thanks. I’ve just stated Part 2 and have not gotten to that step in Part 3. Thanks for the clarification….Rob

    • I mean you should copy the content of /etc/nginx/conf.d/postfixadmin.conf in step 6 on this web page to your mail server.

  • Flemming
    2 months ago

    I could not make postfixadmin work. But, this installation of the php-stuff worked:
    sudo apt install git
    $ cd /var/www
    $ sudo git clone https://github.com/postfixadmin/postfixadmin.git
    $ cd /var/www/postfixadmin
    $ sudo -u bash install.sh
    $ sudo chown -R www-data. /var/www/postfixadmin

  • Flemming
    2 months ago

    I had a relay access denied problem. It disappeared when I changed mail.example.org to example.org everywhere on the server, and did the same in the mx record. I don’t why, but I guess dovecot expected login like this: [email protected] Just a suggestion about what could give problems.

    • You should always check the mail log file (/var/log/mail.log) and post it here so I can give you advice. Also enable debugging in /etc/dovecot/conf.d/10-auth.conf to find out what’s wrong.

      The entire mail server tutorial serious assumes you are using mail.example.org as the hostname. It you change it, you may have problem in later parts of this tutorial serious.

      • Flemming
        2 months ago

        First of all. Thank you very much for this splendid tutorial. It is really good because because it works!!! But, also because you explain why one should do as you recommend. It is also helpful that you show images of how the files should look after changes; this makes it easy to check whether one has made errors.
        But, now to my problem:
        I tried again to set the mail server up as you recommend calling it mail.example.org, and again I got access relay denied. So, I had to return to call the server example.org, and not mail.example.org; now it works again.

        hostname and mailname: mail.example.org
        MX:
        Domain: example.org
        MX exchanger: mail.example.org

        Setup in thunderbird: imap-server mail.example.org:143 login: [email protected]
        starttls
        smtp-server mail.example.org: 587
        Thunderbird asks me to accept an unauthorised certifikate on example.org:143 (not mail.example.org:143). It does so again and again, and nothing happens.

        From /etc/

        grep -RI example.org /etc
        /etc/resolv.conf:domain example.org
        /etc/resolv.conf:search example.org
        /etc/mailname:mail.example.org
        /etc/hosts:200.200.200.200 example.org
        /etc/apache2/sites-available/postfixadmin.conf:  ServerName postfixadmin.example.org
        /etc/apache2/sites-enabled/postfixadmin.conf:  ServerName postfixadmin.example.org
        /etc/postfix/main.cf:smtpd_tls_cert_file=/etc/letsencrypt/live/mail.example.org/fullchain.pem
        /etc/postfix/main.cf:smtpd_tls_key_file=/etc/letsencrypt/live/mail.example.org/privkey.pem
        /etc/postfix/main.cf:myhostname = mail.example.org
        /etc/hostname:mail.example.org
        /etc/letsencrypt/accounts/acme-v02.api.letsencrypt.org/directory/77cfd455857928bcfcd35b648932a284/meta.json:{"creation_dt": "2022-03-23T09:45:31Z", "creation_host": "example.org"}
        /etc/letsencrypt/renewal/mail.example.org.conf:archive_dir = /etc/letsencrypt/archive/mail.example.org
        /etc/letsencrypt/renewal/mail.example.org.conf:cert = /etc/letsencrypt/live/mail.example.org/cert.pem
        /etc/letsencrypt/renewal/mail.example.org.conf:privkey = /etc/letsencrypt/live/mail.example.org/privkey.pem
        /etc/letsencrypt/renewal/mail.example.org.conf:chain = /etc/letsencrypt/live/mail.example.org/chain.pem
        /etc/letsencrypt/renewal/mail.example.org.conf:fullchain = /etc/letsencrypt/live/mail.example.org/fullchain.pem
        

