Thanks are of course due to Ethan Galstad and the Nagios Core development team for writing and maintaining Nagios Core, along with the reference manual against which the book's material was checked.

Thanks are also due to my loving partner Chantelle Potroz for her patience and support as this book was being written, and to my employer James Watts of Inspire Net Limited for permission to write it.

Thanks also to Shreerang Deshpande and Kedar Bhat from Packt for their patience and technical guidance during the book's development.

The map of Australia used for the background to the network map in Chapter 8, Managing Network Layout, is sampled from the public domain images available on the superb Natural Earth website, viewable at http://www.naturalearthdata.com/.