The first part of this book is a tutorial intended mainly for those with a limited understanding of sendmail . Its aim is to provide the novice with a general introduction to V8 sendmail .

Chapter 1, Introduction

Covers mail transfer agents and mail user agents, explains why sendmail is so complex, gives an overview of sendmail , and describes the differences between the header, body, and envelope of a mail message.

Chapter 2, Have a V8

Shows where and how to get the source for V8 sendmail and how to compile and test a working binary.

Chapter 3, The Roles of sendmail

Shows how sendmail processes aliases, queues messages for later transmission, does local and remote delivery, and runs in the background listening for incoming mail.

Chapter 4, How to Run sendmail

Illustrates use of the -b (become), -v (verbose), and -d (debugging) command-line switches.

Chapter 5, The sendmail.cf File

Provides a quick overview of all the commands found in the sendmail.cf file.

Chapter 6, The Mail Hub and Delivery Agents

Describes the hub approach and shows how M (delivery agent) commands can be used to forward mail to a central hub machine.

Chapter 7, Macros

Shows how text can be automatically propagated throughout the configuration file.

Chapter 8, Addresses and Rules

Describes a fictional network, then uses addresses in that network to illustrate rules and rule sets.

Chapter 9, Rule Set 0

Shows how rules in rule set 0 can select delivery agents and handle errors.

Chapter 10, Rule Set 3

Explains rule set 3, the first to rewrite all addresses.

Chapter 11, Rule Sets 1 and S=

Develops an S= rule set to make all mail appear as though it comes from the hub machine.

Chapter 12, Class

Shows how multiple values can be referenced with a single expression in the LHS of rules.

Chapter 13, Setting Options

Explains how options "tune" sendmail and offers a few suggestions.

Chapter 14, Headers, Precedence, and Trust

Completes the client.cf file by adding H , P , and T commands.

Chapter 15, Install and Test the client.cf File

Shows how to install the client.cf file as your working configuration file.

Chapter 16, The null.mc File and m4

Shows how m4 can be used to produce a client.cf file called nullclient .

Chapter 17, The Hub's Complex Rules

Concludes with a tour of a hub's major sendmail.cf file.