        From mail.log:

        tail -f /var/log/mail.log
        mail dovecot: auth: Debug: auth client connected (pid=1266609)
        Mar 23 14:25:09 mail dovecot: auth: Debug: auth client connected (pid=1266610)
        Mar 23 14:25:09 mail dovecot: imap-login: Disconnected (no auth attempts in 0 secs): user=, rip=192.168.1.1, lip=192.168.1.250, TLS handshaking: SSL_accept() failed: error:14094412:SSL routines:ssl3_read_bytes:sslv3 alert bad certificate: SSL alert number 42, session=
        Mar 23 14:25:09 mail dovecot: imap-login: Disconnected (no auth attempts in 0 secs): user=, rip=192.168.1.1, lip=192.168.1.250, TLS handshaking: SSL_accept() failed: error:14094412:SSL routines:ssl3_read_bytes:sslv3 alert bad certificate: SSL alert number 42, session=
        Mar 23 14:25:10 mail postfix/submission/smtpd[1265922]: connect from unknown[192.168.1.1]
        Mar 23 14:25:10 mail dovecot: auth: Debug: auth client connected (pid=1266611)
        Mar 23 14:25:10 mail dovecot: auth: Debug: client in: AUTH#0111#011PLAIN#011service=imap#011secured=tls#011session=xq+rqOLaeNPAqAEB#011lip=192.168.1.250#011rip=192.168.1.1#011lport=143#011rport=54136#011local_name=taenkom.dk#011resp=AHRvcmVAdGFlbmtvbS5kawBnYzUza2wwOQ== (previous base64 data may contain sensitive data)
        Mar 23 14:25:10 mail dovecot: auth: Debug: sql([email protected],192.168.1.1,): Performing passdb lookup
        Mar 23 14:25:10 mail postfix/submission/smtpd[1265922]: NOQUEUE: reject: RCPT from unknown[192.168.1.1]: 554 5.7.1 : Recipient address rejected: Access denied; from= to= proto=ESMTP helo=
        Mar 23 14:25:10 mail postfix/submission/smtpd[1265922]: disconnect from unknown[192.168.1.1] ehlo=2 starttls=1 mail=1 rcpt=0/1 rset=1 quit=1 commands=6/7
        Mar 23 14:25:10 mail dovecot: auth-worker(1266612): Debug: Loading modules from directory: /usr/lib/dovecot/modules/auth
        Mar 23 14:25:10 mail dovecot: auth-worker(1266612): Debug: Module loaded: /usr/lib/dovecot/modules/auth/lib20_auth_var_expand_crypt.so
        Mar 23 14:25:10 mail dovecot: auth-worker(1266612): Debug: Module loaded: /usr/lib/dovecot/modules/auth/libdriver_mysql.so
        Mar 23 14:25:10 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): Server accepted connection (fd=14)
        Mar 23 14:25:10 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): Sending version handshake
        Mar 23 14:25:10 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: Handling PASSV request
        Mar 23 14:25:10 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): Performing passdb lookup
        Mar 23 14:25:10 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): query: SELECT username AS user,password FROM mailbox WHERE username = '[email protected]' AND active='1'
        Mar 23 14:25:11 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): Finished passdb lookup
        Mar 23 14:25:11 mail dovecot: auth: Debug: sql([email protected],192.168.1.1,): Finished passdb lookup
        Mar 23 14:25:11 mail dovecot: auth: Debug: auth([email protected],192.168.1.1,): Auth request finished
        Mar 23 14:25:11 mail dovecot: auth: Debug: client passdb out: OK#0111#[email protected]#011
        Mar 23 14:25:11 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: Finished
        Mar 23 14:25:11 mail dovecot: auth: Debug: master in: REQUEST#0113285319681#0111266611#0111#01199e577a71bd6310fa14d9e9cd0a0e776#011session_pid=1266613#011request_auth_token
        Mar 23 14:25:11 mail dovecot: auth: Debug: sql([email protected],192.168.1.1,): Performing userdb lookup
        Mar 23 14:25:11 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: Handling USER request
        Mar 23 14:25:11 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): Performing userdb lookup
        Mar 23 14:25:11 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): SELECT maildir, 2000 AS uid, 2000 AS gid FROM mailbox WHERE username = '[email protected]' AND active='1'
        Mar 23 14:25:11 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): Finished userdb lookup
        Mar 23 14:25:11 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: Finished
        Mar 23 14:25:11 mail dovecot: auth: Debug: sql([email protected],192.168.1.1,): Finished userdb lookup
        Mar 23 14:25:11 mail dovecot: auth: Debug: master userdb out: USER#0113285319681#[email protected]#011maildir=taenkom.dk/tore/#011uid=2000#011gid=2000#011auth_mech=PLAIN#011auth_token=af766fb72552070b28bedd20ab17876ad20f0c0f
        Mar 23 14:25:11 mail dovecot: imap-login: Login: user=, method=PLAIN, rip=192.168.1.1, lip=192.168.1.250, mpid=1266613, TLS, session=
