Mailing lists provide a convenient way to send a single email message to many recipients. They allow a nearly unlimited number of correspondents to carry on conversations through email. A server-based, centrally managed mailing list has many advantages over other mechanisms to send messages to multiple recipients. If you regularly send email to the same group of people, typing in lists of recipients is too tedious and prone to error to be practical. MUAs usually have a facility that lets you create personal aliases that associate an easily remembered name with a list of email addresses. Personal aliases are fine for an individual, but as soon as the list has to be shared with others, it is no longer a practical solution. Major advantages of centrally managed mailing lists are that changes are made in a single place, and the new information is immediately available to anyone sending messages to the list. Other advantages become evident when you use Mailing List Managers (MLMs) to administer the list, relieving administrators from manually updating addresses.
In this chapter we look at creating simple mailing lists within Postfix itself, and then configuring Postfix to deliver messages to MLMs for more sophisticated list management. In deciding whether or not to create your mailing list within Postfix or to use an MLM, consider how often the list has to be changed, who will make the changes, and whether you need some of the other features of an MLM, such as moderated lists and digest versions. MLMs allow users to subscribe and unsubscribe themselves and to make changes to their addresses, if necessary. If you have relatively static lists or users who come to you for subscribing and unsubscribing anyway, you probably don't need the overhead of an MLM. You can always run both flavors of lists, if that fits your environment.
There are many aspects and nuances to managing a mailing list. If you will be taking on the task, you should consult a text that deals specifically with mailing-list management such as Managing Mailing Lists by Alan Schwartz (O'Reilly).
General Configuration and Administration
Email and DNS
Local Delivery and POP/IMAP
Hosting Multiple Domains
Blocking Unsolicited Bulk Email
Transport Layer Security
Appendix A. Configuration Parameters
Appendix B. Postfix Commands
Appendix C. Compiling and Installing Postfix
Appendix D. Frequently Asked Questions