Book Image

Nagios Core Administration Cookbook - Second Edition

By : Tom Ryder
Book Image

Nagios Core Administration Cookbook - Second Edition

By: Tom Ryder

Overview of this book

Nagios Core is an open source monitoring framework suitable for any network that ensures both internal and customer-facing services are running correctly and manages notification and reporting behavior to diagnose and fix outages promptly. It allows very fine configuration of exactly when, where, what, and how to check network services to meet both the uptime goals of your network and systems team and the needs of your users. This book shows system and network administrators how to use Nagios Core to its fullest as a monitoring framework for checks on any kind of network services, from the smallest home network to much larger production multi-site services. You will discover that Nagios Core is capable of doing much more than pinging a host or to see whether websites respond. The recipes in this book will demonstrate how to leverage Nagios Core's advanced configuration, scripting hooks, reports, data retrieval, and extensibility to integrate it with your existing systems, and to make it the rock-solid center of your network monitoring world.
Table of Contents (18 chapters)
Nagios Core Administration Cookbook Second Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Setting the listening address for NRPE


In this recipe, we'll learn how to make NRPE listen on a specific IP address on a target host. This might be done on hosts with multiple interfaces in order to prevent spurious requests made to the nrpe daemon from untrusted interfaces, perhaps the public Internet. It could also be appropriate for making the daemon only listen on a trusted VPN interface.

This setup can be particularly useful when the server has an interface into a dedicated management network to which the monitoring server also has access, preventing the nrpe daemon from responding to requests on other interfaces unnecessarily and thereby closing a possible security hole.

Getting ready

You should have a target host configured for checking in a Nagios Core 4.0 or later monitoring server. The target host should be running the nrpe daemon and listening on all interfaces (which we'll fix). You can verify that nrpe is running with pgrep(1) or ps(1):

# pgrep nrpe
29964
# ps -e | grep [n]rpe...