        Mar 23 14:26:03 mail dovecot: imap([email protected]): Connection closed (IDLE finished 36.747 secs ago) in=1033 out=10101 deleted=0 expunged=0 trashed=0 hdr_count=3 hdr_bytes=4268 body_count=0 body_bytes=0
        Mar 23 14:26:03 mail dovecot: imap([email protected]): Connection closed (IDLE finished 48.751 secs ago) in=322 out=1166 deleted=0 expunged=0 trashed=0 hdr_count=0 hdr_bytes=0 body_count=0 body_bytes=0
        Mar 23 14:26:08 mail postfix/submission/smtpd[1265922]: connect from unknown[192.168.1.1]
        Mar 23 14:26:08 mail dovecot: auth: Debug: auth client connected (pid=1266780)
        Mar 23 14:26:08 mail dovecot: auth: Debug: client in: AUTH#0111#011PLAIN#011service=imap#011secured=tls#011session=AFwhrOLaftPAqAEB#011lip=192.168.1.250#011rip=192.168.1.1#011lport=143#011rport=54142#011local_name=mail.taenkom.dk#011resp=AHRvcmVAdGFlbmtvbS5kawBnYzUza2wwOQ== (previous base64 data may contain sensitive data)
        Mar 23 14:26:08 mail dovecot: auth: Debug: sql([email protected],192.168.1.1,): Performing passdb lookup
        Mar 23 14:26:08 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: Handling PASSV request
        Mar 23 14:26:08 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): Performing passdb lookup
        Mar 23 14:26:08 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): query: SELECT username AS user,password FROM mailbox WHERE username = '[email protected]' AND active='1'
        Mar 23 14:26:08 mail postfix/submission/smtpd[1265922]: NOQUEUE: reject: RCPT from unknown[192.168.1.1]: 554 5.7.1 : Recipient address rejected: Access denied; from= to= proto=ESMTP helo=
        Mar 23 14:26:08 mail postfix/submission/smtpd[1265922]: disconnect from unknown[192.168.1.1] ehlo=2 starttls=1 mail=1 rcpt=0/1 rset=1 quit=1 commands=6/7
        Mar 23 14:26:09 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): Finished passdb lookup
        Mar 23 14:26:09 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: Finished
        Mar 23 14:26:09 mail dovecot: auth: Debug: sql([email protected],192.168.1.1,): Finished passdb lookup
        Mar 23 14:26:09 mail dovecot: auth: Debug: auth([email protected],192.168.1.1,): Auth request finished
        Mar 23 14:26:09 mail dovecot: auth: Debug: client passdb out: OK#0111#[email protected]#011
        Mar 23 14:26:09 mail dovecot: auth: Debug: master in: REQUEST#0113960209409#0111266780#0111#011bf31f73f28c4e20fa076fccaa38c8c9a#011session_pid=1266794#011request_auth_token
        Mar 23 14:26:09 mail dovecot: auth: Debug: sql([email protected],192.168.1.1,): Performing userdb lookup
        Mar 23 14:26:09 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: Handling USER request
        Mar 23 14:26:09 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): Performing userdb lookup
        Mar 23 14:26:09 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): SELECT maildir, 2000 AS uid, 2000 AS gid FROM mailbox WHERE username = '[email protected]' AND active='1'
        Mar 23 14:26:09 mail dovecot: auth: Debug: sql([email protected],192.168.1.1,): Finished userdb lookup
        Mar 23 14:26:09 mail dovecot: auth: Debug: master userdb out: USER#0113960209409#[email protected]#011maildir=taenkom.dk/tore/#011uid=2000#011gid=2000#011auth_mech=PLAIN#011auth_token=4ca079eef8b84fe7159a5354a7c95a2647cb0d90
        Mar 23 14:26:09 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: sql([email protected],192.168.1.1,): Finished userdb lookup
        Mar 23 14:26:09 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): auth-worker: Finished
        Mar 23 14:26:09 mail dovecot: imap-login: Login: user=, method=PLAIN, rip=192.168.1.1, lip=192.168.1.250, mpid=1266794, TLS, session=
        Mar 23 14:26:36 mail postfix/submission/smtpd[1265922]: connect from unknown[192.168.1.1]
        Mar 23 14:26:36 mail postfix/submission/smtpd[1265922]: NOQUEUE: reject: RCPT from unknown[192.168.1.1]: 554 5.7.1 : Recipient address rejected: Access denied; from= to= proto=ESMTP helo=
        Mar 23 14:26:36 mail postfix/submission/smtpd[1265922]: lost connection after RCPT from unknown[192.168.1.1]
        Mar 23 14:26:36 mail postfix/submission/smtpd[1265922]: disconnect from unknown[192.168.1.1] ehlo=2 starttls=1 mail=1 rcpt=0/1 rset=1 commands=5/6
        Mar 23 14:26:55 mail postfix/smtpd[1266913]: connect from unknown[2.56.56.158]
        Mar 23 14:26:55 mail postfix/smtpd[1266913]: lost connection after AUTH from unknown[2.56.56.158]
        Mar 23 14:26:55 mail postfix/smtpd[1266913]: disconnect from unknown[2.56.56.158] ehlo=1 auth=0/1 commands=1/2
        Mar 23 14:27:09 mail dovecot: auth-worker(1266612): Debug: conn unix:auth-worker (pid=1265336,uid=113): Disconnected: Connection closed (fd=-1)
        
