ISPConfig 3.1: The official manual by the creators of ISPConfig (English Edition)

On more than 400 pages, the ISPConfig manual covers the concept behind ISPConfig (admin, resellers, clients), explains how to install and update ISPConfig 3.1, includes a reference for all forms and form fields in the control panel together with examples of valid inputs, and provides tutorials for the most common tasks in ISPConfig 3.1.
It also lines out how to make your server more secure and comes with a troubleshooting section at the end.