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Feature Gates

This page contains an overview of the various feature gates an administrator can specify on different Kubernetes components.

See feature stages for an explanation of the stages for a feature.

Overview

Feature gates are a set of key=value pairs that describe Kubernetes features. You can turn these features on or off using the --feature-gates command line flag on each Kubernetes component.

Each Kubernetes component lets you enable or disable a set of feature gates that are relevant to that component. Use -h flag to see a full set of feature gates for all components. To set feature gates for a component, such as kubelet, use the --feature-gates flag assigned to a list of feature pairs:

--feature-gates="...,DynamicKubeletConfig=true"

The following tables are a summary of the feature gates that you can set on different Kubernetes components.

  • The "Since" column contains the Kubernetes release when a feature is introduced or its release stage is changed.
  • The "Until" column, if not empty, contains the last Kubernetes release in which you can still use a feature gate.
  • If a feature is in the Alpha or Beta state, you can find the feature listed in the Alpha/Beta feature gate table.
  • If a feature is stable you can find all stages for that feature listed in the Graduated/Deprecated feature gate table.
  • The Graduated/Deprecated feature gate table also lists deprecated and withdrawn features.

Feature gates for Alpha or Beta features

Feature gates for features in Alpha or Beta states
FeatureDefaultStageSinceUntil
APIListChunkingfalseAlpha1.81.8
APIListChunkingtrueBeta1.9
APIPriorityAndFairnessfalseAlpha1.171.19
APIPriorityAndFairnesstrueBeta1.20
APIResponseCompressionfalseAlpha1.71.15
APIResponseCompressionfalseBeta1.16
APIServerIdentityfalseAlpha1.20
AllowInsecureBackendProxytrueBeta1.17
AnyVolumeDataSourcefalseAlpha1.18
AppArmortrueBeta1.4
BalanceAttachedNodeVolumesfalseAlpha1.11
BoundServiceAccountTokenVolumefalseAlpha1.13
CPUManagerfalseAlpha1.81.9
CPUManagertrueBeta1.10
CRIContainerLogRotationfalseAlpha1.101.10
CRIContainerLogRotationtrueBeta1.11
CSIInlineVolumefalseAlpha1.151.15
CSIInlineVolumetrueBeta1.16-
CSIMigrationfalseAlpha1.141.16
CSIMigrationtrueBeta1.17
CSIMigrationAWSfalseAlpha1.14
CSIMigrationAWSfalseBeta1.17
CSIMigrationAWSCompletefalseAlpha1.17
CSIMigrationAzureDiskfalseAlpha1.151.18
CSIMigrationAzureDiskfalseBeta1.19
CSIMigrationAzureDiskCompletefalseAlpha1.17
CSIMigrationAzureFilefalseAlpha1.15
CSIMigrationAzureFileCompletefalseAlpha1.17
CSIMigrationGCEfalseAlpha1.141.16
CSIMigrationGCEfalseBeta1.17
CSIMigrationGCECompletefalseAlpha1.17
CSIMigrationOpenStackfalseAlpha1.141.17
CSIMigrationOpenStacktrueBeta1.18
CSIMigrationOpenStackCompletefalseAlpha1.17
CSIMigrationvSpherefalseBeta1.19
CSIMigrationvSphereCompletefalseBeta1.19
CSIServiceAccountTokenfalseAlpha1.20
CSIStorageCapacityfalseAlpha1.19
CSIVolumeFSGroupPolicyfalseAlpha1.191.19
CSIVolumeFSGroupPolicytrueBeta1.20
ConfigurableFSGroupPolicyfalseAlpha1.181.19
ConfigurableFSGroupPolicytrueBeta1.20
CronJobControllerV2falseAlpha1.20
CustomCPUCFSQuotaPeriodfalseAlpha1.12
DefaultPodTopologySpreadfalseAlpha1.191.19
DefaultPodTopologySpreadtrueBeta1.20
DevicePluginsfalseAlpha1.81.9
DevicePluginstrueBeta1.10
DisableAcceleratorUsageMetricsfalseAlpha1.191.19
DisableAcceleratorUsageMetricstrueBeta1.20
DownwardAPIHugePagesfalseAlpha1.20
DynamicKubeletConfigfalseAlpha1.41.10
DynamicKubeletConfigtrueBeta1.11
EfficientWatchResumptionfalseAlpha1.20
EndpointSlicefalseAlpha1.161.16
EndpointSlicefalseBeta1.17
EndpointSlicetrueBeta1.18
EndpointSliceNodeNamefalseAlpha1.20
EndpointSliceProxyingfalseAlpha1.181.18
EndpointSliceProxyingtrueBeta1.19
EndpointSliceTerminatingConditionfalseAlpha1.20
EphemeralContainersfalseAlpha1.16
ExpandCSIVolumesfalseAlpha1.141.15
ExpandCSIVolumestrueBeta1.16
ExpandInUsePersistentVolumesfalseAlpha1.111.14
ExpandInUsePersistentVolumestrueBeta1.15
ExpandPersistentVolumesfalseAlpha1.81.10
ExpandPersistentVolumestrueBeta1.11
ExperimentalHostUserNamespaceDefaultingfalseBeta1.5
GenericEphemeralVolumefalseAlpha1.19
GracefulNodeShutdownfalseAlpha1.20
HPAContainerMetricsfalseAlpha1.20
HPAScaleToZerofalseAlpha1.16
HugePageStorageMediumSizefalseAlpha1.181.18
HugePageStorageMediumSizetrueBeta1.19
IPv6DualStackfalseAlpha1.15
ImmutableEphemeralVolumesfalseAlpha1.181.18
ImmutableEphemeralVolumestrueBeta1.19
KubeletCredentialProvidersfalseAlpha1.20
KubeletPodResourcestrueAlpha1.131.14
KubeletPodResourcestrueBeta1.15
LegacyNodeRoleBehaviorfalseAlpha1.161.18
LegacyNodeRoleBehaviortrueTrue1.19
LocalStorageCapacityIsolationfalseAlpha1.71.9
LocalStorageCapacityIsolationtrueBeta1.10
LocalStorageCapacityIsolationFSQuotaMonitoringfalseAlpha1.15
MixedProtocolLBServicefalseAlpha1.20
NodeDisruptionExclusionfalseAlpha1.161.18
NodeDisruptionExclusiontrueBeta1.19
NonPreemptingPriorityfalseAlpha1.151.18
NonPreemptingPrioritytrueBeta1.19
PodDisruptionBudgetfalseAlpha1.31.4
PodDisruptionBudgettrueBeta1.5
PodOverheadfalseAlpha1.161.17
PodOverheadtrueBeta1.18
ProcMountTypefalseAlpha1.12
QOSReservedfalseAlpha1.11
RemainingItemCountfalseAlpha1.15
RemoveSelfLinkfalseAlpha1.161.19
RemoveSelfLinktrueBeta1.20
RootCAConfigMapfalseAlpha1.131.19
RootCAConfigMaptrueBeta1.20
RotateKubeletServerCertificatefalseAlpha1.71.11
RotateKubeletServerCertificatetrueBeta1.12
RunAsGrouptrueBeta1.14
SCTPSupportfalseAlpha1.121.18
SCTPSupporttrueBeta1.19
ServerSideApplyfalseAlpha1.141.15
ServerSideApplytrueBeta1.16
ServiceAccountIssuerDiscoveryfalseAlpha1.181.19
ServiceAccountIssuerDiscoverytrueBeta1.20
ServiceLBNodePortControlfalseAlpha1.20
ServiceNodeExclusionfalseAlpha1.81.18
ServiceNodeExclusiontrueBeta1.19
ServiceTopologyfalseAlpha1.17
SetHostnameAsFQDNfalseAlpha1.191.19
SetHostnameAsFQDNtrueBeta1.20
SizeMemoryBackedVolumesfalseAlpha1.20
StorageVersionAPIfalseAlpha1.20
StorageVersionHashfalseAlpha1.141.14
StorageVersionHashtrueBeta1.15
SysctlstrueBeta1.11
TTLAfterFinishedfalseAlpha1.12
TopologyManagerfalseAlpha1.161.17
TopologyManagertrueBeta1.18
ValidateProxyRedirectsfalseAlpha1.121.13
ValidateProxyRedirectstrueBeta1.14
WarningHeaderstrueBeta1.19
WinDSRfalseAlpha1.14
WinOverlayfalseAlpha1.141.19
WinOverlaytrueBeta1.20
WindowsEndpointSliceProxyingfalseAlpha1.19

