1.8 KiB
Introduction
The OpenStack Telemetry plugin collects metrics about OpenStack resources and provides this data through Ceilometer API. This plugin implements all Ceilometer functionality except complex queries with InfluxDB and Elasticsearch as back ends for samples and events.
The OpenStack Telemetry plugin uses the following Ceilometer components:
- Polling agents (both central and computes)
- Notification agent
- Ceilometer API agent
Ceilometer Collector is not used. Instead, the Telemetry plugin uses its own tools to collect telemetry data from the Ceilometer agents.
The Telemetry plugin provides a better functionality if deployed
together with the Kafka plugin. In this case, the Telemetry plugin
configures Kafka as a message bus for the Ceilometer agents and
OpenStack services still send notifications to RabbitMQ. To process this
correctly, Ceilometer notification agent listens to Kafka and RabbitMQ
simultaneously. However, the Telemetry plugin works without Kafka as
well, but there are some scalability limitations. For more information,
see limitations.
Depending on the message broker installed, Hindsight or Heka are used as collectors:
- Hindsight -- fetches Ceilometer samples from Kafka and is installed on the same nodes as Kafka.
- Heka -- works with RabbitMQ and is installed on controller nodes under Pacemaker.
We recommend installing the Telemetry plugin along with the StackLight plugins. In this case, the Telemetry plugin will use the same databases as StackLight: InfluxDB and Elasticsearch. Otherwise, you can configure external storages.
By default, the OpenStack Telemetry plugin supports only sample and statistics API. However, you can enable full Ceilometer API support.
architecture