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

Defining object dependencies

It is a very common scenario that computers, or the applications they offer, depend on other objects to function properly. A typical example is that a web based application will depend on a database server. Another is a host behind a private network that depends on an OpenVPN service to work. As a system administrator, your job is to know these relations—if you plan to reinstall a database cluster, you need to let people know there will be downtime for almost all applications. Nagios should also be aware of such relations.

In such cases, it is very useful for system monitoring software to consider these dependencies. When analyzing which hosts and services are not working properly, it is good to analyze such dependencies and discard things that are not working because of other failures. This way, it will be easier for you to focus on the real problems. Therefore, it allows you to get to the root cause of any malfunction much faster.

Nagios allows you to define...