Feature gates for graduated or deprecated features

Feature Gates for Graduated or Deprecated Features
FeatureDefaultStageSinceUntil
AcceleratorsfalseAlpha1.61.10
Accelerators-Deprecated1.11-
AdvancedAuditingfalseAlpha1.71.7
AdvancedAuditingtrueBeta1.81.11
AdvancedAuditingtrueGA1.12-
AffinityInAnnotationsfalseAlpha1.61.7
AffinityInAnnotations-Deprecated1.8-
AllowExtTrafficLocalEndpointsfalseBeta1.41.6
AllowExtTrafficLocalEndpointstrueGA1.7-
BlockVolumefalseAlpha1.91.12
BlockVolumetrueBeta1.131.17
BlockVolumetrueGA1.18-
CSIBlockVolumefalseAlpha1.111.13
CSIBlockVolumetrueBeta1.141.17
CSIBlockVolumetrueGA1.18-
CSIDriverRegistryfalseAlpha1.121.13
CSIDriverRegistrytrueBeta1.141.17
CSIDriverRegistrytrueGA1.18
CSINodeInfofalseAlpha1.121.13
CSINodeInfotrueBeta1.141.16
CSINodeInfotrueGA1.17
AttachVolumeLimitfalseAlpha1.111.11
AttachVolumeLimittrueBeta1.121.16
AttachVolumeLimittrueGA1.17-
CSIPersistentVolumefalseAlpha1.91.9
CSIPersistentVolumetrueBeta1.101.12
CSIPersistentVolumetrueGA1.13-
CustomPodDNSfalseAlpha1.91.9
CustomPodDNStrueBeta1.101.13
CustomPodDNStrueGA1.14-
CustomResourceDefaultingfalseAlpha1.151.15
CustomResourceDefaultingtrueBeta1.161.16
CustomResourceDefaultingtrueGA1.17-
CustomResourcePublishOpenAPIfalseAlpha1.141.14
CustomResourcePublishOpenAPItrueBeta1.151.15
CustomResourcePublishOpenAPItrueGA1.16-
CustomResourceSubresourcesfalseAlpha1.101.10
CustomResourceSubresourcestrueBeta1.111.15
CustomResourceSubresourcestrueGA1.16-
CustomResourceValidationfalseAlpha1.81.8
CustomResourceValidationtrueBeta1.91.15
CustomResourceValidationtrueGA1.16-
CustomResourceWebhookConversionfalseAlpha1.131.14
CustomResourceWebhookConversiontrueBeta1.151.15
CustomResourceWebhookConversiontrueGA1.16-
DryRunfalseAlpha1.121.12
DryRuntrueBeta1.131.18
DryRuntrueGA1.19-
DynamicAuditingfalseAlpha1.131.18
DynamicAuditing-Deprecated1.19-
DynamicProvisioningSchedulingfalseAlpha1.111.11
DynamicProvisioningScheduling-Deprecated1.12-
DynamicVolumeProvisioningtrueAlpha1.31.7
DynamicVolumeProvisioningtrueGA1.8-
EnableAggregatedDiscoveryTimeouttrueDeprecated1.16-
EnableEquivalenceClassCachefalseAlpha1.81.14
EnableEquivalenceClassCache-Deprecated1.15-
ExperimentalCriticalPodAnnotationfalseAlpha1.51.12
ExperimentalCriticalPodAnnotationfalseDeprecated1.13-
EvenPodsSpreadfalseAlpha1.161.17
EvenPodsSpreadtrueBeta1.181.18
EvenPodsSpreadtrueGA1.19-
ExecProbeTimeouttrueGA1.20-
GCERegionalPersistentDisktrueBeta1.101.12
GCERegionalPersistentDisktrueGA1.13-
HugePagesfalseAlpha1.81.9
HugePagestrueBeta1.101.13
HugePagestrueGA1.14-
HyperVContainerfalseAlpha1.101.19
HyperVContainerfalseDeprecated1.20-
InitializersfalseAlpha1.71.13
Initializers-Deprecated1.14-
KubeletConfigFilefalseAlpha1.81.9
KubeletConfigFile-Deprecated1.10-
KubeletPluginsWatcherfalseAlpha1.111.11
KubeletPluginsWatchertrueBeta1.121.12
KubeletPluginsWatchertrueGA1.13-
KubeletPodResourcesfalseAlpha1.131.14
KubeletPodResourcestrueBeta1.15
KubeletPodResourcestrueGA1.20
MountContainersfalseAlpha1.91.16
MountContainersfalseDeprecated1.17-
MountPropagationfalseAlpha1.81.9
MountPropagationtrueBeta1.101.11
MountPropagationtrueGA1.12-
NodeLeasefalseAlpha1.121.13
NodeLeasetrueBeta1.141.16
