This book is primarily intended for system administrators who have been granted the dubious honor of administering email. But not all UNIX systems are managed by administrators. Many are managed by programmers, network engineers, and even by inexperienced users. It is our hope that this book satisfies all of you, no matter what your level of experience.
The true beginner should begin with Part 1, skipping ahead as needed.
The beginning system administrator should probably start with the tutorial in Part 1, then read Part 3 for help in understanding how to administer sendmail. Note that Parts 2 and 4 will reveal answers to many nagging questions that seem to be otherwise unanswered.
The experienced system administrator who wants to install and manage V8 sendmail should read Parts 2 and 3 first to gain the needed background. Then read Part 4.
UNIX gurus and sendmail specialists should find Part 4 to be of value (even Eric keeps a copy on his desk). In it, every arcane detail of sendmail is listed alphabetically. There is, for example, a single chapter dedicated to options, with every option listed and explained.
No matter what your level of expertise, the sheer size of this book forces us to assume that you are familiar with the day-to-day system workings of UNIX. If not, you must learn UNIX elsewhere.