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=========================================
Enabling Alarms for plugin metrics/meters
=========================================

This guide provides a description of what Aodh features are available when
either the collectd-gnocchi or the collectd-ceilometer plugin are enabled.
It provides a list of the alarms that can be created and how to create them.

collectd-gnocchi-plugin
-----------------------

There are three types of gnocchi based alarms that can be created using Aodh:

- gnocchi_resources_threshold
- gnocchi_aggregation_by_metrics_threshold
- gnocchi_aggregation_by_resources_threshold

 .. note::

       Currently, the metrics created by the collectd-gnocchi-plugin don't
       support the creation of gnocchi_resources_threshold alarms or
       gnocchi_aggregation_by_resources_threshold alarms.

To create a simple gnocchi_aggregation_by_metrics_threshold alarm:

- Type the following;

::

  aodh alarm create

- In the same command specify the name, type, metrics, threshold and
  aggregation method of your desired alarm. This alarm can be defined for one
  or a list of metrics.

::

  --name <ALARM_NAME>
  -t gnocchi_aggregation_by_metrics_threshold
  --threshold <THRESHOLD>
  --metrics <LIST_OF_METRICS>
  --aggregation-method <AGGREGATION_METHOD>


collectd-ceilometer-plugin
--------------------------

When this plugin is enabled threshold alarms can be defined for the new meters
that enabling this plugin generates.

- Threshold alarms can be created for meters via the following command;

::

  aodh alarm create
  --name <ALARM_NAME>
  -t threshold
  -m <METER_NAME>
  --threshold <THRESHOLD>


Event Alarms
------------

Event alarms can be created for either of these plugins. They can be triggered
by any type of event that can occur to either meters generated by the
ceilometer plugin or metrics from the gnocchi-plugin.

- To create event alarms enter the following command;

::

  aodh alarm create
  --name <ALARM_NAME>
  -t event
  --event-type <EVENT_TYPE>


Composite Alarms
----------------

Like event alarms, composite alarms can be created for both the gnocchi and
ceilometer plugins. A composite alarm is created by combining more than one
type of alarm. Hence you can combine gnocchi and ceilometer based alarms.

- Composite alarms are generated by the following command;

::

  aodh alarm create
  --name <ALARM_NAME>
  -t composite
  --composite-rule <COMPOSITE_RULE>