Icinga DB is a set of components for publishing, synchronizing and visualizing
monitoring data in the Icinga ecosystem, consisting of:

* Icinga DB Web which connects to both a Redis server and a database to view and
  work with most up-to-date monitoring data
* Icinga 2 with its Icinga DB feature enabled, responsible for publishing the
  data to the Redis server, i.e. configuration and its runtime updates, check
  results, state changes, downtimes, acknowledgements, notifications, and other
  events such as flapping
* And the Icinga DB daemon, which synchronizes the data between the Redis server
  and the database