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

Comparing NRPE and SSH

Both SSH and NRPE are used to perform checks on remote machines. They can be set up to perform the same tasks. There are some differences and each solution is better in certain conditions.

SSH-based checks are easier to set up from a network and administrative perspective. All that is needed is to put a set of plugins on the machine, create a public key-based authentication, and you are all set to go! The main advantage of this method is that it uses the existing network protocol, which is usually running and enabled on all Unix-based machines. This way there's usually no changes in firewall configurations to pass traffic related to the Nagios checks if the server that Nagios is running on can already connect to other hosts using the SSH protocol.

Security and performance are the trade-offs. As SSH is a generic protocol, Nagios server can run any command on any of the machines that it can access. One way of limiting this problem is to set up a restricted shell for the...