In OKD, cluster components are monitored by scraping metrics exposed through service endpoints. You can also configure metrics collection for user-defined projects. Metrics enable you to monitor how cluster components and your own workloads are performing.
You can define the metrics that you want to provide for your own workloads by using Prometheus client libraries at the application level.
In OKD, metrics are exposed through an HTTP service endpoint under the
/metrics canonical name. You can list all available metrics for a service by running a curl query against
http://<endpoint>/metrics. For instance, you can expose a route to the prometheus-example-app example application and then run the following to view all of its available metrics:
The OKD monitoring dashboard enables you to run Prometheus Query Language (PromQL) queries to examine metrics visualized on a plot. This functionality provides information about the state of a cluster and any user-defined workloads that you are monitoring.
As a cluster administrator, you can query metrics for all core OKD and user-defined projects.
As a developer, you must specify a project name when querying metrics. You must have the required privileges to view metrics for the selected project.