The qmail Handbook

Chapter 1: Introducing qmail

Figure 1-1: How the sender, recipient, MUA, and MTA interact

Chapter 2: Installing qmail

Figure 2-1: Using symbolic links under /var/qmail

Chapter 4: Using qmail

Figure 4-1: Subscribing via a Web form

Chapter 7: Configuring qmail: Advanced Options

Figure 7-1: Example SMTP dialogue

Figure 7-2: Example of pipelined SMTP dialogue

Figure 7-3: Example of QMTP dialogue

Chapter 12: Understanding Advanced Topics

Figure 12-1: One SMTP connection, three messages

Figure 12-2: Three SMTP connections, one message each

Figure 12-3: One SMTP connection, three recipients

Figure 12-4: Distributing outgoing load

Figure 12-5: Distributing incoming load with MX records

Figure 12-6: A transparently distributed SMTP service

Figure 12-7: Distributing mail delivery

Figure 12-8: Distributed POP3/IMAP service

Appendix A: How qmail Works

Figure A-1: High-level qmail organization

Figure A-2: The receiving function

Figure A-3: The sending function