NodeLeasetrueGA1.17-
PVCProtectionfalseAlpha1.91.9
PVCProtection-Deprecated1.10-
PersistentLocalVolumesfalseAlpha1.71.9
PersistentLocalVolumestrueBeta1.101.13
PersistentLocalVolumestrueGA1.14-
PodPriorityfalseAlpha1.81.10
PodPrioritytrueBeta1.111.13
PodPrioritytrueGA1.14-
PodReadinessGatesfalseAlpha1.111.11
PodReadinessGatestrueBeta1.121.13
PodReadinessGatestrueGA1.14-
PodShareProcessNamespacefalseAlpha1.101.11
PodShareProcessNamespacetrueBeta1.121.16
PodShareProcessNamespacetrueGA1.17-
RequestManagementfalseAlpha1.151.16
ResourceLimitsPriorityFunctionfalseAlpha1.91.18
ResourceLimitsPriorityFunction-Deprecated1.19-
ResourceQuotaScopeSelectorsfalseAlpha1.111.11
ResourceQuotaScopeSelectorstrueBeta1.121.16
ResourceQuotaScopeSelectorstrueGA1.17-
RotateKubeletClientCertificatetrueBeta1.81.18
RotateKubeletClientCertificatetrueGA1.19-
RuntimeClassfalseAlpha1.121.13
RuntimeClasstrueBeta1.141.19
RuntimeClasstrueGA1.20-
ScheduleDaemonSetPodsfalseAlpha1.111.11
ScheduleDaemonSetPodstrueBeta1.121.16
ScheduleDaemonSetPodstrueGA1.17-
SCTPSupportfalseAlpha1.121.18
SCTPSupporttrueBeta1.191.19
SCTPSupporttrueGA1.20-
ServiceAppProtocolfalseAlpha1.181.18
ServiceAppProtocoltrueBeta1.19
ServiceAppProtocoltrueGA1.20-
ServiceLoadBalancerFinalizerfalseAlpha1.151.15
ServiceLoadBalancerFinalizertrueBeta1.161.16
ServiceLoadBalancerFinalizertrueGA1.17-
StartupProbefalseAlpha1.161.17
StartupProbetrueBeta1.181.19
StartupProbetrueGA1.20-
StorageObjectInUseProtectiontrueBeta1.101.10
StorageObjectInUseProtectiontrueGA1.11-
StreamingProxyRedirectsfalseBeta1.51.5
StreamingProxyRedirectstrueBeta1.61.18
StreamingProxyRedirects-Deprecated1.19-
SupportIPVSProxyModefalseAlpha1.81.8
SupportIPVSProxyModefalseBeta1.91.9
SupportIPVSProxyModetrueBeta1.101.10
SupportIPVSProxyModetrueGA1.11-
SupportNodePidsLimitfalseAlpha1.141.14
SupportNodePidsLimittrueBeta1.151.19
SupportNodePidsLimittrueGA1.20-
SupportPodPidsLimitfalseAlpha1.101.13
SupportPodPidsLimittrueBeta1.141.19
SupportPodPidsLimittrueGA1.20-
TaintBasedEvictionsfalseAlpha1.61.12
TaintBasedEvictionstrueBeta1.131.17
TaintBasedEvictionstrueGA1.18-
TaintNodesByConditionfalseAlpha1.81.11
TaintNodesByConditiontrueBeta1.121.16
TaintNodesByConditiontrueGA1.17-
TokenRequestfalseAlpha1.101.11
TokenRequesttrueBeta1.121.19
TokenRequesttrueGA1.20-
TokenRequestProjectionfalseAlpha1.111.11
TokenRequestProjectiontrueBeta1.121.19
TokenRequestProjectiontrueGA1.20-
VolumeSnapshotDataSourcefalseAlpha1.121.16
VolumeSnapshotDataSourcetrueBeta1.171.19
VolumeSnapshotDataSourcetrueGA1.20-
VolumePVCDataSourcefalseAlpha1.151.15
VolumePVCDataSourcetrueBeta1.161.17
VolumePVCDataSourcetrueGA1.18-
VolumeSchedulingfalseAlpha1.91.9
VolumeSchedulingtrueBeta1.101.12
VolumeSchedulingtrueGA1.13-
VolumeSubpathtrueGA1.10-
VolumeSubpathEnvExpansionfalseAlpha1.141.14
VolumeSubpathEnvExpansiontrueBeta1.151.16
VolumeSubpathEnvExpansiontrueGA1.17-
WatchBookmarkfalseAlpha1.151.15
WatchBookmarktrueBeta1.161.16
WatchBookmarktrueGA1.17-
WindowsGMSAfalseAlpha1.141.15
WindowsGMSAtrueBeta1.161.17
WindowsGMSAtrueGA1.18-
WindowsRunAsUserNamefalseAlpha1.161.16
WindowsRunAsUserNametrueBeta1.171.17
WindowsRunAsUserNametrueGA1.18-

