Operators and Controllers

An OpenShift 4 cluster comes with many operators and controllers preinstalled. This page gives an overview of all installed operators on a new cluster and their purpose. Most of the operators are described to some extent in the official documentation under Red Hat Operators and available cluster customizations.


Description CRDs Namespaces

The Cluster Version Operator handles updates for a cluster.

  • ClusterVersion - is the configuration for automatic updates of the cluster

  • openshift-cluster-version

The DNS Operator deploys and manages CoreDNS on a cluster.

  • DNS.config.openshift.io/v1 - holds cluster-wide information about DNS

  • DNS.operator.openshift.io/v1 - manages the CoreDNS component

  • openshift-dns-operator

  • openshift-dns

The Service CA Operator manages the serving cert signer, ConfigMap CA bundle injector and generic CA bundle injector.

  • ServiceCA - provides information to configure an operator to manage the service cert controllers

  • openshift-service-ca-operator

  • openshift-service-ca

The Cloud Credential Operator manages cloud provider credentials on a cluster.

  • CredentialsRequest - request cloud credentials

  • openshift-cloud-credential-operator

Control Plane

Description CRDs Namespaces

The OpenShift API Server Operator installs and maintains the OpenShift API server on a cluster.

  • APIServer - holds configuration shared by all API servers in the system, among them especially kube-apiserver and openshift-apiserver

  • OpenShiftAPIServer - provides information to configure an operator to manage openshift-apiserver

  • openshift-apiserver-operator

  • openshift-apiserver

The OpenShift Controller Manager Operator manages and updates the Kubernetes API server.

  • OpenShiftControllerManager - provides information to configure an operator to manage openshift-controller-manager

  • openshift-controller-manager-operator

  • openshift-controller-manager

The cluster etcd operator handles the scaling of etcd during cluster bootstrap and regular operation.

  • Etcd - provides information to configure an operator to manage etcd

  • openshift-etcd-operator

  • openshift-etcd

The Kubernetes API Server Operator manages and updates the Kubernetes API server on a cluster.

  • KubeAPIServer - provides information to configure an operator to manage kube-apiserver

  • openshift-kube-apiserver-operator

  • openshift-kube-apiserver

The Kubernetes Controller Manager Operator manages and updates the Kubernetes Controller Manager on a cluster.

  • KubeControllerManager - provides information to configure an operator to manage kube-controller-manager

  • openshift-kube-controller-manager-operator

  • openshift-kube-controller-manager

The Kubernetes Scheduler Operator manages and updates the Kubernetes Scheduler on a cluster.

  • KubeScheduler - provides information to configure an operator to manage the scheduler

  • Scheduler - holds cluster-wide config information to run the Kubernetes scheduler

  • openshift-kube-scheduler-operator

  • openshift-kube-scheduler

The Kubernetes Storage Version Migrator Operator migrates stored data in etcd to the latest storage version.

  • StorageVersionMigration - represents a migration of stored data to the latest storage version

  • StorageState - state of the storage of a specific resource

  • openshift-kube-storage-version-migrator-operator

  • openshift-kube-storage-version-migrator


Description CRDs Namespaces

The Machine API Operator manages the lifecycle of machines in a cluster.

  • MachineSet - ensures that a specified number of machines replicas are running at any given time

  • Machine - is the Schema for the machines API

  • MachineHealthCheck - is the Schema for the machinehealthchecks API

  • openshift-machine-api

The Cluster Autoscaler Operator manages deployments of the OpenShift Cluster Autoscaler using the cluster-api provider.

  • ClusterAutoscaler - controls the configuration of the cluster’s autoscaler instance

  • MachineAutoscaler - targets a node group and manages the annotations to enable and configure autoscaling for that group

  • openshift-machine-api

The Machine Config Operator manages and applies configuration and updates of the base operating system and container runtime, including everything between the kernel and kubelet.

  • MachineConfigPool - track updates to a group of nodes

  • MachineConfig - contains Ignition configuration for a specific node

  • ControllerConfig - configuration for MachineConfigController

  • ContainerRuntimeConfig - describes a customized Container Runtime configuration

  • KubeletConfig - describes a customized Kubelet configuration

  • openshift-machine-config-operator

The Node Tuning Operator helps you manage node-level tuning by orchestrating the tuned daemon.

  • Tuned - collection of rules that allows cluster-wide deployment of node-level sysctls

  • Profile - specification for a tuned Profile

  • openshift-cluster-node-tuning-operator

The Cluster Machine Approver validates and approves CSRs for nodes attempting to join the cluster.

  • openshift-cluster-machine-approver


Description CRDs Namespaces Commodore

The Cluster Authentication Operator installs and maintains the Authentication Custom Resource in a cluster.

