The qmail Handbook ISBN:1893115402 by Dave Sill Apress 2002 (492 pages) This guide begins with a discussion of qmail’s history, architecture and features, and then goes into a thorough investigation of the installation and configuration process Table of Contents The qmail Handbook Introduction Chapter 1 - Introducing qmail Chapter 2 - Installing qmail Configuring qmail: The Chapter 3 Basics Chapter 4 - Using qmail Chapter 5 - Managing qmail Chapter 6 - Troubleshooting qmail Configuring qmail: Chapter 7 Advanced Options Chapter 8 - Controlling Junk Mail Chapter 9 - Managing Mailing Lists Chapter 10 - Serving Mailboxes Chapter 11 - Hosting Virtual Domain and Users Understanding Advanced Chapter 12 Topics Appendix A - How qmail Works Appendix B - Related Packages Appendix C - How Internet Mail Works Appendix D - qmail Features Appendix E - Error Messages Appendix F - Gotchas Index List of Figures List of Tables List of Listings Back Cover Provides thorough instruction for installing, configuring, and optimizing qmail Includes coverage of secure networking, troubleshooting issues, and mailing list administration Covers what system administrators want to know by concentrating on qmail issues relevant to daily operation Includes instructions on how to filter spam before it reaches the client The qmail Handbook will guide system and mail administrators of all skill levels through installing, configuring, and maintaining the qmail server Author Dave Sill, a long-time qmail user and system administrator, as well as the author of the popular online tutorial “Life with qmail,” exposes readers to all practical aspects of working with this popular mail server This definitive guide begins with a discussion of qmail’s history, architecture, and features and then goes into a through investigation of the installation and configuration process Readers will learn how to install qmail on several operating systems and gain valuable insight into proper configuration, testing procedures, and performance tuning, all of which are integral to a properly functioning production environment mail server Readers will also learn how to administer users and mail, install filters, and oversee daily qmail operation and maintenance Throughout, Sill focuses on topics essential to all mail administrators, elaborating upon such subjects as configuring mailing list managers, controlling spam, secure networking, scanning for viruses, hosting virtual domains and users, and creating dial-up clients The qmail Handbook is the ultimate resource for administrators and developers needing to master the functionality of the powerful qmail software About the Author Dave Sill is a professional system administrator and technical support engineer with more than 15 years experience He’s been using qmail service since its first public release in 1996 and is the author of the popular online qmail guide “Life with qmail.” He’s also an active contributor to online qmail support groups, including the qmail mailing list and Usenet newsgroup The qmail Handbook DAVE SILL Copyright © 2002 by Dave Sill All rights reserved No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher ISBN (pbk): 1-893115-40-2 Printed and bound in the United States of America 12345678910 Trademarked names may appear in this book Rather than use a trademark symbol with every occurrence of a trademarked name, we use the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark Editorial Directors: Dan Appleman, Gary Cornell, Jason Gilmore, Karen Watterson Technical Reviewer: Charles Cabazon Project Manager: Grace Wong Copy Editor: Kim Wimpsett Production Editor: Sofia Marchant Compositor: Impressions Book and Journal Services, Inc Indexer: Ron Strauss Cover Designer: Tom Debolski Marketing Manager: Stephanie Rodriguez Distributed to the book trade in the United States by Springer-Verlag New York, Inc.,175 Fifth Avenue, New York, NY, 10010 and outside the United States by Springer-Verlag GmbH & Co KG, Tiergartenstr 17, 69112 Heidelberg, Germany In the United States, phone 1-800-SPRINGER, email , or visit http://www.springerny.com Outside the United States, fax +49 6221 345229, email , or visit http://www.springer.de For information on translations, please contact Apress directly at 901 Grayson Street, Suite 204, Berkeley, CA 94710 Phone 510-549-5938, fax: 510-549-5939, email , or visit http://www.apress.com The information in this book is distributed on an "as is" basis, without warranty Although every precaution has been taken in the preparation of this work, neither the author nor Apress shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in this work The source code for this book is available to readers at http://www.apress.com in the Downloads section You