Using a feature

Feature stages

A feature can be in Alpha, Beta or GA stage. An Alpha feature means:

  • Disabled by default.
  • Might be buggy. Enabling the feature may expose bugs.
  • Support for feature may be dropped at any time without notice.
  • The API may change in incompatible ways in a later software release without notice.
  • Recommended for use only in short-lived testing clusters, due to increased risk of bugs and lack of long-term support.

A Beta feature means:

  • Enabled by default.
  • The feature is well tested. Enabling the feature is considered safe.
  • Support for the overall feature will not be dropped, though details may change.
  • The schema and/or semantics of objects may change in incompatible ways in a subsequent beta or stable release. When this happens, we will provide instructions for migrating to the next version. This may require deleting, editing, and re-creating API objects. The editing process may require some thought. This may require downtime for applications that rely on the feature.
  • Recommended for only non-business-critical uses because of potential for incompatible changes in subsequent releases. If you have multiple clusters that can be upgraded independently, you may be able to relax this restriction.
Note: Please do try Beta features and give feedback on them! After they exit beta, it may not be practical for us to make more changes.

A General Availability (GA) feature is also referred to as a stable feature. It means:

  • The feature is always enabled; you cannot disable it.
  • The corresponding feature gate is no longer needed.
  • Stable versions of features will appear in released software for many subsequent versions.

List of feature gates

Each feature gate is designed for enabling/disabling a specific feature:

  • APIListChunking: Enable the API clients to retrieve (LIST or GET) resources from API server in chunks.
  • APIPriorityAndFairness: Enable managing request concurrency with prioritization and fairness at each server. (Renamed from RequestManagement)
  • APIResponseCompression: Compress the API responses for LIST or GET requests.
  • APIServerIdentity: Assign each API server an ID in a cluster.
  • Accelerators: Enable Nvidia GPU support when using Docker
  • AdvancedAuditing: Enable advanced auditing
  • AffinityInAnnotations(deprecated): Enable setting Pod affinity or anti-affinity.
  • AllowExtTrafficLocalEndpoints: Enable a service to route external requests to node local endpoints.
  • AllowInsecureBackendProxy: Enable the users to skip TLS verification of kubelets on Pod log requests.
  • AnyVolumeDataSource: Enable use of any custom resource as the DataSource of a PVC.
  • AppArmor: Enable AppArmor based mandatory access control on Linux nodes when using Docker. See AppArmor Tutorial for more details.
  • AttachVolumeLimit: Enable volume plugins to report limits on number of volumes that can be attached to a node. See dynamic volume limits for more details.
  • BalanceAttachedNodeVolumes: Include volume count on node to be considered for balanced resource allocation while scheduling. A node which has closer CPU, memory utilization, and volume count is favored by the scheduler while making decisions.
  • BlockVolume: Enable the definition and consumption of raw block devices in Pods. See Raw Block Volume Support for more details.
  • BoundServiceAccountTokenVolume: Migrate ServiceAccount volumes to use a projected volume consisting of a ServiceAccountTokenVolumeProjection. Cluster admins can use metric serviceaccount_stale_tokens_total to monitor workloads that are depending on the extended tokens. If there are no such workloads, turn off extended tokens by starting kube-apiserver with flag --service-account-extend-token-expiration=false. Check Bound Service Account Tokens for more details.
  • CPUManager: Enable container level CPU affinity support, see CPU Management Policies.
  • CRIContainerLogRotation: Enable container log rotation for cri container runtime.
  • CSIBlockVolume: Enable external CSI volume drivers to support block storage. See the csi raw block volume support documentation for more details.
  • CSIDriverRegistry: Enable all logic related to the CSIDriver API object in csi.storage.k8s.io.
  • CSIInlineVolume: Enable CSI Inline volumes support for pods.
  • CSIMigration: Enables shims and translation logic to route volume operations from in-tree plugins to corresponding pre-installed CSI plugins
  • CSIMigrationAWS: Enables shims and translation logic to route volume operations from the AWS-EBS in-tree plugin to EBS CSI plugin. Supports falling back to in-tree EBS plugin if a node does not have EBS CSI plugin installed and configured. Requires CSIMigration feature flag enabled.
  • CSIMigrationAWSComplete: Stops registering the EBS in-tree plugin in kubelet and volume controllers and enables shims and translation logic to route volume operations from the AWS-EBS in-tree plugin to EBS CSI plugin. Requires CSIMigration and CSIMigrationAWS feature flags enabled and EBS CSI plugin installed and configured on all nodes in the cluster.
  • CSIMigrationAzureDisk: Enables shims and translation logic to route volume operations from the Azure-Disk in-tree plugin to AzureDisk CSI plugin. Supports falling back to in-tree AzureDisk plugin if a node does not have AzureDisk CSI plugin installed and configured. Requires CSIMigration feature flag enabled.
  • CSIMigrationAzureDiskComplete: Stops registering the Azure-Disk in-tree plugin in kubelet and volume controllers and enables shims and translation logic to route volume operations from the Azure-Disk in-tree plugin to AzureDisk CSI plugin. Requires CSIMigration and CSIMigrationAzureDisk feature flags enabled and AzureDisk CSI plugin installed and configured on all nodes in the cluster.
  • CSIMigrationAzureFile: Enables shims and translation logic to route volume operations from the Azure-File in-tree plugin to AzureFile CSI plugin. Supports falling back to in-tree AzureFile plugin if a node does not have AzureFile CSI plugin installed and configured. Requires CSIMigration feature flag enabled.
  • CSIMigrationAzureFileComplete: Stops registering the Azure-File in-tree plugin in kubelet and volume controllers and enables shims and translation logic to route volume operations from the Azure-File in-tree plugin to AzureFile CSI plugin. Requires CSIMigration and CSIMigrationAzureFile feature flags enabled and AzureFile CSI plugin installed and configured on all nodes in the cluster.
  • CSIMigrationGCE: Enables shims and translation logic to route volume operations from the GCE-PD in-tree plugin to PD CSI plugin. Supports falling back to in-tree GCE plugin if a node does not have PD CSI plugin installed and configured. Requires CSIMigration feature flag enabled.
  • CSIMigrationGCEComplete: Stops registering the GCE-PD in-tree plugin in kubelet and volume controllers and enables shims and translation logic to route volume operations from the GCE-PD in-tree plugin to PD CSI plugin. Requires CSIMigration and CSIMigrationGCE feature flags enabled and PD CSI plugin installed and configured on all nodes in the cluster.
  • CSIMigrationOpenStack: Enables shims and translation logic to route volume operations from the Cinder in-tree plugin to Cinder CSI plugin. Supports falling back to in-tree Cinder plugin if a node does not have Cinder CSI plugin installed and configured. Requires CSIMigration feature flag enabled.
