Discovery HTTP interface
Discovery’s HTTP interface provides a web-management interface and two metric end-points. The web-management interface provides you with a central overview of licensing, component connectivity, and key performance metrics in your deployment. The metric end-points provide performance metrics in Prometheus and JSON format.
Web interface
Discovery’s web interface provides a visualisation of the components in your deployment, the connections between them, and key performance metrics.
Services pane
The Services pane lists all components connected to Discovery, with DataSource I/O rates (sent + received) displayed for all components except Liberator, which displays the number of current logins. I/O rates for Liberator are displayed in the connectivity diagram.
Connectivity diagram
The connectivity diagram illustrates components and the connections between them. Each component displays a DataSource I/O rate (sent + received) and a status disc indicating whether the component is UP or DOWN.
The thickness of connecting lines provides a graphical representation data throughput. Hover over a connection to reveal a tooltip with metrics for throughput (updates per second) and latency (milliseconds).
Connecting lines can also provide visual warnings of latency bottlenecks. Click the cog icon ( ) to open the Settings panel for the diagram. Set a Latency Threshold (ms) and choose a Latency Visualisation method.
In the screenshot below, the Latency Threshold has been set to 5ms and the Latency Visualisation method set to 'dash'. The latency between Transformer and Liberator is 10.5ms, which exceeds the new threshold, and so the connection is rendered as a dashed line.
Monitorables pane
Click on a component in the Services pane or Connectivity diagram for detailed metrics on the component.
The Liberator component also provides a separate status pane, Liberator Status, similar in style to the Liberator Status Page published by Liberator’s LiberatorWebsite blade:
Discovery retrieves metrics from components using the following interfaces:
| Component | Monitoring interface |
|---|---|
Liberator |
Sockmon |
Transformer |
Sockmon |
Java DataSource |
JMX |
Metrics
Discovery’s Spring Boot stack publishes JVM metrics at the following URIs:
| Format | URI | Example |
|---|---|---|
Prometheus |
/actuator/prometheus |
http://localhost:4567/actuator/prometheus |
JSON |
/actuator/metrics |
http://localhost:4567/actuator/metrics |
Configuring Discovery’s HTTP interface
To change Discovery’s HTTP port number, edit server.port in the Discovery server’s config/application.properties file.
To change which Spring Boot actuators are enabled, edit management-endpoints-web-exposure-include in the Discovery server’s config/application.properties file.