Book Image

Learning Nagios - Third Edition

By : Wojciech Kocjan, Piotr Beltowski
Book Image

Learning Nagios - Third Edition

By: Wojciech Kocjan, Piotr Beltowski

Overview of this book

Nagios, a powerful and widely used IT monitoring and management software for problem -solving. It detects problems related to your organizations infrastructure and helps in resolving the issue before it impacts the business. Following the success of the previous edition, this book will continue to help you monitor the status of network devices and also notify the system administrators of network problems. Starting with the fundamentals, the book will teach you how to install and configure Nagios for your environment. The book helps you learn how to end downtimes, adding comments and generating reports using the built-in Web interface of Nagios. Moving on, you will be introduced to the third-party web interfaces and applications for checking the status and report specific information. As you progress further in Learning Nagios, you will focus on the standard set of Nagios plugins and also focus on teach you how to efficiently manage large configurations and using templates. Once you are up to speed with this, you will get to know the concept and working of notifications and events in Nagios. The book will then uncover the concept of passive check and shows how to use NRDP (Nagios Remote Data Processor). The focus then shifts to how Nagios checks can be run on remote machines and SNMP (Simple Network Management Protocol) can be used from Nagios. Lastly, the book will demonstrate how to extend Nagios by creating custom check commands, custom ways of notifying users and showing how passive checks and NRDP can be used to integrate your solutions with Nagios. By the end of the book, you will be a competent system administrator who could monitor mid-size businesses or even large scale enterprises.
Table of Contents (19 chapters)
Learning Nagios - Third Edition
About the Authors
About the Reviewer

Using adaptive monitoring

Nagios provides a very powerful feature called adaptive monitoring that allows the modification of various check-related parameters on the fly. This is done by sending a command to the Nagios external command pipe.

The first thing that can be changed on the fly is the command to be executed by Nagios, along with the attributes that will be passed to it-an equivalent of the check_command directive in the object definition. In order to do that we can use the CHANGE_HOST_CHECK_COMMAND or CHANGE_SVC_CHECK_COMMAND command. These require the hostname, or the hostname and service description, and the check command as arguments.

This can be used to actually change how hosts or services are checked, or to only modify parameters that are passed to the check commands-for example, a check for ping latency can be modified based on whether a primary or a backup connection is used. An example to change a check command of a service, which changes the command and its specified parameters...