Mailing Lists

Mailman is installed on to run OpenStack related mailing lists, as well as host list archives.

At a Glance


Adding a List

A list may be added by adding it to the openstack-infra/system-config repository in system-config: inventory/service/host_vars/ For example:

- name: Example list
  description: 'This is an example'
  admin: ''
  password: "{{ mailman_list_password }}"

Scripted Changes to Lists

This may only be performed with root access to the list server.

Mailman supports running a python code snippet in the context of individual lists or every list on the system. The following example adds an address to the list of banned addresses for every list. This has proved useful in the case of attackers abusing the HTTP subscription interface to subscribe a target’s address to multiple mailing lists.

Banning an Address from All Lists

Create the file /usr/lib/mailman/bin/ with the following content:

def ban(m, address):
        if address not in m.ban_list:

And then run the withlist script as:

sudo -u list /usr/lib/mailman/bin/withlist -a -r ban "<address to ban>"

Because the script itself handles locking, do not use the -l argument to withlist. To run the same script on a single list, use:

sudo -u list /usr/lib/mailman/bin/withlist -r ban listname "<address to ban>"

Note that the ban list accepts regular expressions, so to ban an address and all suffixes, use ‘^address.*’ as the “address to ban”.

Lock Files

If a list stops handling traffic for some time, it may be due to a stale lock file. Mailman locks are in /srv/mailman/openstack/locks. If a lock is held for a list, then listname.lock will exist. The contents of the file will be the name of the lock sequence file which was used to obtain the lock. That file is in the form If the process id in that string no longer exists, it’s safe to assume the process died without cleaning up the lock. It should generally be safe to remove the lockfile in that case.