Mailman
Mailman is a mailing list management system. It is used in conjunction with a mail server.
Installation
Mailman can be used in conjunction with Postorius (for configuration) and Hyperkitty (for archiving).
mailman
user, therefore any calls to the mailman
executable have to be done as the mailman
user.Configuration
All configuration for Mailman takes place in /etc/mailman.cfg
. The schema explaining all possible configuration options and setting the defaults is stored in /usr/lib/python3.8/site-packages/mailman/config/schema.cfg
.
The configuration is also accessible via the command line. Run the following command as the mailman
user (e.g. using sudo or su):
[mailman]$ mailman conf
Database
Mailman by default uses an SQLite database in /var/lib/mailman/data/
, but can be configured to use MariaDB or PostgreSQL.
SQLite
The default location for the SQLite database is already reflected in the schema.cfg
and therefore does not have to be set in Mailman's configuration.
/etc/mailman.cfg
[database] url: sqlite:////var/lib/mailman/data/mailman.db
MariaDB
Install the python-pymysql package and configure a database on MariaDB.
/etc/mailman.cfg
[database] class: mailman.database.mysql.MySQLDatabase url: mysql+pymysql://myuser:mypassword@mymysqlhost/mailman?charset=utf8&use_unicode=1
PostgreSQL
Install the python-psycopg2 package and create a database using PostgreSQL.
/etc/mailman.cfg
[database] class: mailman.database.postgresql.PostgreSQLDatabase url: postgres://myuser:mypassword@mypghost/mailman
REST API
Mailman exposes its REST API based on the settings in the [webservice]
section of the configuration. Make sure to replace the default values for admin_user
and admin_pass
(do not use the example values below).
/etc/mailman.cfg
[webservice] admin_user: my_new_admin_user_name admin_pass: my_new_admin_user_password
ARC
By default DMARC and DKIM are disabled. The configuration takes place in the [ARC]
section of the configuration file. Make sure to set necessary values and read the documentation about the defaults.
/etc/mailman.cfg
[ARC] enabled: yes authserv_id: mailserver.tld trusted_authserv_ids: subdomain.mailserver.tld, other.mailserver.tld privkey: /path/to/privatekey.pem selector: test domain: mailserver.tld
MTA
To connect a mail-transfer-agent (MTA), it is necessary to configure the [mta]
section in the configuration file. Upstream documentation covers examples for postfix, exim and sendmail, but other MTAs are technically possible.
Postfix
To connect to a local postfix instance the following configuration section can be used:
/etc/mailman.cfg
[mta] incoming: mailman.mta.postfix.LMTP outgoing: mailman.mta.deliver.deliver lmtp_host: mail.example.com lmtp_port: 8024 smtp_host: mail.example.com smtp_port: 25
The postfix configuration has to be extended to ensure compatibility (see upstream notes).
/etc/postfix/main.cf
[..] recipient_delimiter = + unknown_local_recipient_reject_code = 550 owner_request_special = no [..]
Additionally, postfix needs to be made aware of mailman's transport maps. Depending on the postfix configuration these may look similar to the following.
transport_maps
, local_recipient_maps
, relay_domains
, virtual_mailbox_domains
and virtual_alias_maps
are merged with the additional values./etc/postfix/main.cf
[..] transport_maps = hash:/var/lib/mailman/data/postfix_lmtp local_recipient_maps = hash:/var/lib/mailman/data/postfix_lmtp relay_domains = hash:/var/lib/mailman/data/postfix_domains [..]
If postmap
is not directly accessible by mailman for creating the default hash-based alias maps, it is possible to generate regular expression based alias maps instead.
To overwrite the default Python-class based configuration, mailman allows the use of a configuration file. Create the following file:
/etc/postfix-mailman.cfg
[postfix] postmap_command: /usr/bin/postmap transport_file_type: regex
Add the file to the [mta]
section in mailman's configuration file.
/etc/mailman.cfg
[mta] [..] configuration: /etc/postfix-mailman.cfg
Afterwards the regexp
based exports can then be used in the postfix configuration.
/etc/postfix/main.cf
[..] transport_maps = regexp:/var/lib/mailman/data/postfix_lmtp local_recipient_maps = regexp:/var/lib/mailman/data/postfix_lmtp relay_domains = regexp:/var/lib/mailman/data/postfix_domains [..]
hash
to regexp
): [mailman]$ mailman aliases
To connect to a local postfix instance with a virtual mail setup, first set an alias domain. Afterwards alter the respective configuration.
/etc/postfix/main.cf
[..] local_recipient_maps = regexp:/var/lib/mailman/data/postfix_lmtp transport_maps = regexp:/var/lib/mailman/data/postfix_lmtp virtual_mailbox_domains = regexp:/var/lib/mailman/data/postfix_domains virtual_alias_maps = regexp:/var/lib/mailman/data/postfix_vmap [..]
Running
Enable and start mailman3.service
.
Several systemd services with timers exist, taking care of various aspects of the list management:
mailman3-digests.timer
: for sending out daily digests to subscribersmailman3-gatenews.timer
: for hourly polling of NNTP servers for newsmailman3-notify.timer
: for sending out daily notifications to admins about pending requests
Setup
Integrate with a mail server
Integrate with Hyperkitty
Mailman does not automatically archive mails on its own. The Hyperkitty web application is used for this purpose. Based on a plugin, mailman is able to send mails to a Hyperkitty instance for archival.
Install the mailman3-hyperkitty package and configure /etc/mailman-hyperkitty.cfg
.
/etc/mailman-hyperkitty.cfg
[general] base_url: https://example.tld/hyperkitty/ api_key: super_secret_password
Afterwards, make mailman aware of the plugin:
/etc/mailman.cfg
[archiver.hyperkitty] class: mailman_hyperkitty.Archiver enable: yes configuration: /etc/mailman-hyperkitty.cfg
Tips and tricks
Migrate from mailman < 3.0
Mailman offers the possibility of importing mailman < 3.0 based list databases (config.pck
). Run the following command as the mailman
user (e.g. using sudo or su):
[mailman]$ mailman import21 LISTSPEC PICKLE_FILE
Here, LISTSPEC
represents a fully-qualified name of a list to import (e.g. list@example.com
) and PICKLE_FILE
the path to the list's config.pck
file.
REST API
Mailman exposes a REST API, which can be interfaced using custom tooling, based on python-mailmanclient.
See also
- Mailman Documentation - The upstream documentation
- Mailmanclient Documentation - The upstream documentation
- Connecting to Mailman - The upstream documentation on mailman3-hyperkitty
- Mailman Suite Documentation - The (high level) upstream documentation for the entire Mailman Suite (Mailman, Hyperkitty and Postorius)