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.
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.
Shows where and how to get the source for V8 sendmail and how to compile and test a working binary.
Shows how sendmail processes aliases, queues messages for later transmission, does local and remote delivery, and runs in the background listening for incoming mail.
Illustrates use of the
-v (verbose), and
-d (debugging) command-line switches.
Provides a quick overview of all the commands found in the sendmail.cf file.
Describes the hub approach and shows how
M (delivery agent)
commands can be used to forward mail to a central hub machine.
Shows how text can be automatically propagated throughout the configuration file.
Describes a fictional network, then uses addresses in that network to illustrate rules and rule sets.
Shows how rules in rule set 0 can select delivery agents and handle errors.
Explains rule set 3, the first to rewrite all addresses.
S= rule set to make all mail appear as though it
comes from the hub machine.
Shows how multiple values can be referenced with a single expression in the LHS of rules.
Explains how options "tune" sendmail and offers a few suggestions.
Completes the client.cf file by adding
Shows how to install the client.cf file as your working configuration file.
Shows how m4 can be used to produce a client.cf file called nullclient.
Concludes with a tour of a hub's major sendmail.cf file.