will need to answer questions pertaining to this book in order to successfully download the code For my mother Acknowledgments Thanks to dan bernstein for giving us qmail and many other packages including the daemontools and ucspi-tcp support utilities Thanks also to the many people who helped make my online guide "Life with qmail" what it is today and to the members of the qmail mailing list who have helped me learn a great deal about qmail over the years Thanks also to the fine folks at Apress: Jason Gilmore and Gary Cornell, for not only taking a chance on a first-time author but actively recruiting him; Grace Wong, for managing the project; Kim Wimpsett, for turning my crude writings into clear and consistent text; Tory McLearn and Sofia Marchant, for laying out the book; Stephanie Rodriguez, for her marketing efforts; and the many others behind the scenes who I didn't deal with directly Working with Apress was a joy: They were supportive and committed to producing a high-quality book Thanks to Charles Cazabon, the technical reviewer His suggestions were valuable and dramatically improved the quality of the finished product This will come as no surprise to anyone who has seen his contributions to the qmail list Finally, special thanks to my family and friends who encouraged, supported, and tolerated me throughout the project My wife, Mary Jane, convinced me to write this book even though she knew it would be painful for the family at times My children Andy, Rachel, and Erica enthusiastically supported me and helped out in many ways Andy tested the installation instructions in Chapter 2 on four Linux distributions and three BSD distributions My father took over most of my chores around the house and farm for six months in addition to his usual cooking and house/dog/kid-sitting duties My mother has supported me throughout my life Her strength is inspiring Many other friends and family members supported this effort Some are acknowledged throughout the book in the names used in examples, but I'm sure I left some out —Dave Sill, September 2001 About the Author Dave sill is a professional system administrator and technical support engineer with more than 15 years of experience He's been using qmail since its first public release in 1996 and is the author of the popular online qmail guide, "Life with qmail." He's also an active contributor to online qmail support groups including the qmail mailing list and Usenet newsgroup He lives with his wife, children, and an assortment of dogs, cats, cows, chickens, and turkeys on a 31-acre farm in east Tennessee When he has spare time, he brews his own beer and trains in Isshinryu karate About the Technical Reviewer Charles Cazabon is a software systems developer with 15 years of experience in computing and information technology He has been using and configuring qmail since 1998 and is the author of several free software programs, including getmail, queue-repair, and memtester He is also an active participant in the qmail mailing list He lives in Saskatoon, Canada, with his significant other, two salamanders, six hamsters, and two mice Introduction This book documents how to install, configure, and use qmail It will be most beneficial to system, network, and mail administrators, but it will also be helpful to users who want to read and send e-mail more effectively What Can You Expect to Learn from This Book? You can expect to learn the following: What qmail is, what it can do, and what it can't do How to install and configure a basic qmail server, including various support utilities How to use qmail as a regular user: controlling the disposition of incoming messages, formatting outgoing messages, and working with mailboxes in multiple formats How to manage a qmail server: setting up aliases, users, virtual domains, and mailing lists; troubleshooting; performance tuning; and controlling junk mail and other abuse How qmail works: not just what it does, but how it does it ... limiting the usage of the root UID to the small set of tasks that can only be done as root, qmail minimizes the potential for abuse Two qmail modules run as root: qmail- start and qmail- lspawn qmail- start needs root access to start qmail- lspawn as root, and... qmail uses separate programs that run under a set of qmail- specific UIDs, compartmentalizing their access These programs are designed to mistrust input from each other In other words, they don't blindly do what they're told: They validate their inputs before operating on them... It also describes the overall organization of the qmail suite, compares qmail to other Unix mailers, and lists other sources of qmail information and support Chapter 2, "Installing qmail, " describes step-by-step the installation of