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Mailman3 Core Docker Image

When you spawn off this container, you must mount /opt/mailman to the container. Mailman's var directory will also be stored here so that it can persist across different sessions and containers. Any configuration at /opt/mailman/core/mailman-extra.cfg (on the host) will be added to the mailman's default generated confifguration (see below).

It is not advised to run multiple mailman processes on the same host sharing the same /opt/mailman (/opt/mailman/core on the host) directory as this will almost certainly be dangerous.


These are the variables that you MUST change before deploying:

  • HYPERKITTY_API_KEY: Hyperkitty's API Key, should be set to the same value as set for the mailman-core.

  • DATABASE_URL: URL of the type driver://user:password@hostname:port/databasename for the django to use. If not set, the default is set to sqlite:///opt/mailman-web-data/mailmanweb.db. The standard docker-compose.yaml comes with it set to a postgres database. It is not must to change this if you are happy with PostgreSQL.

  • DATABASE_TYPE: Its value can be one of sqlite, postgres or mysql as these are the only three database types that Mailman 3 supports. Its default value is set to sqlite along with the default database class and default database url above.

  • DATABASE_CLASS: Default value is mailman.database.sqlite.SQLiteDatabase. The values for this can be found in the mailman's documentation [here][11].

These are the variables that you don't need to change if you are using a standard version of docker-compose.yaml from this repository.

  • MM_HOSTNAME: Which hostname or IP should Core bind to for REST API and LMTP. If not defined output from the hostname -i command is used.

  • MAILMAN_REST_PORT: Which port should Core use for the REST API. If not defined the default is 8001.

  • MAILMAN_REST_USER: Which username should Core use for the REST API. If not defined the default is restadmin.

  • MAILMAN_REST_PASSWORD: Which password should Core use for the REST API. If not defined the default is restpass.

  • MTA: Mail Transfer Agent to use. Either exim or postfix. Default value is exim.

  • SMTP_HOST: IP Address/hostname from which you will be sending emails. Default value is the container's gateway retrieved from: /sbin/ip route | awk '/default/ { print $3 }'

  • SMTP_PORT: Port used for SMTP. Default is 25.

  • HYPERKITTY_URL: Default value is http://mailman-web:8000/hyperkitty

In case of a need for fine tuning of REST API web-server that uses Gunicorn (e.g. for raising of timeouts) /opt/mailman/core/gunicorn-extra.cfg file could be provided holding necessary configuration options.

Configuration file, shipped with Mailman Core, is used by default.

For example, to increase the default 30 sec timeout, which won't work for some API calls to highly populated lists, provide the following gunicorn-extra.cfg file:

graceful_timeout = 30
timeout = 300

Running Mailman-Core

It is highly recomended that you run this image along with the docker-compose.yaml file provided at the github repo of this image. However, it is possible to run this image as a standalone container if you want just a mailman-core.

$ mkdir -p /opt/mailman/core
$ docker run -it -e "HYPERKITTY_API_KEY=changeme" -h mailman-core -v /opt/mailman/core:/opt/mailman mailman-core

However, if you don't provide the environment DATABASE_URL, the database may not be persisted. All the configuration options are explained in more detail.

If you need mode advanced configuration for mailman, you can create /opt/mailman/mailman.cfg and it be added to the configuration inside the container. Note that anything inside this configuration will override the settings provided via the environment variables and their default values.

By default, the following settings are generated:

# mailman.cfg
incoming: mailman.mta.exim4.LMTP
outgoing: mailman.mta.deliver.deliver
lmtp_host: $MM_HOSTNAME
lmtp_port: 8024
smtp_host: $SMTP_HOST
smtp_port: $SMTP_PORT
configuration: python:mailman.config.exim4

sleep_time: 10s

hostname: $MM_HOSTNAME
admin_user: $MAILMAN_REST_USER
configuration: /etc/gunicorn.cfg

class: mailman_hyperkitty.Archiver
enable: yes
configuration: /etc/mailman-hyperkitty.cfg

# mailman-hyperkitty.cfg


You can use Postfix or Exim with this image to send emails. Mailman Core can interact with any modern MTA which can deliver emails over LMTP. The documentation for Mailman Core has configuration settigs for using them.

Only Exim and Postfix have been tested with these images and are supported as of now. There might be some limitations with using other MTAs in a containerized environments. Contributions are welcome for anything additional needed to support other MTAs.

To setup Exim or Posfix, checkout the documentation.