Reliable, flexible, and configurable enough to solve the mail routing needs of any web site, sendmail has withstood the test of time, but has become no less daunting in its complexity. Even the most experienced system administrators have found it challenging to configure and difficult to understand. For help in unraveling its intricacies, sendmail administrators have turned unanimously to one reliable source--the bat book, or sendmail by Bryan Costales and the creator of sendmail, Eric Allman. Now in its third edition, this best-selling reference will help you master the most demanding version of sendmail yet.