    • In /etc/dovecot/conf.d/10-ssl.conf, make sure you have the following lines:

      ssl_cert = </etc/letsencrypt/live/mail.example.com/fullchain.pem
      ssl_key = </etc/letsencrypt/live/mail.example.com/privkey.pem
      

      Because you have TLS certificate for mail.example.com, instead of example.com.

      Also, in /etc/postfix/main.cf, the TLS configuration should be:

      smtpd_tls_cert_file=/etc/letsencrypt/live/mail.example.com/fullchain.pem
      smtpd_tls_key_file=/etc/letsencrypt/live/mail.example.com/privkey.pem
      

      Then, restart Postfix and Dovecot.

      sudo systemctl restart postfix dovecot
  • I set it up online according to the tutorial, but I encountered problems in using it. I added my domain name, but I can’t see anything in the domain name list. If I add the domain name again, it will show that adding the domain name failed. What should I do?There are some things below.

    • like this.In fact, I have added the domain name, but there is nothing displayed。Thank you.I did quite a lot of googling and tried suggested steps but nothing seems to work.Could you please help me?

    • Once you add a domain name, you need to add email addresses for this domain name.

    • I can’t guarantee it will work if you don’t add the domain from the web interface.

      I never tried to add a domain name using MySQL/MariaDB console commands.

      • I added domain from the web interface, not using PGSQL console commands. I mean, if I add a domain name like this, it will be displayed in my database, but I can’t see the list of domain names in my web interface. How should I add an e-mail address after adding a domain name? I don’t see the option of adding an e-mail address.

  • If you’re talking about add mailbox, I did. However, due to unknown reasons, the domain I added cannot be displayed. Although I saw the domain I added in the database, I was unable to select a domain name for it. I think there may be a problem that caused postfix to not read the domain in my database.

