KubeletConfiguration

KubeletConfiguration is a Kubernetes API object that configures the kubelet, the node agent responsible for starting and supervising containers on a node. It is defined in the kubelet.config.k8s.io API group and version (for example apiVersion: kubelet.config.k8s.io/v1beta1; kind: KubeletConfiguration). Administrators typically supply it to the kubelet via the --config flag pointing to a YAML or JSON file on the node, replacing long command-line flag usage with a single configuration file.

The configuration file exposes many knobs that govern the kubelet's runtime behavior, such as resource management (eviction thresholds, image garbage collection), container runtime integration, logging, health checks, and networking-related settings. The fields are versioned and optional, with validation performed at load time; unknown fields can cause an error depending on the version and strictness of validation.

In addition to static files, Kubernetes supports dynamic kubelet configuration, where the kubelet fetches its KubeletConfiguration from the API server using a ConfigMap (usually in the kube-system namespace) and reloads as changes are applied, subject to version compatibility and feature gate availability.

This object is a key part of cluster automation and node lifecycle management, and it is used in concert with other standard kubelet flags and Kubernetes components. For current details, consult the Kubernetes API reference for the specific version in use.