Book Image

Learning Nagios 3.0

Book Image

Learning Nagios 3.0

Overview of this book

Table of Contents (16 chapters)
Learning Nagios 3.0
Credits
About the Author
About the Reviewer
Preface

Freshness Checking


We now have distributed monitoring set up and the slave Nagios instances should be reporting results to the master Nagios daemon. Things should be working fine, and the main Web interface will be reporting up to-date information from all of the hosts and services being monitored.

Unfortunately, it is not always the case. In some cases, network connectivity can be down, the NSCA agents, daemon, or anything else on the network might fail temporarily, and the master Nagios instance may not even know about it. Because our basic assumption is that master Nagios instance is not responsible for monitoring the IT infrastructure, it needs to rely on other systems to do it. Configuration, as described earlier, does not take into account a situation where checks are not sent to the master instance.

Nagios offers a way to monitor whether results have come within a certain period of time. We can specify that if no report has come in within a certain amount of time, Nagios should treat...