Book Image

Qmail Quickstarter: Install, Set Up and Run your own Email Server

Book Image

Qmail Quickstarter: Install, Set Up and Run your own Email Server

Overview of this book

This book starts with setting up a qmail server and takes you through virtualization, filtering, and other advanced features like hosting multiple domains, mailing lists, and SSL Encryption. Finally, it discusses the log files and how to make qmail work faster. Qmail is a secure, reliable, efficient, simple message transfer agent. It is designed for typical Internet-connected UNIX hosts. Qmail is the second most common SMTP server on the Internet, and has by far the fastest growth of any SMTP server. Qmail's straight-paper-path philosophy guarantees that a message, once accepted into the system, will never be lost. Qmail also optionally supports maildir, a new, super-reliable user mailbox format.
Table of Contents (13 chapters)

Basic Analysis


The qmail-send and qmail-smtpd logs easily demonstrate how busy the system is. Both logs provide a status indication of how many messages are handled concurrently at any given time and the limit on this concurrency. These status log entries combined with their timestamp give a picture of the load over time. Tracing a message through the system is relatively easy to do by hand: first, find the point where the message is injected into the queue, use its inode number to find the message's delivery attempts then use the delivery numbers of these attempts to locate the results of these attempts. When using a script to determine the same information, the potential reuse of the various identification numbers makes correct analysis rather tricky.

qmailanalog

To assist with analyzing the qmail-send logs, Dr. Bernstein wrote the qmailanalog software package (http://cr.yp.to/qmailanalog.html). This package excels in generating summaries of the qmail-send logs and has some limited ability...