Remote Administration of Project Lancelot Lists


This document explains how to administer Project Lancelot mailing lists by e-mail.


The methods described here require a version of Project Lancelot that is at least 0.2.99. We assume the following:

  • We are dealing with a list called list@….
  • The list was created by the system administrator of, who we shall call sysadmin@….
  • The list is to be administered remotely by the list administrator, who we shall call listadmin@….

We explain remote administration from the list administrator's point first, stipulating that everything has been set up correctly by the system administrator. Issues pertaining to list setup for remote administration are explained at the end of this document.

Remote Administration for List Administrators


List administrators can administer Project Lancelot by sending specially formatted e-mail messages to the list's administrative address, which is (by convention) list+admin@… (NOTE: Depending on local usage this address may be different in practice. In particular, it could be list-admin@…).

The following operations are allowed in principle:

  • Adding new subscribers to the list
  • Removing existing subscribers from the list
  • Changing the properties of an existing subscription
  • Obtaining a list of current subscribers
  • Retrieving and changing the list configuration

Any of these operations may be disallowed by the system administrator on a per-list basis.


It is clear that not just anybody is supposed to be able to change the mailing list. Therefore, as a list administrator you must authenticate a message to list+admin@… so that Project Lancelot can be reasonably sure that the message was, in fact, sent by you. There are currently two ways of doing so. Your system administrator will tell you which one is in operation.

  • Password authentication. The first line of text in your message must contain a secret password, as in »password secret«. (Your system administrator will be able to tell you the correct password.) This method is reasonably secure; it is what most other mailing list programs use, too.
  • GnuPG authentication. Your message must be signed using a GnuPG key whose public key is part of the list's administrator keyring. (If this is all Greek to you, then have your system administrator explain it in more detail.) This is about as secure as things get in e-mail.

Adding New Subscribers

To add a new subscriber, send an authenticated message like

  subscribe Alfred E. Newman <>

to list+admin@…. (Use

  password secret
  subscribe Alfred E. Newman <>

if your list uses password authentication and your password is secret. We won't bother repeating this in the other examples.)

You may leave off the name and give just the e-mail address:


You may add several subscribers either by giving multiple subscribe commands as in

  subscribe Alfred E. Newman <>
  subscribe Mickey Mouse <>

or by using an end marker as in

  subscribe <<END
  Alfred E. Newman <>
  Mickey Mouse <>

The second method is convenient if you have to add a lot of subscribers from a pre-existing list. Whatever comes after the << on the first line of the command must occur on a line by itself at the end of the list.

By default, subscribers are added as regular (non-digest) subscribers with no special options such as nomail. To add a subscriber as a digest or non-receiving subscriber, use

  subscribe --digest Alfred E. Newman <>
  subscribe --nomail Mickey Mouse <>

where »--digest« adds a digest subscriber, and »--nomail« adds an address that will not receive mail but will be allowed to submit messages to the list.

Removing Subscribers

To remove an existing subscriber, send a message like


You just need to provide the subscriber's e-mail address (their name will be ignored if given). There are no options for unsubscribing, but you can mass-unsubscribe a list of subscribers using the end-marker method as shown in the previous section.

Obtaining a List of Subscribers

To receive a message containing a list of subscribers to the mailing list, send a message like


You will receive a list looking like

  SA---- List Administrator
  S---n- Mickey Mouse
  S--d-- Alfred E. Newman

This list is ordered by domain and gives all subscribers' addresses and (if available) names. At the beginning of each line there is a word of flags telling which options are set for this subscription: S means the subscription is active. The next five characters are either - (if the corresponding option is not set) or one of the option letters A (list administrator), M (list moderator), d (digest subscriber), n (non-receiving subscriber), m (moderated subscriber).

You can give a search pattern on the list command in order to restrict the resulting list to a certain subset of the subscribers. For example,

  list *

would list just the subscribers in the domain.

Changing Subscription Options

(To be written.)

Retrieving and Changing the List Configuration

(To be written.)

Setting Up a List for Remote Administration

To enable remote administration for a list, the system administrator must add an appropriate workflow like

  mail.workflow.admin = authenticate(level=1) admin

This enables the list+admin@… address and requires password authentication (minimally -- GnuPG authentication would also be fine).

The system administrator must also designate one or more list administrators and configure a suitable authentication method for them:

  ll-subchange --admin --auth=password:secret \

There are some list configuration parameters that deal with remote administration:


If this is set, it contains a space-delimited list of commands that the remote administration interface will honour. Use this, e.g., to prevent list administrators from changing the list configuration.


If this is set, it contains a regular expression to be applied to the names of configuration parameters in a setconfig command. Any parameter whose name matches this regular expression will be ignored.


If this is set, it contains a regular expression to be applied to the names of configuration parameters in a setconfig command. Any parameter whose name does not match this regular expression will be ignored.

Last modified 11 years ago Last modified on Jan 5, 2007, 1:28:55 AM