OpenShift API Server Operator

The OpenShift API Server operator manages and updates the OpenShift API Server. The operator is based on OpenShift library-go framework and it is installed via Cluster Version Operator (CVO).

It contains the following sub-systems:

• Operator
• Configuration observer

By default, the operator exposes Prometheus metrics via metrics service. The metrics are collected from following components:

• OpenShift API Server Operator

Configuration

The configuration observer component is responsible for reacting on external configuration changes. For example, this allows external components (registry, etc..) to interact with the OpenShift API server configuration (OpenShiftAPIServerConfig custom resource).

Currently changes in following external components are being observed:

• cluster images.config.openshift.io custom resource
  • The observed CR resource is used to configure the imagePolicyConfig.internalRegistryHostname in Kubernetes API server configuration
• cluster projects.config.openshift.io custom resource
  • The observed CR resource is used to configure the Project request defaults
• cluster ingress.config.openshift.io custom resource
  • The observed CR resource is used to set routingConfig.subdomain in the OpenShift API server configuration.

The configuration for the OpenShift API server is the result of merging:

• a default config
• observed config (compare observed values above) spec.spec.unsupportedConfigOverrides from the openshiftapiserveroperatorconfig.

All of these are sparse configurations, i.e. unvalidated json snippets which are merged in order to form a valid configuration at the end.

Debugging

To gather all information necessary for debugging operator please use the must-gather tool.