Cluster capabilities

Cluster capabilities

Cluster administrators can use cluster capabilities to enable or disable optional components prior to installation. Cluster administrators can enable cluster capabilities at anytime after installation.

Cluster administrators cannot disable a cluster capability after it is enabled.

Selecting cluster capabilities

You can select cluster capabilities by following one of the installation methods that include customizing your cluster, such as “Installing a cluster on AWS with customizations” or “Installing a cluster on GCP with customizations”.

During a customized installation, you create an install-config.yaml file that contains the configuration parameters for your cluster.

If you customize your cluster by enabling or disabling specific cluster capabilities, you are responsible for manually maintaining your install-config.yaml file. New OKD updates might declare new capability handles for existing components, or introduce new components altogether. Users who customize their install-config.yaml file should consider periodically updating their install-config.yaml file as OKD is updated.

You can use the following configuration parameters to select cluster capabilities:

capabilities:
  baselineCapabilitySet: v4.11 (1)
  additionalEnabledCapabilities: (2)
  - CSISnapshot
  - Console
  - Storage

Defines a baseline set of capabilities to install. Valid values are None, vCurrent and v4.x. If you select None, all optional capabilities will be disabled. The default value is vCurrent, which enables all optional capabilities.

v4.x refers to any value up to and including the current cluster version. For example, valid values for a OKD 4.12 cluster are v4.11 and v4.12.

Defines a list of capabilities to explicitly enable. These will be enabled in addition to the capabilities specified in baselineCapabilitySet.

In this example, the default capability is set to v4.11. The additionalEnabledCapabilities field enables additional capabilities over the default v4.11 capability set.

The following table describes the baselineCapabilitySet values.

Table 1. Cluster capabilities `baselineCapabilitySet` values description
Value	Description
`vCurrent`	Specify this option when you want to automatically add new, default capabilities that are introduced in new releases.
`v4.11`	Specify this option when you want to enable the default capabilities for OKD 4.11. By specifying `v4.11`, capabilities that are introduced in newer versions of OKD are not enabled. The default capabilities in OKD 4.11 are `baremetal`, `MachineAPI`, `marketplace`, and `openshift-samples`.
`v4.12`	Specify this option when you want to enable the default capabilities for OKD 4.12. By specifying `v4.12`, capabilities that are introduced in newer versions of OKD are not enabled. The default capabilities in OKD 4.12 are `baremetal`, `MachineAPI`, `marketplace`, `openshift-samples`, `Console`, `Insights`, `Storage`, and `CSISnapshot`.
`v4.13`	Specify this option when you want to enable the default capabilities for OKD 4.13. By specifying `v4.13`, capabilities that are introduced in newer versions of OKD are not enabled. The default capabilities in OKD 4.13 are `baremetal`, `MachineAPI`, `marketplace`, `openshift-samples`, `Console`, `Insights`, `Storage`, `CSISnapshot`, and `NodeTuning`.
`v4.14`	Specify this option when you want to enable the default capabilities for OKD 4.14. By specifying `v4.14`, capabilities that are introduced in newer versions of OKD are not enabled. The default capabilities in OKD 4.14 are `baremetal`, `MachineAPI`, `marketplace`, `openshift-samples`, `Console`, `Insights`, `Storage`, `CSISnapshot`, `NodeTuning`, `ImageRegistry`, `Build`, and `DeploymentConfig`.
`None`	Specify when the other sets are too large, and you do not need any capabilities or want to fine-tune via `additionalEnabledCapabilities`.

Additional resources

Optional cluster capabilities in OKD 4.14

Currently, cluster Operators provide the features for these optional capabilities. The following summarizes the features provided by each capability and what functionality you lose if it is disabled.

Additional resources

Cluster Operators reference

Bare-metal capability

Purpose

The Cluster Baremetal Operator provides the features for the baremetal capability.

The Cluster Baremetal Operator (CBO) deploys all the components necessary to take a bare-metal server to a fully functioning worker node ready to run OKD compute nodes. The CBO ensures that the metal3 deployment, which consists of the Bare Metal Operator (BMO) and Ironic containers, runs on one of the control plane nodes within the OKD cluster. The CBO also listens for OKD updates to resources that it watches and takes appropriate action.

The bare-metal capability is required for deployments using installer-provisioned infrastructure. Disabling the bare-metal capability can result in unexpected problems with these deployments.

It is recommended that cluster administrators only disable the bare-metal capability during installations with user-provisioned infrastructure that do not have any BareMetalHost resources in the cluster.

If the bare-metal capability is disabled, the cluster cannot provision or manage bare-metal nodes. Only disable the capability if there are no BareMetalHost resources in your deployment. The baremetal capability depends on the MachineAPI capability. If you enable the baremetal capability, you must also enable MachineAPI.

Additional resources

Build capability

Purpose

The Build capability enables the Build API. The Build API manages the lifecycle of Build and BuildConfig objects.

If the Build capability is disabled, the cluster cannot use Build or BuildConfig resources. Disable the capability only if Build and BuildConfig resources are not required in the cluster.

Cluster storage capability

Purpose

The Cluster Storage Operator provides the features for the Storage capability.

The Cluster Storage Operator sets OKD cluster-wide storage defaults. It ensures a default storageclass exists for OKD clusters. It also installs Container Storage Interface (CSI) drivers which enable your cluster to use various storage backends.

