In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning.

Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows:Code words in text are shown as follows: "The service-http service will define a check using check_http and optionally additional options for the check itself."

A block of code is set as follows:

 define service
 {
 use generic-service
 host_name mainrouter
 service_description OpenVPN
 check_command check_openvpn_remote
 check_interval 15
 max_check_attempts 3
 notification_interval 30
 notification_period 24x7
 }

Any command-line input or output is written as follows:

CHANGE_SVC_CHECK_COMMAND;linux1;PING;check_ping!500.0,50%

New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: "The shortcuts in this book are based on the Mac OS X 10.5+ scheme."