  • 你好,非常感谢你之前对我的帮助。虽然我没有找到具体原因,但是我卸载了php7.0并安装了php7.4,它可以进行正常的工作了。我是用postfixadmin新建了域和邮箱,并使用我的QQ邮箱向它发送邮件在我的/home/mail下可以收到邮件,但它似乎又出了问题,我不能发送邮件。如果我用postfixadmin web界面发送邮件,在我的/var/log/maillog显示
    Mar 28 17:43:27 mail postfix/smtpd[21091]: connect from VM-0-2-centos[::1]
    Mar 28 17:43:27 mail postfix/smtpd[21091]: NOQUEUE: reject: RCPT from VM-0-2-centos[::1]: 454 4.7.1 : Relay access denied; from= to= proto=ESMTP helo=
    Mar 28 17:43:27 mail postfix/smtpd[21091]: warning: non-SMTP command from VM-0-2-centos[::1]: To: [email protected]
    Mar 28 17:43:27 mail postfix/smtpd[21091]: disconnect from VM-0-2-centos[::1]
    如果我尝试用foxmail登录,它会显示
    Mar 28 17:50:07 mail postfix/smtpd[22328]: warning: unknown[14.120.115.228]: SASL LOGIN authentication failed: Connection lost to authentication server
    Mar 28 17:50:17 mail postfix/smtpd[22328]: warning: unknown[14.120.115.228]: SASL PLAIN authentication failed: Connection lost to authentication server
    Mar 28 17:50:17 mail postfix/smtpd[22328]: lost connection after AUTH from unknown[14.120.115.228]
    Mar 28 17:50:17 mail postfix/smtpd[22328]: disconnect from unknown[14.120.115.228]
    [[email protected] DOCUMENTS]# tail /var/log/maillog
    Mar 28 17:43:27 mail postfix/smtpd[21091]: warning: non-SMTP command from VM-0-2-centos[::1]: To: [email protected]
    Mar 28 17:43:27 mail postfix/smtpd[21091]: disconnect from VM-0-2-centos[::1]
    Mar 28 17:46:47 mail postfix/anvil[21093]: statistics: max connection rate 1/60s for (smtp:::1) at Mar 28 17:43:27
    Mar 28 17:46:47 mail postfix/anvil[21093]: statistics: max connection count 1 for (smtp:::1) at Mar 28 17:43:27
    Mar 28 17:46:47 mail postfix/anvil[21093]: statistics: max cache size 1 at Mar 28 17:43:27
    Mar 28 17:49:56 mail postfix/smtpd[22328]: connect from unknown[14.120.115.228]
    Mar 28 17:50:07 mail postfix/smtpd[22328]: warning: unknown[14.120.115.228]: SASL LOGIN authentication failed: Connection lost to authentication server
    Mar 28 17:50:17 mail postfix/smtpd[22328]: warning: unknown[14.120.115.228]: SASL PLAIN authentication failed: Connection lost to authentication server
    Mar 28 17:50:17 mail postfix/smtpd[22328]: lost connection after AUTH from unknown[14.120.115.228]
    Mar 28 17:50:17 mail postfix/smtpd[22328]: disconnect from unknown[14.120.115.228]
    似乎是身份验证出现了问题,我是按照官方postfixadmin的教程设置postfix和dovecot的,因为我使用的数据库和你的不一样。
    我运行systemctl status dovecot 得到一条错误信息Can’t open PID file /var/run/dovecot/master.pid (yet?) after start: No such file or directory,但是查看/var/run/dovecot目录下面存在这个文件,我试着停止dovecot进程并删除这个文件再重启dovecot,但是没有效果。我在谷歌上搜索了很多,但是也没有找到解决办法。非常感谢你的帮助!
    这是我的postfix的main.cf
    queue_directory = /var/spool/postfix
    command_directory = /usr/sbin
    daemon_directory = /usr/libexec/postfix
    data_directory = /var/lib/postfix
    mail_owner = postfix
    myhostname = smtp.bnrevive.com
    mydomain = bnrevive.com
    myorigin = $mydomain
    inet_interfaces = all
    inet_protocols = all
    unknown_local_recipient_reject_code = 550
    mynetworks = 0.0.0.0/0
    alias_maps = hash:/etc/aliases
    alias_database = hash:/etc/aliases
    home_mailbox = Maildir/

