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---
title: Feature Gates
weight: 10
notitle: true
---
## Feature Gates
This page contains an overview of the various feature gates an administrator
can specify on different Kubernetes components.
## Overview
Feature gates are a set of key=value pairs that describe alpha or experimental
features.
An administrator can use the `--feature-gates` command line flag on each component
to turn a feature on or off.
The following table is 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.
| Feature | Default | Stage | Since | Until |
|---------|---------|-------|-------|-------|
| `Accelerators` | `false` | Alpha | 1.6 | 1.10 |
| `AdvancedAuditing` | `false` | Alpha | 1.7 | 1.7 |
| `AdvancedAuditing` | `true` | Beta | 1.8 | |
| `AffinityInAnnotations` | `false` | Alpha | 1.6 | 1.7 |
| `AllowExtTrafficLocalEndpoints` | `false` | Beta | 1.4 | 1.6 |
| `AllowExtTrafficLocalEndpoints` | `true` | GA | 1.7 | |
| `APIListChunking` | `false` | Alpha | 1.8 | 1.8 |
| `APIListChunking` | `true` | Beta | 1.9 | |
| `APIResponseCompression` | `false` | Alpha | 1.7 | |
| `AppArmor` | `true` | Beta | 1.4 | |
| `AttachVolumeLimit` | `false` | Alpha | 1.11 | |
| `BlockVolume` | `false` | Alpha | 1.9 | |
| `CPUManager` | `false` | Alpha | 1.8 | 1.9 |
| `CPUManager` | `true` | Beta | 1.10 | |
| `CRIContainerLogRotation` | `false` | Alpha | 1.10 | 1.10 |
| `CRIContainerLogRotation` | `true` | Beta| 1.11 | |
| `CSIBlockVolume` | `false` | Alpha | 1.11 | 1.11 |
| `CSIPersistentVolume` | `false` | Alpha | 1.9 | 1.9 |
| `CSIPersistentVolume` | `true` | Beta | 1.10 | |
| `CustomPodDNS` | `false` | Alpha | 1.9 | 1.9 |
| `CustomPodDNS` | `true` | Beta| 1.10 | |
| `CustomResourceSubresources` | `false` | Alpha | 1.10 | |
| `CustomResourceValidation` | `false` | Alpha | 1.8 | 1.8 |
| `CustomResourceValidation` | `true` | Beta | 1.9 | |
| `DebugContainers` | `false` | Alpha | 1.10 | |
| `DevicePlugins` | `false` | Alpha | 1.8 | 1.9 |
| `DevicePlugins` | `true` | Beta | 1.10 | |
| `DynamicKubeletConfig` | `false` | Alpha | 1.4 | 1.10 |
| `DynamicKubeletConfig` | `true` | Beta | 1.11 | |
| `DynamicVolumeProvisioning` | `true` | Alpha | 1.3 | 1.7 |
| `DynamicVolumeProvisioning` | `true` | GA | 1.8 | |
| `EnableEquivalenceClassCache` | `false` | Alpha | 1.8 | |
| `ExpandPersistentVolumes` | `false` | Alpha | 1.8 | 1.10 |
| `ExpandPersistentVolumes` | `true` | Beta | 1.11 | |
| `ExperimentalCriticalPodAnnotation` | `false` | Alpha | 1.5 | |
| `ExperimentalHostUserNamespaceDefaulting` | `false` | Beta | 1.5 | |
| `GCERegionalPersistentDisk` | `true` | Beta | 1.10 | |
| `HugePages` | `false` | Alpha | 1.8 | 1.9 |
| `HugePages` | `true` | Beta| 1.10 | |
| `HyperVContainer` | `false` | Alpha | 1.10 | |
| `Initializers` | `false` | Alpha | 1.7 | |
| `KubeletConfigFile` | `false` | Alpha | 1.8 | 1.9 |
| `KubeletPluginsWatcher` | `false` | Alpha | 1.11 | |
| `LocalStorageCapacityIsolation` | `false` | Alpha | 1.7 | 1.9 |
| `LocalStorageCapacityIsolation` | `true` | Beta| 1.10 | |
| `MountContainers` | `false` | Alpha | 1.9 | |
| `MountPropagation` | `false` | Alpha | 1.8 | 1.9 |
| `MountPropagation` | `true` | Beta | 1.10 | |
| `PersistentLocalVolumes` | `false` | Alpha | 1.7 | 1.9 |
| `PersistentLocalVolumes` | `true` | Beta | 1.10 | |
| `PodPriority` | `false` | Alpha | 1.8 | |
| `PodReadinessGates` | `false` | Alpha | 1.11 | |
| `PodShareProcessNamespace` | `false` | Alpha | 1.10 | |
| `PVCProtection` | `false` | Alpha | 1.9 | 1.9 |
| `ReadOnlyAPIDataVolumes` | `true` | Deprecated | 1.10 | |
| `ResourceLimitsPriorityFunction` | `false` | Alpha | 1.9 | |
| `RotateKubeletClientCertificate` | `true` | Beta | 1.7 | |
| `RotateKubeletServerCertificate` | `false` | Alpha | 1.7 | |
| `RunAsGroup` | `false` | Alpha | 1.10 | |
| `ServiceNodeExclusion` | `false` | Alpha | 1.8 | |
| `StorageObjectInUseProtection` | `true` | Beta | 1.10 | 1.10 |
| `StorageObjectInUseProtection` | `true` | GA | 1.11 | |
| `StreamingProxyRedirects` | `true` | Beta | 1.5 | |
| `SupportIPVSProxyMode` | `false` | Alpha | 1.8 | 1.8 |
| `SupportIPVSProxyMode` | `false` | Beta | 1.9 | 1.9 |
| `SupportIPVSProxyMode` | `true` | Beta | 1.10 | 1.10 |
