⁠Chapter 12. OpenStack Telemetry Installation

12.1. Telemetry Service Overview
12.2. Overview of Telemetry Service Deployment
12.3. Install the Telemetry Service Packages
12.4. Create the Telemetry Identity Records
12.5. Configure Telemetry Service Authentication
12.6. Configure the Telemetry Database Connection
12.6.1. Configure and Launch the MongoDB Back-End
12.7. Configure the Compute Node
12.8. Configure Monitored Services
12.9. Launch the Telemetry API and Agents

⁠12.1. Telemetry Service Overview

The Telemetry service provides user-level usage data for OpenStack-based clouds, which can be 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 through a trusted messaging system, to collect and aggregate data. Additionally, the service uses a plug-in system, which makes it easy to add new monitors.
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Table 12.1. 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.
ceilometer-notification
An agent that pushes metrics to the collector service from various OpenStack services.
MongoDB database
For collected usage data from collector agents. Only the collector agents and the API server have access to the database.
API Server
Runs on one or more central management servers to provide access to data in the database.
RabbitMQ server (rabbitmq-server)
Provides the AMQP message queue. This server (also used by Block Storage) handles the OpenStack transaction management, including queuing, distribution, security, management, clustering, and federation. Messaging becomes especially important when an OpenStack deployment is scaled and its services are running on multiple machines.
Telemetry service dependencies
  • Each nova-compute node must have a ceilometer-compute agent deployed and running.
  • All nodes running the ceilometer-api service must have firewall rules granting appropriate access.
  • The ceilometer-central-agent cannot currently be horizontally scaled, so only a single instance of this service should be running at any given moment.
  • You can choose where to locate the additional Telemetry agents, as all intra-agent communication is either based on AMQP or REST calls to the ceilometer-api service; as is the case for the ceilometer-alarm-evaluator service.