"A tremendous amount of information is available about sendmail.
But if you're in a hurry to just get it working, you don't have the
time to go through and digest it all. In this first installment in
a three-part series on sendmail, Carole discusses its
implementation on the firewall and focuses on features new to
"One of the greatest features of sendmail is the extreme
flexibility it provides the administrator. This is also one of its
worst features, the reason being that it is so often misconfigured.
Usually, a system administrator inherits a sendmail configuration
file that he or she is afraid to touch, lest it should break. Over
time, this file becomes hopelessly confusing, contradictory, and
"I began writing this column with the intention of providing a
simple, straightforward, "sendmail for dummies" approach. I ended
up appreciating how Bryan Costales must have felt when he wrote his
handbook, Sendmail for O'Reilly & Associates: Nothing is simple
in sendmail. I also learned to appreciate just how powerful and
flexible sendmail really is. It's worth learning. It's also worth a
few columns. I'll devote this month's column to discussing some of
the background and new features in sendmail 8.9.3 as well as how to
build the source code. Next month we'll look into the configuration
file. If there is enough interest, I will add a third column for
special situations and testing techniques."