| `SupportIPVSProxyMode` | `true` | GA | 1.11 | |
| `SupportPodPidsLimit` | `false` | Alpha | 1.10 | |
| `Sysctls` | `true` | Beta | 1.11 | |
| `TaintBasedEvictions` | `false` | Alpha | 1.6 | |
| `TaintNodesByCondition` | `false` | Alpha | 1.8 | |
| `TokenRequest` | `false` | Alpha | 1.10 | |
| `TokenRequestProjection` | `false` | Alpha | 1.11 | |
| `VolumeScheduling` | `false` | Alpha | 1.9 | 1.9 |
| `VolumeScheduling` | `true` | Beta | 1.10 | |
| `VolumeSubpathEnvExpansion` | `false` | Alpha | 1.11 | |
| `ScheduleDaemonSetPods` | `false` | Alpha | 1.11 | |
## 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 >}}
**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.
{{< /note >}}
A *GA* feature is also referred to as a *stable* feature. It means:
* The corresponding feature gate is no longer needed.
* Stable versions of features will appear in released software for many subsequent versions.
### Feature Gates
Each feature gate is designed for enabling/disabling a specific feature:
- `Accelerators`: Enable Nvidia GPU support when using Docker
- `AdvancedAuditing`: Enable [advanced auditing](/docs/tasks/debug-application-cluster/audit/#advanced-audit)
- `AffinityInAnnotations`(*deprecated*): Enable setting [Pod affinity or anti-affinitys](/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity).
- `AllowExtTrafficLocalEndpoints`: Enable a service to route external requests to node local endpoints.
- `APIListChunking`: Enable the API clients to retrieve (`LIST` or `GET`) resources from API server in chunks.
- `APIResponseCompression`: Compress the API responses for `LIST` or `GET` requests.
- `AppArmor`: Enable AppArmor based mandatory access control on Linux nodes when using Docker.
See [AppArmor Tutorial](/docs/tutorials/clusters/apparmor/) 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](/docs/concepts/storage/storage-limits/#dynamic-volume-limits) for more details.
- `BlockVolume`: Enable the definition and consumption of raw block devices in Pods.
See [Raw Block Volume Support](/docs/concepts/storage/persistent-volumes/#raw-block-volume-support)
for more details.
- `CPUManager`: Enable container level CPU affinity support, see [CPU Management Policies](/docs/tasks/administer-cluster/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](/docs/concepts/storage/volumes/#csi-raw-block-volume-support) documentation for more details.
- `CSIPersistentVolume`: Enable discovering and mounting volumes provisioned through a
[CSI (Container Storage Interface)](https://github.com/kubernetes/community/blob/master/contributors/design-proposals/storage/container-storage-interface.md)
compatible volume plugin.
Check the [`csi` volume type](/docs/concepts/storage/volumes/#csi) documentation for more details.
- `CustomPodDNS`: Enable customizing the DNS settings for a Pod using its `dnsConfig` property.
Check [Pod's DNS Config](/docs/concepts/services-networking/dns-pod-service/#pods-dns-config)
for more details.
- `CustomResourceSubresources`: Enable `/status` and `/scale` subresources
on resources created from [CustomResourceDefinition](/docs/concepts/api-extension/custom-resources/).
- `CustomResourceValidation`: Enable schema based validation on resources created from
[CustomResourceDefinition](/docs/concepts/api-extension/custom-resources/).
- `DebugContainers`: Enable running a "debugging" container in a Pod's namespace to
troubleshoot a running Pod.
- `DevicePlugins`: Enable the [device-plugins](/docs/concepts/cluster-administration/device-plugins/)
based resource provisioning on nodes.
- `DynamicKubeletConfig`: Enable the dynamic configuration of kubelet. See [Reconfigure kubelet](/docs/tasks/administer-cluster/reconfigure-kubelet/).
- `DynamicVolumeProvisioning`(*deprecated*): Enable the [dynamic provisioning](/docs/concepts/storage/dynamic-provisioning/) of persistent volumes to Pods.
- `EnableEquivalenceClassCache`: Enable the scheduler to cache equivalence of nodes when scheduling Pods.
- `ExpandPersistentVolumes`: Enable the expanding of persistent volumes. See [Expanding Persistent Volumes Claims](/docs/concepts/storage/persistent-volumes/#expanding-persistent-volumes-claims).
