Kubelet

The kubelet systemd process is the heavy lifter for changes and configuration on worker nodes. It accepts the API calls for Pod specifications (a PodSpec is a JSON or YAML file that describes a pod). It will work to configure the local node until the specification has been met.

Should a Pod require access to storage, Secrets or ConfigMaps, the kubelet will ensure access or creation. It also sends back status to the kube-apiserver for eventual persistence. ​

• Uses PodSpec

• Mounts volumes to Pod

• Downloads secrets

• Passes request to local container engine

• Reports status of Pods and node to cluster.

Kubelet calls other components such as the Topology Manager, which uses hints from other components to configure topology-aware resource NUMA assignments such as for CPU and hardware accelerators. As an alpha feature, it is not enabled by default.