Nagios is a tool for system and network monitoring. It constantly checks other machines and various services on those machines. The main purpose of system monitoring is to detect and report any system not working properly as soon as possible--so that you are aware of problems before a user runs into them. It is a modular and flexible solution that uses plug-ins to do its job.

The book is an introduction to Nagios that will teach readers to use Nagios with its advanced features. At the same time, readers who have already used earlier versions of Nagios will also benefit because they will learn about the new and advanced features of Nagios 3.

What you will learn from this book?

• Understand system monitoring and how Nagios works
• Install and configure Nagios to administer your network and system
• Deploy agents and plug-ins, and monitor assets with advanced features of Nagios
• Notify users of current and future incidents to protect the availability, performance, and security of monitored assets
• Configure and work your way around Nagios's web interface
• Pass service and host check results over the network using NSCA
• Set up a working and usable distributed monitoring system using NSClient++ and NC_Net.
• Develop custom plug-ins responsible for doing the checks and analyzing results
• Use the web interface to manage scheduled downtimes for hosts and services
• Monitor UPS status over the network
• Use adaptive monitoring to modify various check-related parameters
• Use SSH and NRPE for doing remote checks
• Use SNMP to retrieve information from a device, set options, and also cover means for a device to notify other machines about a failure

Approach

This is a beginner-level book, which will introduce Nagios to System Administrators who are interested in monitoring their systems. The focus is on teaching system administrators to secure their systems in a much improved manner incorporating the newer features of Nagios.

It will teach Nagios beginners the basics of installation and configuration of version 3; it will show professionals who have already worked on earlier versions of Nagios the new features of Nagios like inheritance and also the new internal functions like better check scheduling.