Once the application is deployed to the production environment, we will need a way to constantly monitor the application's status, for example, by checking those Actuator's endpoints. When there is an outage or the system is in a critical status, for example, if the server is overloaded, we need a way to get notified.
Icinga 2 is a great fit for this purpose. It is an open source monitoring system. It uses monitoring plugins to check various services' statuses and generates performance data for reporting. Each plugin is a standalone command-line tool that performs a specific type of check. There are more than fifty standard plugins available on https://www.monitoring-plugins.org. Besides these plugins, you can also create your own check plugin. Icinga 2 also provides REST API and Web UI.
Because of the scope of this book, we will not go...
