Which component on a Kubernetes node directly runs containers?

Which component on a Kubernetes node directly runs containers?

• A. Kubelet
• B. API Server
• C. Kubernetes Scheduler
• D. Container Runtime

Answer: (D)

On a Kubernetes node, the actual container execution is handled by the container runtime. This software (such as containerd, CRI-O, or Docker in older setups) is what creates, starts, stops, and manages the life cycle of the container processes, including setting up namespaces, cgroups, networking, and mounting volumes. The kubelet on the node communicates with the runtime through the Container Runtime Interface (CRI) to launch and manage the containers that back each Pod. The API server and scheduler belong to the control plane and orchestrate across the cluster—they don’t run containers on the node themselves.

On a Kubernetes node, the actual container execution is handled by the container runtime. This software (such as containerd, CRI-O, or Docker in older setups) is what creates, starts, stops, and manages the life cycle of the container processes, including setting up namespaces, cgroups, networking, and mounting volumes. The kubelet on the node communicates with the runtime through the Container Runtime Interface (CRI) to launch and manage the containers that back each Pod. The API server and scheduler belong to the control plane and orchestrate across the cluster—they don’t run containers on the node themselves.