  • CSIMigrationOpenStackComplete: Stops registering the Cinder in-tree plugin in kubelet and volume controllers and enables shims and translation logic to route volume operations from the Cinder in-tree plugin to Cinder CSI plugin. Requires CSIMigration and CSIMigrationOpenStack feature flags enabled and Cinder CSI plugin installed and configured on all nodes in the cluster.
  • CSIMigrationvSphere: Enables shims and translation logic to route volume operations from the vSphere in-tree plugin to vSphere CSI plugin. Supports falling back to in-tree vSphere plugin if a node does not have vSphere CSI plugin installed and configured. Requires CSIMigration feature flag enabled.
  • CSIMigrationvSphereComplete: Stops registering the vSphere in-tree plugin in kubelet and volume controllers and enables shims and translation logic to route volume operations from the vSphere in-tree plugin to vSphere CSI plugin. Requires CSIMigration and CSIMigrationvSphere feature flags enabled and vSphere CSI plugin installed and configured on all nodes in the cluster.
  • CSINodeInfo: Enable all logic related to the CSINodeInfo API object in csi.storage.k8s.io.
  • CSIPersistentVolume: Enable discovering and mounting volumes provisioned through a CSI (Container Storage Interface) compatible volume plugin.
  • CSIServiceAccountToken: Enable CSI drivers to receive the pods' service account token that they mount volumes for. See Token Requests.
  • CSIStorageCapacity: Enables CSI drivers to publish storage capacity information and the Kubernetes scheduler to use that information when scheduling pods. See Storage Capacity. Check the csi volume type documentation for more details.
  • CSIVolumeFSGroupPolicy: Allows CSIDrivers to use the fsGroupPolicy field. This field controls whether volumes created by a CSIDriver support volume ownership and permission modifications when these volumes are mounted.
  • ConfigurableFSGroupPolicy: Allows user to configure volume permission change policy for fsGroups when mounting a volume in a Pod. See Configure volume permission and ownership change policy for Pods for more details.
  • CronJobControllerV2: Use an alternative implementation of the CronJob controller. Otherwise, version 1 of the same controller is selected. The version 2 controller provides experimental performance improvements.
  • CustomCPUCFSQuotaPeriod: Enable nodes to change cpuCFSQuotaPeriod in kubelet config.
  • CustomPodDNS: Enable customizing the DNS settings for a Pod using its dnsConfig property. Check Pod's DNS Config for more details.
  • CustomResourceDefaulting: Enable CRD support for default values in OpenAPI v3 validation schemas.
  • CustomResourcePublishOpenAPI: Enables publishing of CRD OpenAPI specs.
  • CustomResourceSubresources: Enable /status and /scale subresources on resources created from CustomResourceDefinition.
  • CustomResourceValidation: Enable schema based validation on resources created from CustomResourceDefinition.
  • CustomResourceWebhookConversion: Enable webhook-based conversion on resources created from CustomResourceDefinition.
  • DefaultPodTopologySpread: Enables the use of PodTopologySpread scheduling plugin to do default spreading.
  • DevicePlugins: Enable the device-plugins based resource provisioning on nodes.
  • DisableAcceleratorUsageMetrics: Disable accelerator metrics collected by the kubelet.
  • DownwardAPIHugePages: Enables usage of hugepages in downward API.
  • DryRun: Enable server-side dry run requests so that validation, merging, and mutation can be tested without committing.
  • DynamicAuditing(deprecated): Used to enable dynamic auditing before v1.19.
  • DynamicKubeletConfig: Enable the dynamic configuration of kubelet. See Reconfigure kubelet.
  • DynamicProvisioningScheduling: Extend the default scheduler to be aware of volume topology and handle PV provisioning. This feature is superseded by the VolumeScheduling feature completely in v1.12.
  • DynamicVolumeProvisioning(deprecated): Enable the dynamic provisioning of persistent volumes to Pods.
  • EfficientWatchResumption: Allows for storage-originated bookmark (progress notify) events to be delivered to the users. This is only applied to watch operations.
  • EnableAggregatedDiscoveryTimeout (deprecated): Enable the five second timeout on aggregated discovery calls.
  • EnableEquivalenceClassCache: Enable the scheduler to cache equivalence of nodes when scheduling Pods.
  • EndpointSlice: Enables EndpointSlices for more scalable and extensible network endpoints. See Enabling EndpointSlices.
  • EndpointSliceNodeName: Enables EndpointSlice nodeName field.
  • EndpointSliceProxying: When enabled, kube-proxy running on Linux will use EndpointSlices as the primary data source instead of Endpoints, enabling scalability and performance improvements. See Enabling Endpoint Slices.
  • EndpointSliceTerminatingCondition: Enables EndpointSlice terminating and serving condition fields.
  • EphemeralContainers: Enable the ability to add ephemeral containers to running pods.
  • EvenPodsSpread: Enable pods to be scheduled evenly across topology domains. See Pod Topology Spread Constraints.
  • ExecProbeTimeout: Ensure kubelet respects exec probe timeouts. This feature gate exists in case any of your existing workloads depend on a now-corrected fault where Kubernetes ignored exec probe timeouts. See readiness probes.
  • ExpandCSIVolumes: Enable the expanding of CSI volumes.
  • ExpandInUsePersistentVolumes: Enable expanding in-use PVCs. See Resizing an in-use PersistentVolumeClaim.