    debug_peer_level = 2
    debugger_command =
    PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
    ddd $daemon_directory/$process_name $process_id & sleep 5
    sendmail_path = /usr/sbin/sendmail.postfix
    newaliases_path = /usr/bin/newaliases.postfix
    mailq_path = /usr/bin/mailq.postfix
    setgid_group = postdrop
    html_directory = no
    manpage_directory = /usr/share/man
    sample_directory = /usr/share/doc/postfix-2.10.1/samples
    readme_directory = /usr/share/doc/postfix-2.10.1/README_FILES
    virtual_uid_maps = static:200
    virtual_gid_maps = static:12
    smtpd_sasl_type = dovecot
    smtpd_sasl_path = private/auth
    smtpd_sasl_authenticated_header = yes
    smtpd_sasl_auth_enable = yes
    smtpd_sasl_security_options = noanonymous
    broken_sasl_auth_clients = yes
    smtpd_relay_restrictions = permit_mynetworks,permit_sasl_authenticated,defer_unauth_destination
    virtual_alias_maps = pgsql:/etc/postfix/pgsql/virtual_alias_maps.cf
    virtual_mailbox_domains = pgsql:/etc/postfix/pgsql/virtual_domains_maps.cf
    virtual_mailbox_maps = pgsql:/etc/postfix/pgsql/virtual_mailbox_maps.cf
    virtual_mailbox_base = /home/mail
    relay_domains = $mydestination, proxy:pgsql:/etc/postfix/pgsql/relay_domains.cf
    virtual_mailbox_limit = 512000000
    virtual_minimum_uid = 8
    virtual_transport = virtual
    local_transport = virtual
    local_recipient_maps = $virtual_mailbox_maps
    这是我的master.cf
    smtp inet n – n – – smtpd
    submission inet n – n – – smtpd
    -o syslog_name=postfix/submission
    -o smtpd_tls_security_level=encrypt
    -o smtpd_sasl_auth_enable=yes
    -o smtpd_sasl_type=dovecot
    -o smtpd_sasl_path=private/auth
    -o smtpd_tls_wrappermode=no
    -o mynetworks=127.0.0.0/8
    -o smtpd_relay_restrictions=permit_mynetworks,permit_sasl_authenticated,defer_unauth_destination
    -o milter_macro_daemon_name=ORIGINATING
    pickup unix n – n 60 1 pickup
    cleanup unix n – n – 0 cleanup
    qmgr unix n – n 300 1 qmgr
    tlsmgr unix – – n 1000? 1 tlsmgr
    rewrite unix – – n – – trivial-rewrite
    bounce unix – – n – 0 bounce
    defer unix – – n – 0 bounce
    trace unix – – n – 0 bounce
    verify unix – – n – 1 verify
    flush unix n – n 1000? 0 flush
    proxymap unix – – n – – proxymap
    proxywrite unix – – n – 1 proxymap
    smtp unix – – n – – smtp
    relay unix – – n – – smtp
    showq unix n – n – – showq
    error unix – – n – – error
    retry unix – – n – – error
    discard unix – – n – – discard
    local unix – n n – – local
    virtual unix – n n – – virtual
    lmtp unix – – n – – lmtp
    anvil unix – – n – 1 anvil
    scache unix – – n – 1 scache

