Kubernetes Nodes: A Kubernetes cluster consists of nodes (worker machines) where your applications run. In a cloud environment, these nodes are almost always VMs.
Container Runtime: Each node runs a container runtime (like Docker or containerd) which is responsible for running the actual containers. This runtime operates within the VM.
Control Plane: While the control plane (API server, scheduler, etc.) can run on VMs, it's also common to see managed Kubernetes services where the cloud provider handles the control plane infrastructure separately. However, the worker nodes (where your applications run) are still VMs.
Cloud Provider Integration: Cloud providers offer managed Kubernetes services (like GKE, EKS, AKS) that abstract away much of the VM management. However, under the hood, your workloads are still running on VMs provided by the cloud platform.
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A) While the control plane can run on VMs, it's not exclusive. More importantly, containerized applications do not run directly on physical servers in a typical cloud-based Kubernetes setup. They run inside containers, which run on VMs.
C) Persistent storage can use VMs for certain storage solutions, but it's not the primary use case for VMs in Kubernetes. The main purpose of VMs is to provide the compute resources (nodes) for running containers.
D) Kubernetes does not eliminate the need for VMs in cloud environments. While bare-metal Kubernetes deployments are possible, they are less common in cloud environments. Cloud providers leverage virtualization (VMs) to provide infrastructure as a service, which Kubernetes then utilizes.