  • ExpandPersistentVolumes: Enable the expanding of persistent volumes. See Expanding Persistent Volumes Claims.
  • ExperimentalCriticalPodAnnotation: Enable annotating specific pods as critical so that their scheduling is guaranteed. This feature is deprecated by Pod Priority and Preemption as of v1.13.
  • ExperimentalHostUserNamespaceDefaulting: Enabling the defaulting user namespace to host. This is for containers that are using other host namespaces, host mounts, or containers that are privileged or using specific non-namespaced capabilities (e.g. MKNODE, SYS_MODULE etc.). This should only be enabled if user namespace remapping is enabled in the Docker daemon.
  • GCERegionalPersistentDisk: Enable the regional PD feature on GCE.
  • GenericEphemeralVolume: Enables ephemeral, inline volumes that support all features of normal volumes (can be provided by third-party storage vendors, storage capacity tracking, restore from snapshot, etc.). See Ephemeral Volumes.
  • GracefulNodeShutdown: Enables support for graceful shutdown in kubelet. During a system shutdown, kubelet will attempt to detect the shutdown event and gracefully terminate pods running on the node. See Graceful Node Shutdown for more details.
  • HPAContainerMetrics: Enable the HorizontalPodAutoscaler to scale based on metrics from individual containers in target pods.
  • HPAScaleToZero: Enables setting minReplicas to 0 for HorizontalPodAutoscaler resources when using custom or external metrics.
  • HugePages: Enable the allocation and consumption of pre-allocated huge pages.
  • HugePageStorageMediumSize: Enable support for multiple sizes pre-allocated huge pages.
  • HyperVContainer: Enable Hyper-V isolation for Windows containers.
  • IPv6DualStack: Enable dual stack support for IPv6.
  • ImmutableEphemeralVolumes: Allows for marking individual Secrets and ConfigMaps as immutable for better safety and performance.
  • KubeletConfigFile (deprecated): Enable loading kubelet configuration from a file specified using a config file. See setting kubelet parameters via a config file for more details.
  • KubeletCredentialProviders: Enable kubelet exec credential providers for image pull credentials.
  • KubeletPluginsWatcher: Enable probe-based plugin watcher utility to enable kubelet to discover plugins such as CSI volume drivers.
  • KubeletPodResources: Enable the kubelet's pod resources gRPC endpoint. See Support Device Monitoring for more details.
  • LegacyNodeRoleBehavior: When disabled, legacy behavior in service load balancers and node disruption will ignore the node-role.kubernetes.io/master label in favor of the feature-specific labels provided by NodeDisruptionExclusion and ServiceNodeExclusion.
  • LocalStorageCapacityIsolation: Enable the consumption of local ephemeral storage and also the sizeLimit property of an emptyDir volume.
  • LocalStorageCapacityIsolationFSQuotaMonitoring: When LocalStorageCapacityIsolation is enabled for local ephemeral storage and the backing filesystem for emptyDir volumes supports project quotas and they are enabled, use project quotas to monitor emptyDir volume storage consumption rather than filesystem walk for better performance and accuracy.
  • MixedProtocolLBService: Enable using different protocols in the same LoadBalancer type Service instance.
  • MountContainers (deprecated): Enable using utility containers on host as the volume mounter.
  • MountPropagation: Enable sharing volume mounted by one container to other containers or pods. For more details, please see mount propagation.
  • NodeDisruptionExclusion: Enable use of the Node label node.kubernetes.io/exclude-disruption which prevents nodes from being evacuated during zone failures.
  • NodeLease: Enable the new Lease API to report node heartbeats, which could be used as a node health signal.
  • NonPreemptingPriority: Enable preemptionPolicy field for PriorityClass and Pod.
  • PVCProtection: Enable the prevention of a PersistentVolumeClaim (PVC) from being deleted when it is still used by any Pod.
  • PersistentLocalVolumes: Enable the usage of local volume type in Pods. Pod affinity has to be specified if requesting a local volume.
  • PodDisruptionBudget: Enable the PodDisruptionBudget feature.
  • PodOverhead: Enable the PodOverhead feature to account for pod overheads.
  • PodPriority: Enable the descheduling and preemption of Pods based on their priorities.
  • PodReadinessGates: Enable the setting of PodReadinessGate field for extending Pod readiness evaluation. See Pod readiness gate for more details.
  • PodShareProcessNamespace: Enable the setting of shareProcessNamespace in a Pod for sharing a single process namespace between containers running in a pod. More details can be found in Share Process Namespace between Containers in a Pod.
  • ProcMountType: Enables control over the type proc mounts for containers by setting the procMount field of a SecurityContext.
  • QOSReserved: Allows resource reservations at the QoS level preventing pods at lower QoS levels from bursting into resources requested at higher QoS levels (memory only for now).
  • RemainingItemCount: Allow the API servers to show a count of remaining items in the response to a chunking list request.
  • RemoveSelfLink: Deprecates and removes selfLink from ObjectMeta and ListMeta.
  • ResourceLimitsPriorityFunction (deprecated): Enable a scheduler priority function that assigns a lowest possible score of 1 to a node that satisfies at least one of the input Pod's cpu and memory limits. The intent is to break ties between nodes with same scores.
  • ResourceQuotaScopeSelectors: Enable resource quota scope selectors.
