1.4.8. Telemetry
The Telemetry service provides user-level usage data for OpenStack-based clouds that is used for customer billing, system monitoring, or alerts. Data can be collected by notifications sent by existing OpenStack components (for example, usage events emitted from Compute) or by polling the infrastructure (for example, libvirt).
Telemetry includes a storage daemon that communicates with authenticated agents via a trusted messaging system, to collect and aggregate data. Additionally, the service uses a plugin system, which makes it easy to add new monitors.
Table 1.10. Telemetry Service components
| Component | Description |
|---|---|
|
ceilometer-agent-compute
|
An agent that runs on each Compute node to poll for resource utilization statistics.
|
|
ceilometer-agent-central
|
An agent that runs on a central management server to poll for utilization statistics about resources not tied to instances or Compute nodes.
|
|
ceilometer-collector
|
An agent that runs on one or more central management servers to monitor the message queues. Notification messages are processed and turned into Telemetry messages, and sent back out on to the message bus using the appropriate topic. Telemetry messages are written to the data store without modification.
|
|
Mongo database
|
For collected usage sample data.
|
|
API Server
|
Runs on one or more central management servers to provide access to the data store's data. Only the Collector and the API server have access to the data store.
|