sendmail Cookbook

Many system administrators feel uneasy when they have to change a sendmail configuration, and the worry is justified. The configuration languages are as intricate as any programming language, yet most administrators touch them only during installation or setup, so few get enough practice to become truly comfortable with them.

This book offers ready-made, step-by-step fixes for administrators who need a configuration problem solved quickly. Its example of setting up sendmail to relay mail for clients without becoming an open relay that spammers can exploit shows the approach. Each recipe identifies a problem, supplies the configuration code that handles it, and then walks through that code line by line, so readers can adapt it to their own environments rather than copying it blindly.

The opening chapter introduces the configuration languages and explains how to download and compile the sendmail distribution. A baseline configuration recipe follows, and many of the later recipes build on it. The remaining chapters are self-contained, each addressing an important sendmail function. The book gives extended coverage to STARTTLS and AUTH, each in its own chapter, and includes LDAP recipes throughout. Its overall aim is to save administrators time.