    dovecot unix – n n – – pipe
    flags=DRhu user=mailreader:mailreader argv=/usr/libexec/dovecot/deliver -f ${sender} -d ${recipient}
    这是我的dovecot.conf
    dict {
    #quota = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext
    #expire = sqlite:/etc/dovecot/dovecot-dict-sql.conf.ext
    }
    !include conf.d/*.conf
    auth_verbose = yes
    auth_debug = yes
    auth_debug_passwords = yes
    mail_location = maildir:/var/mail/vmail/%u/
    protocols = imap pop3
    login_greeting = Dovecot ready.
    ssl = yes
    ssl_cert = </etc/postfix/certs/www.bnrevive.com_bundle.pem
    ssl_key = </etc/postfix/certs/www.bnrevive.com.key
    userdb {
    driver = sql
    args = /etc/dovecot/dovecot-sql.conf
    }
    passdb {
    driver = sql
    args = /etc/dovecot/dovecot-sql.conf
    }
    first_valid_uid = 200
    login_greeting = My Mail Server
    disable_plaintext_auth = yes
    auth_mechanisms = plain login
    mail_plugins = $mail_plugins zlib
    namespace inbox {
    type = private
    inbox = yes
    location =
    mailbox Drafts {
    special_use = \Drafts
    }
    mailbox Junk {
    special_use = \Junk
    }
    mailbox Sent {
    special_use = \Sent
    }
    mailbox "Sent Messages" {
    special_use = \Sent
    }
    mailbox Trash {
    special_use = \Trash
    }
    prefix =
    }
    service auth {
    unix_listener /var/spool/postfix/private/auth {
    mode = 0666
    user = postfix
    group = postfix
    }
    user = postfix
    group = postfix
    }
    service imap {
    executable = imap
    }
    plugin {
    zlib_save_level = 6
    zlib_save = gz
    }
    protocol imap {
    mail_plugins = $mail_plugins imap_zlib
    }
    mail_max_userip_connections = 50
    log_path = /var/log/dovecot.log

    • If you didn’t follow my tutorial, then I can’t help you. I don’t want to fix other people’s problems when they don’t follow my advice.

      But I can tell you that your configuration is ridiculous.

      mynetworks = 0.0.0.0/0

      You are making the whole Internet as your own network.

  • I successfully set up PostfixAdmin and it seems to work except for catch-all aliases. I traced the issue down to what appears to be a defective query in /etc/postfix/sql/mysql_virtual_alias_domain_catchall_maps.cf. I apparently can’t post the query text without triggering a “hacking blocker.”

    Reading this, one can see it is attempting to join the alias and alias_domain tables with a condition that never matches, leading to empty results for any catchall alias. Further, it *requires* the existence of an alias_domain, so setting a catchall for a single domain (

    [email protected] => [email protected]

    ) cannot work). It is possible to make it work across domains (

    [email protected] => [email protected]

    ) by altering the query (changing join field), but that is obviously undesirable. It could probably also be made to work in both cases by more extensive alteration (left join + OR condition), but that seems ridiculous.

    I realize you didn’t write this query (it is nearly 15 years old, according to the source), but have you tested it? Am I possibly misunderstanding something?

    This tutorial series has been useful and I’m grateful for it. But it would be even more helpful if you could document your sources more thoroughly.

    thank you.

    • To create a catch-all in Postfixadmin, use * as alias.

      *@example.com    =>      [email protected]

      how to create catch all email address in Postfixadmin

      The SQL query in /etc/postfix/sql/mysql_virtual_alias_domain_catchall_maps.cf file is correct. To test, You can send an email to a random address on my domain like [email protected]

      • I did exactly like that. But keep getting “Recipient address rejected: User unknown in virtual mailbox table” in the log when sending to the alias.

      • If this works for you I am curious what your alias_domain table contains? Because any of those virtual_alias queries will return an empty result and thus fail when that table is empty. Joining (non-LEFT) to an empty table always returns an empty result.

        I found that I could make the single-domain catchall work by manually inserting into alias_domain a record having the same domain for *both* alias_domain and target_domain. But I saw no way to do this from the web UI and it really shouldn’t be necessary in the first place.

    • My alias_domain table is empty.
      postfixadmin create alias

      When you create a catchall alias, the record is stored in the alias table.
      postfixadmin create catchall alias
      The above screenshot shows that a catchall alias is created for linuxbabe.com. Emails coming for nonexistent addresses for linuxbabe.com will be sent to the [email protected] address.

