sendmail, 4th Edition

A List-Bounced Alias

There are many ways to handle bounced mail in managing a mailing list. One of the best ways for large lists is to create a bounce alias for a list:

list-bounce: :include:/usr/local/lists/list-bounce

When an address in the main list begins to bounce, move it from the main list’s file to the corresponding list-bounce file. Then send a message to that list nightly (via cron(8)), advising the users in it that they will soon be dropped. To prevent the bad addresses from deluging you with bounced mail, set up the return address and the envelope to be an alias that delivers to /dev/null:

black-hole:   /dev/null

Finally, arrange to include the following header in the outgoing message:

Precedence: junk

This prevents most sites from returning the message if it cannot be delivered.

Programs are available that can help to manage large and numerous mailing lists. We will cover them later in this chapter.