If the cluster storage capability is disabled, the cluster will not have a default storageclass or any CSI drivers. Users with administrator privileges can create a default storageclass and manually install CSI drivers if the cluster storage capability is disabled.

Notes

The storage class that the Operator creates can be made non-default by editing its annotation, but this storage class cannot be deleted as long as the Operator runs.

Console capability

Purpose

The Console Operator provides the features for the Console capability.

The Console Operator installs and maintains the OKD web console on a cluster. The Console Operator is installed by default and automatically maintains a console.

Additional resources

Web console overview

CSI snapshot controller capability

Purpose

The Cluster CSI Snapshot Controller Operator provides the features for the CSISnapshot capability.

The Cluster CSI Snapshot Controller Operator installs and maintains the CSI Snapshot Controller. The CSI Snapshot Controller is responsible for watching the VolumeSnapshot CRD objects and manages the creation and deletion lifecycle of volume snapshots.

Additional resources

CSI volume snapshots

DeploymentConfig capability

Purpose

The DeploymentConfig capability enables and manages the DeploymentConfig API.

If the DeploymentConfig capability is disabled, the cluster cannot use DeploymentConfig resources. Disable the capability only if DeploymentConfig resources are not required in the cluster.

Insights capability

Purpose

The Insights Operator provides the features for the Insights capability.

The Insights Operator gathers OKD configuration data and sends it to Red Hat. The data is used to produce proactive insights recommendations about potential issues that a cluster might be exposed to. These insights are communicated to cluster administrators through Insights Advisor on console.redhat.com.

Notes

Insights Operator complements OKD Telemetry.

Additional resources

Using Insights Operator

Machine API capability

Purpose

The machine-api-operator, cluster-autoscaler-operator, and cluster-control-plane-machine-set-operator Operators provide the features for the MachineAPI capability. You can disable this capability only if you install a cluster with user-provisioned infrastructure.

The Machine API capability is responsible for all machine configuration and management in the cluster. If you disable the Machine API capability during installation, you need to manage all machine-related tasks manually.

Additional resources

Marketplace capability

Purpose

The Marketplace Operator provides the features for the marketplace capability.

The Marketplace Operator simplifies the process for bringing off-cluster Operators to your cluster by using a set of default Operator Lifecycle Manager (OLM) catalogs on the cluster. When the Marketplace Operator is installed, it creates the openshift-marketplace namespace. OLM ensures catalog sources installed in the openshift-marketplace namespace are available for all namespaces on the cluster.

If you disable the marketplace capability, the Marketplace Operator does not create the openshift-marketplace namespace. Catalog sources can still be configured and managed on the cluster manually, but OLM depends on the openshift-marketplace namespace in order to make catalogs available to all namespaces on the cluster. Users with elevated permissions to create namespaces prefixed with openshift-, such as system or cluster administrators, can manually create the openshift-marketplace namespace.

If you enable the marketplace capability, you can enable and disable individual catalogs by configuring the Marketplace Operator.

Additional resources

Red Hat-provided Operator catalogs

Node Tuning capability

Purpose

The Node Tuning Operator provides features for the NodeTuning capability.

The Node Tuning Operator helps you manage node-level tuning by orchestrating the TuneD daemon and achieves low latency performance by using the Performance Profile controller. The majority of high-performance applications require some level of kernel tuning. The Node Tuning Operator provides a unified management interface to users of node-level sysctls and more flexibility to add custom tuning specified by user needs.

If you disable the NodeTuning capability, some default tuning settings will not be applied to the control-plane nodes. This might limit the scalability and performance of large clusters with over 900 nodes or 900 routes.

Additional resources

Using the Node Tuning Operator

OpenShift samples capability

Purpose

The Cluster Samples Operator provides the features for the openshift-samples capability.

The Cluster Samples Operator manages the sample image streams and templates stored in the openshift namespace.

On initial start up, the Operator creates the default samples configuration resource to initiate the creation of the image streams and templates. The configuration object is a cluster scoped object with the key cluster and type configs.samples.

The image streams are the Fedora CoreOS (FCOS)-based OKD image streams pointing to images on registry.redhat.io. Similarly, the templates are those categorized as OKD templates.

If you disable the samples capability, users cannot access the image streams, samples, and templates it provides. Depending on your deployment, you might want to disable this component if you do not need it.

Additional resources

Configuring the Cluster Samples Operator

Cluster Image Registry capability

Purpose

The Cluster Image Registry Operator provides features for the ImageRegistry capability.

The Cluster Image Registry Operator manages a singleton instance of the OpenShift image registry. It manages all configuration of the registry, including creating storage.

On initial start up, the Operator creates a default image-registry resource instance based on the configuration detected in the cluster. This indicates what cloud storage type to use based on the cloud provider.

If insufficient information is available to define a complete image-registry resource, then an incomplete resource is defined and the Operator updates the resource status with information about what is missing.

The Cluster Image Registry Operator runs in the openshift-image-registry namespace and it also manages the registry instance in that location. All configuration and workload resources for the registry reside in that namespace.

If you disable the ImageRegistry capability, you can reduce the overall resource footprint of OKD in Telco environments. Depending on your deployment, you can disable this component if you do not need it.

Project

cluster-image-registry-operator

Additional resources

Image Registry Operator in OKD

Additional resources

Enabling cluster capabilities after installation