When creating or extending Nagios configurations to monitor large number of resources, spend some time planning the layout of your configuration. Some people recommend one file for each single definition, while others recommend storing things in a single file per host. We recommend keeping similar things in the same file and maintaining a directory-based set of files.
In this chapter, we have learned about setting up a directory and file naming structure for configurations. Using proper guidelines for naming and creating the files will help make the configuration maintainable when managing tens and thousands of hosts and services.
We have also defined dependencies, and covered how it can be used to make Nagios automatically notice when a problem is related to other host or when the service is not working properly. We have also learned how to use templates to help define a large number of objects, and how multiple inheritance can be used to automate the defined objects.