- `ExperimentalCriticalPodAnnotation`: Enable annotating specific pods as *critical* so that their [scheduling is guaranteed](/docs/tasks/administer-cluster/guaranteed-scheduling-critical-addon-pods/).
- `ExperimentalHostUserNamespaceDefaultingGate`: 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.
- `HugePages`: Enable the allocation and consumption of pre-allocated [huge pages](/docs/tasks/manage-hugepages/scheduling-hugepages/).
- `HyperVContainer`: Enable [Hyper-V isolation](https://docs.microsoft.com/en-us/virtualization/windowscontainers/manage-containers/hyperv-container) for Windows containers.
- `Intializers`: Enable the [dynamic admission control](/docs/admin/extensible-admission-controllers/)
as an extension to the built-in [admission controllers](/docs/admin/admission-controllers/).
When the `Initializers` admission controller is enabled, this feature is automatically enabled.
- `KubeletConfigFile`: Enable loading kubelet configuration from a file specified using a config file.
See [setting kubelet parameters via a config file](/docs/tasks/administer-cluster/kubelet-config-file/) for more details.
- `KubletPluginsWatcher`: Enable probe-based plugin watcher utility to enable kubelet
to discover plugins such as [CSI volume drivers](/docs/concepts/storage/volumes/#csi).
- `LocalStorageCapacityIsolation`: Enable the consumption of [local ephemeral storage](/docs/concepts/configuration/manage-compute-resources-container/) and also the `sizeLimit` property of an [emptyDir volume](/docs/concepts/storage/volumes/#emptydir).
- `MountContainers`: 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](/docs/concepts/storage/volumes/#mount-propagation).
- `PersistentLocalVolumes`: Enable the usage of `local` volume type in Pods.
Pod affinity has to be specified if requesting a `local` volume.
- `PodPriority`: Enable the descheduling and preemption of Pods based on their [priorities](/docs/concepts/configuration/pod-priority-preemption/).
- `PodReadinessGates`: Enable the setting of `PodReadinessGate` field for extending
Pod readiness evaluation.
For more details, please see [Pod readiness gate](/docs/concepts/workloads/pods/pod-lifecycle/#pod-readiness-gate).
- `PVCProtection`: Enable the prevention of a PersistentVolumeClaim (PVC) from
being deleted when it is still used by any Pod.
More details can be found [here](/docs/tasks/administer-cluster/pvc-protection/).
- `ReadOnlyAPIDataVolumes`: Set Secret, ConfigMap, DownwardAPI and projected volumes to be mounted in read-only mode.
This gate exists only for backward compatibility. It will be removed in 1.11 release.
- `ResourceLimitsPriorityFunction`: 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.
- `RotateKubeletClientCertificate`: Enable the rotation of the client TLS certificate on the kubelet.
See [kubelet configuration](/docs/reference/command-line-tools-reference/kubelet-tls-bootstrapping/#kubelet-configuration) for more details.
- `RotateKubeletServerCertificate`: Enable the rotation of the server TLS certificate on the kubelet.
See [kubelet configuration](/docs/reference/command-line-tools-reference/kubelet-tls-bootstrapping/#kubelet-configuration) for more details.
- `RunAsGroup`: Enable control over the primary group ID set on the init processes of containers.
- `ScheduleDaemonSetPods`: Enable DaemonSet Pods to be scheduled by the default scheduler instead of the DaemonSet controller.
- `ServiceNodeExclusion`: Enable the exclusion of nodes from load balancers created by a cloud provider.
A node is eligible for exclusion if annotated with "`alpha.service-controller.kubernetes.io/exclude-balancer`" key.
- `StorageObjectInUseProtection`: Postpone the deletion of PersistentVolume or
PersistentVolumeClaim objects if they are still being used.
- `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](/docs/concepts/services-networking/service/#virtual-ips-and-service-proxies) for more details.
- `SupportPodPidsLimit`: Enable the support to limiting PIDs in Pods.
- `Sysctls`: Enable support for namespaced kernel parameters (sysctls) that can be set for each pod.
See [sysctls](/docs/tasks/administer-cluster/sysctl-cluster/) for more details.
- `TaintBasedEvictions`: Enable evicting pods from nodes based on taints on nodes and tolerations on Pods.
See [taints and tolerations](/docs/concepts/configuration/taint-and-toleration/) for more details.
- `TaintNodesByCondition`: Enable automatic tainting nodes based on [node conditions](/docs/concepts/architecture/nodes/#condition).
- `TokenRequest`: Enable the `TokenRequest` endpoint on service account resources.
- `TokenRequestProjection`: Enable the injection of service account tokens into
a Pod through the [`projected` volume](/docs/concepts/storage/volumes/#projected).
- `VolumeScheduling`: Enable volume topology aware scheduling and make the
PersistentVolumeClaim (PVC) binding aware of scheduling decisions. It also
enables the usage of [`local`](/docs/concepts/storage/volumes/#local) volume
type when used together with the `PersistentLocalVolumes` feature gate.
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