The Exim SMTP Mail Server
Official Guide for Release 4
by Philip Hazel
New second edition.

Email is the most widely used application on the Internet. Exim is rapidly becoming one of the most widely used mail servers, handling mail for tens of millions of users daily.

• Exim is free software.
• Exim is easy to configure. Its configuration files are easy to understand and edit.
• Exim is scalable. It runs on single-user desktop systems as well as on ISP servers handling millions of users.
• Exim is the default server already installed on many Linux systems, and it's available for countless versions of UNIX.
• Exim is fast.
• Exim is reliable. It is designed not to lose messages even if your server machine crashes.
• Exim is flexible. It supports lookups from LDAP servers, SQL databases, and other data sources, letting you automate maintenance and configuration. It can work with other tools, e.g. for virus-checking.

This book is a complete guide that will let you take full advantage of Exim on your network. If you are an email administrator or a designer or implementor of network applications, this book is an essential resource to help you:

• Deploy Exim as your SMTP email server throughout your organization.
• Configure a reliable mail service to meet the specific needs of your site.
• Manage your email system's daily operations, monitor its performance, interpret logs, and troubleshoot mail problems.
• Filter messages: save messages to files or divert them to other addresses, or check them for spam or viruses and delete them if they do.
• Tune your server to give optimal performance in your environment.
• Handle multiple domains for large organizations and "virtual" domains for ISP-type environments.
• Simplify your email management.
• Secure your email system to prevent unauthorized use and maintain the confidentiality of messages.