Part III: Administration

The third part of this tutorial covers the initial and day-to-day administration of sendmail. Of necessity, such administration must include other thorny issues, such as DNS and security, so we cover those subjects too.

• DNS and sendmail
• Shows how sendmail and the Domain Naming System interact, explains how to get them to work together, and offers help in taming the wild MX record.
• Security
• Explains why sendmail must run as root, then shows many ways to tighten security so that this will not be a problem.
• The Queue
• Shows how the queue is organized, how sendmail protects itself from bad files in the queue, and how to process and print the queue.
• Aliases
• Describes the aliases(5) file and the various parts that make it up. Also shows how to write a program to perform delivery, and how to manage and print the aliases database.
• Mailing Lists and ~/.forward
• Illustrates the ins and outs of managing mailing lists, shows how to set up a ~/.forward file, and presents solutions to various problems with both. This chapter also describes mailing lists and how to produce and manage them; it concludes with full coverage of the ~/.forward file.
• Logging and Statistics
• Explains how to use syslog(3) to log sendmail's activities and how to generate statistics from those logs. Describes the effect of signaling the daemon and the use of the -X command-line switch.