Icinga 2 Config Language (DSL): Advanced Apply Rules
As many users of Icinga don’t know what the DSL has to offer, I’m going to show you how to use custom variables and apply for rules to make your life easier when writing configuration for your Icinga environment. In this example we will use custom variables on a host to configure a dynamic set of services to monitor multiple web services behind a reverse proxy. On the host we define a custom dictionary called http_vhosts and assign our virtual hosts to it.