manual/src/main/asciidoc/user-guide/introduction.adoc

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=== Introduction

Apache Karaf Decanter is monitoring solution running in Apache Karaf.

It's composed in three parts:

* Collectors are responsible of harvesting monitoring data. Decanter provides collectors to harvest different kind
of data. We have two kinds of collectors:
** Event Driven Collectors automatically react to events and send the event data to the Decanter appenders.
** Polled Collectors are periodically called by the Decanter Scheduler. They harvest data and send it to the Decanter
appenders
* Appenders receive the data from the collectors and are responsible to store the data into a given backend. Decanter
provides appenders depending of the backend storage that you want to use.
* Alerters is a special kind of appender. It receives all harvested data and checks on it. If a check fails, an alert event
is created and sent to alerters. Decanter provides alerters depending of the kind of notification that you want.

Apache Karaf Decanter provides Karaf features for each collector, appender, alerter.

The first thing to do is to add the Decanter features repository in Karaf:

----
karaf@root()> feature:repo-add mvn:org.apache.karaf.decanter/apache-karaf-decanter/2.0.0/xml/features
----

Or

----
karaf@root()> feature:repo-add decanter 2.0.0
----

Now, you have to install the collectors, appenders, and eventually alerters feature to match your need.