  • RootCAConfigMap: Configure the kube-controller-manager to publish a ConfigMap named kube-root-ca.crt to every namespace. This ConfigMap contains a CA bundle used for verifying connections to the kube-apiserver. See Bound Service Account Tokens for more details.
  • RotateKubeletClientCertificate: Enable the rotation of the client TLS certificate on the kubelet. See kubelet configuration for more details.
  • RotateKubeletServerCertificate: Enable the rotation of the server TLS certificate on the kubelet. See kubelet configuration for more details.
  • RunAsGroup: Enable control over the primary group ID set on the init processes of containers.
  • RuntimeClass: Enable the RuntimeClass feature for selecting container runtime configurations.
  • ScheduleDaemonSetPods: Enable DaemonSet Pods to be scheduled by the default scheduler instead of the DaemonSet controller.
  • SCTPSupport: Enables the SCTP protocol value in Pod, Service, Endpoints, EndpointSlice, and NetworkPolicy definitions.
  • ServerSideApply: Enables the Sever Side Apply (SSA) feature on the API Server.
  • ServiceAccountIssuerDiscovery: Enable OIDC discovery endpoints (issuer and JWKS URLs) for the service account issuer in the API server. See Configure Service Accounts for Pods for more details.
  • ServiceAppProtocol: Enables the AppProtocol field on Services and Endpoints.
  • ServiceLBNodePortControl: Enables the spec.allocateLoadBalancerNodePorts field on Services.
  • ServiceLoadBalancerFinalizer: Enable finalizer protection for Service load balancers.
  • ServiceNodeExclusion: Enable the exclusion of nodes from load balancers created by a cloud provider. A node is eligible for exclusion if labelled with "node.kubernetes.io/exclude-from-external-load-balancers".
  • ServiceTopology: Enable service to route traffic based upon the Node topology of the cluster. See ServiceTopology for more details.
  • SetHostnameAsFQDN: Enable the ability of setting Fully Qualified Domain Name(FQDN) as the hostname of a pod. See Pod's setHostnameAsFQDN field.
  • SizeMemoryBackedVolumes: Enable kubelets to determine the size limit for memory-backed volumes (mainly emptyDir volumes).
  • StartupProbe: Enable the startup probe in the kubelet.
  • StorageObjectInUseProtection: Postpone the deletion of PersistentVolume or PersistentVolumeClaim objects if they are still being used.
  • StorageVersionAPI: Enable the storage version API.
  • StorageVersionHash: Allow API servers to expose the storage version hash in the discovery.
  • StreamingProxyRedirects: Instructs the API server to intercept (and follow) redirects from the backend (kubelet) for streaming requests. Examples of streaming requests include the exec, attach and port-forward requests.
  • SupportIPVSProxyMode: Enable providing in-cluster service load balancing using IPVS. See service proxies for more details.
  • SupportPodPidsLimit: Enable the support to limiting PIDs in Pods.
  • SupportNodePidsLimit: Enable the support to limiting PIDs on the Node. The parameter pid=<number> in the --system-reserved and --kube-reserved options can be specified to ensure that the specified number of process IDs will be reserved for the system as a whole and for Kubernetes system daemons respectively.
  • Sysctls: Enable support for namespaced kernel parameters (sysctls) that can be set for each pod. See sysctls for more details.
  • TTLAfterFinished: Allow a TTL controller to clean up resources after they finish execution.
  • TaintBasedEvictions: Enable evicting pods from nodes based on taints on Nodes and tolerations on Pods. See taints and tolerations for more details.
  • TaintNodesByCondition: Enable automatic tainting nodes based on node conditions.
  • TokenRequest: Enable the TokenRequest endpoint on service account resources.
  • TokenRequestProjection: Enable the injection of service account tokens into a Pod through a projected volume.
  • TopologyManager: Enable a mechanism to coordinate fine-grained hardware resource assignments for different components in Kubernetes. See Control Topology Management Policies on a node.
  • VolumePVCDataSource: Enable support for specifying an existing PVC as a DataSource.
  • VolumeScheduling: Enable volume topology aware scheduling and make the PersistentVolumeClaim (PVC) binding aware of scheduling decisions. It also enables the usage of local volume type when used together with the PersistentLocalVolumes feature gate.
  • VolumeSnapshotDataSource: Enable volume snapshot data source support.
  • VolumeSubpathEnvExpansion: Enable subPathExpr field for expanding environment variables into a subPath.
  • WarningHeaders: Allow sending warning headers in API responses.
  • WatchBookmark: Enable support for watch bookmark events.
  • WinDSR: Allows kube-proxy to create DSR loadbalancers for Windows.
  • WinOverlay: Allows kube-proxy to run in overlay mode for Windows.
  • WindowsGMSA: Enables passing of GMSA credential specs from pods to container runtimes.
  • WindowsRunAsUserName : Enable support for running applications in Windows containers with as a non-default user. See Configuring RunAsUserName for more details.
  • WindowsEndpointSliceProxying: When enabled, kube-proxy running on Windows will use EndpointSlices as the primary data source instead of Endpoints, enabling scalability and performance improvements. See Enabling Endpoint Slices.

What's next

  • The deprecation policy for Kubernetes explains the project's approach to removing features and components.
Last modified January 31, 2021 at 4:56 PM PST: [zh] Sync changes to feature-gates (816725246d)