      The SQL query in the mysql_virtual_alias_domain_catchall_maps.cf file is only used for alias domains.
      For example, when you create an alias domain

      domain1.tld          =>        domain2.tld

      Any emails coming for domain1.tld will be sent to the corresponding address on domain2.tld.

      [email protected]           =>     [email protected]
      [email protected]           =>      [email protected]
      

      If the target domain (domain2.tld) doesn’t have an email address ([email protected]), then emails coming for [email protected] will be rejected because Postfix can’t find this address on the target domain.

      But if you create a catchall alias on the target domain

      @domain2.tld           =>      [email protected]

      Then emails coming for [email protected] will be sent to [email protected] This is when the SQL query in the mysql_virtual_alias_domain_catchall_maps.cf file does the work.

      The /etc/postfix/main.cf file contains the following configuration.

      virtual_mailbox_domains = proxy:mysql:/etc/postfix/sql/mysql_virtual_domains_maps.cf
      virtual_mailbox_maps =
         proxy:mysql:/etc/postfix/sql/mysql_virtual_mailbox_maps.cf,
         proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_mailbox_maps.cf
      virtual_alias_maps =
         proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_maps.cf,
         proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_maps.cf,
         proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_catchall_maps.cf
      

      When Postfix tries to find an alias from the database, it uses SQL queries in the specified order. If it successfully found the alias using the SQL query in the mysql_virtual_alias_maps.cf file, it won’t use other SQL queries.

      • AARGH! I finally found the problem. I had copied the wrong query into one of the files. Sorry for wasting your time but thanks for helping me figure it out.

  • Simon Thémiot
    3 weeks ago

    Hello,
    At beginning : thanks a lot for your tutorial !

    So, sorry to disturb you but I’m little confusing cause I would like to use my actual configuration that I did with postfix and dovecot but it’s not actually with postfixadmin that is not really practical to manage users.
    So my databases tables right now is :

    +-----------------+
    | virtual_aliases |
    | virtual_domains |
    | virtual_users   |
    +-----------------+
    

    My postfix config with Mariadb in main.cf is :

    virtual_mailbox_domains = mysql:/etc/postfix/mysql-virtual-mailbox-domains.cf
    virtual_mailbox_maps = mysql:/etc/postfix/mysql-virtual-mailbox-maps.cf
    virtual_alias_maps = mysql:/etc/postfix/mysql-virtual-alias-maps.cf,
            mysql:/etc/postfix/mysql-virtual-email2email.cf
    

    My mysql-virtual-alias-maps.cf :

    user = **USER**
    password = **PASS**
    hosts = 127.0.0.1
    dbname = **DBName**
    query = SELECT destination FROM virtual_aliases WHERE source='%s'
    

    My mysql-virtual-email2email.cf :

    user = **USER**
    password = **PASS**
    hosts = 127.0.0.1
    dbname = **DBName**
    query = SELECT email FROM virtual_users WHERE email='%s'
    

    My mysql-virtual-mailbox-domains.cf :

    user = **USER**
    password = **PASS**
    hosts = 127.0.0.1
    dbname = **DBName**
    query = SELECT 1 FROM virtual_domains WHERE name='%s'
    

    My mysql-virtual-mailbox-maps.cf :

    user = **USER**
    password = **PASS**
    hosts = 127.0.0.1
    dbname = **DBName**
    query = SELECT 1 FROM virtual_users WHERE email='%s'
    

    So my question is : how could I “mix” the actual database with the postfixadmin database to retreive my actuals users / domains / alias in the postfixadmin’s database ? (which is which ? in fact ..) cause when I append this, nothing appear on postfixadmin web UI (cause it’s not the good structure indeed)
    Is it possible or it is better to do again all the config and lost all my actuals emails .. ?

    Thanks by advance for your time and your answer (and so sorry for my bad english language ..)

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