Application

CLI Commands

The Icinga 2 application is managed with different CLI sub commands. daemon takes care about loading the configuration files, running the application as daemon, etc. Other sub commands allow to enable features, generate and request TLS certificates or enter the debug console.

The main entry point for each CLI command parses the command line parameters and then triggers the required actions.

daemon CLI command

This CLI command loads the configuration files, starting with icinga2.conf. The configuration compiler parses the file and detects additional file includes, constants, and any other DSL specific declaration.

At this stage, the configuration will already be checked against the defined grammar in the scanner, and custom object validators will also be checked.

If the user provided -C/--validate, the CLI command returns with the validation exit code.

When running as daemon, additional parameters are checked, e.g. whether this application was triggered by a reload, needs to daemonize with fork() involved and update the object’s authority. The latter is important for HA-enabled cluster zones.