Feature Gates (add-on) extend the functionality of Kubernetes components, in this case provide additional capabilities for the kube-apiserver component.
Each add-on has a specific stage depending on the Kubernetes version:
- Alpha — disabled by default, can be enabled;
- Beta — enabled by default, cannot be disabled due to the policy of maintaining cluster stability;
- GA (General Availability) — added to the kube-apiserver core, always enabled by default, you cannot disable it.
To enable Feature Gates, you must list the names of the required add-ons when creating or updating a cluster. After that, kube-apiserver will be started or restarted with the
--feature-gates=... option and the specified add-ons.
Please note that when passing an add-on that is not available for the current Kubernetes version, a corresponding error will be returned.
To get information about the available controllers for each of the available Kubernetes versions, use an API request.