The Nagios plugins package offers a large variety of checks that can be performed to monitor your infrastructure. Whether you are an administrator of an IT company managing a large network or just want to monitor a small server room, these plugins will allow you to check the majority of the services that you are currently using.

In this chapter, we have learned how the plugins report status to Nagios using standard output and exit codes. We have also learned about the Nagios plugins project and the standard options for all of the plugins within the package.

We have also covered the generic communication plugins for checking remote host connectivity using ping, as well as generic TCP and UDP checking plugins. The chapter also described how to perform checks of standard networking protocols, such as e-mail, FTP, DHCP, website checking as well as Nagios process information.

We have also learned about checking various databases and how it can also be used to monitor the propagation of data...