  • Authentication - specifies cluster-wide settings for authentication (like OAuth and webhook token authenticators)

  • OAuth - holds cluster-wide information about OAuth

  • openshift-authentication-operator

  • openshift-authentication



Description CRDs Namespaces

The Console Operator installs and maintains the OpenShift Container Platform web console on a cluster.

  • Console.operator.openshift.io/v1 - provides a means to configure an operator to manage the console

  • Console.config.openshift.io/v1 - cluster-wide configuration for the web console

  • ConsoleCLIDownload - extension for configuring openshift web console command line interface (CLI) do`wnloads`

  • ConsoleExternalLogLink - customizing OpenShift web console log links

  • ConsoleLink - customizing OpenShift web console links

  • ConsoleNotification - configuring openshift web console notifications

  • ConsoleYAMLSample - customizing OpenShift web console YAML samples

  • openshift-console-operator

  • openshift-console

The Cluster Storage Operator sets OpenShift Container Platform cluster-wide storage defaults.

  • CSISnapshotController - provides information to configure an operator to manage the CSI snapshot controller

  • openshift-cluster-storage-operator

The Cluster Image Registry Operator manages a singleton instance of the OpenShift Container Platform registry on a cluster.

  • Config.imageregistry.operator.openshift.io/v1 - configuration object for a registry instance managed by the registry operator

  • ImagePruner - configuration object for an image registry pruner managed by the registry operator

  • ImageContentSourcePolicy - holds cluster-wide information about how to handle registry mirror rules

  • openshift-image-registry

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

  • Config.samples.operator.openshift.io/v1 - configuration and detailed condition status for the Samples Operator

  • openshift-cluster-samples-operator

The Insights Operator gathers anonymized system configuration and reports it to Red Hat Insights.

  • openshift-insights

The Cluster Monitoring Operator manages and updates the Prometheus-based cluster monitoring stack on a cluster.

  • Alertmanager - describes an Alertmanager cluster

  • Prometheus - defines a Prometheus deployment

  • PrometheusRule - defines alerting rules for a Prometheus instance

  • PodMonitor - defines monitoring for a set of pods

  • ServiceMonitor - defines monitoring for a set of services

  • openshift-monitoring

The Cluster SVCAT API Server Operator installs and maintains a singleton instance of the OpenShift Service Catalog API Server on a cluster.

  • ServiceCatalogAPIServer - provides information to configure an operator to manage Service Catalog API Server

  • openshift-service-catalog-apiserver-operator

The Cluster SVCAT Controller Manager Operator installs and maintains a singleton instance of the OpenShift Service Catalog Controller Manager on a cluster.

  • ServiceCatalogControllerManager - provides information to configure an operator to manage Service Catalog Controller Manager

  • openshift-service-catalog-controller-manager-operator


Description CRDs Namespaces

The Ingress Operator configures and manages the OpenShift Container Platform router.

  • IngressController - manages ingress controller for the cluster

  • Ingress.config.openshift.io/v1 - holds cluster-wide information about ingress, including the default ingress domain used for routes

  • DNSRecord - is a DNS record managed in the zones defined by dns.config.openshift.io/cluster .spec.publicZone and .spec.privateZone

  • openshift-ingress-operator

  • openshift-ingress

The Cluster Network Operator installs and upgrades the networking components on a cluster.

  • Network.operator.openshift.io/v1 - describes the cluster’s desired network configuration

  • Network.config.openshift.io/v1 - holds cluster-wide information about Network

  • ClusterNetwork - describes the cluster network

  • OperatorPKI - simple certificate authority, internal to the network operator

  • EgressNetworkPolicy - describes the current egress network policy for a namespace

  • HostSubnet - describes the container subnet network on a node

  • NetNamespace - describes a single isolated network

  • NetworkAttachmentDefinition - used to setup the network attachment for Multus

  • IPPool - schema for Whereabouts IP address allocation

  • openshift-network-operator

  • openshift-sdn

  • openshift-multus

Operator Management

Description CRDs Namespaces

The Operator Lifecycle Manager (OLM) provides a declarative way to install, manage, and upgrade Operators and their dependencies on a cluster.

  • CatalogSourceConfig - is used to enable an operator present in the OperatorSource to your cluster

  • CatalogSource - is a repository of CSVs, CRDs, and operator packages

  • ClusterServiceVersion - tells OLM how to install an operator that can manage apps for a given version

  • InstallPlan - defines the installation of a set of operators

  • OperatorGroup - is the unit of multitenancy for OLM managed operators

  • OperatorSource - is used to define the external datastore we’re using to store operator bundles

  • Subscription - keeps operators up to date by tracking changes to Catalogs

  • openshift-operator-lifecycle-manager

The Marketplace Operator is a conduit to bring off-cluster Operators to your cluster.

  • PackageManifest - holds information about a package, which is a reference to one (or more) channels under a single package

  • OperatorHub - can be used to change the state of the default hub sources for OperatorHub

  • openshift-marketplace