Kubernetes architecture (control plane and nodes) - Mini Project: Build & Apply

Kubernetes Architecture: Control Plane and Nodes

📖 Scenario: You are learning how Kubernetes manages containerized applications. Kubernetes uses a control plane to manage the cluster and nodes to run your applications.Imagine you want to understand the basic components of Kubernetes architecture by creating a simple representation of the control plane and nodes using YAML files.

🎯 Goal: Build a simple Kubernetes cluster configuration with a control plane and two worker nodes using YAML manifests.

📋 What You'll Learn

Create a YAML manifest for the control plane with specific components

Add a YAML manifest for worker nodes with labels

Use selectors to identify nodes

Display the final YAML manifests

💡 Why This Matters

🌍 Real World

Kubernetes uses YAML manifests to define and manage cluster components and workloads. Understanding this helps you configure and troubleshoot clusters.

💼 Career

DevOps engineers and site reliability engineers often write and read Kubernetes manifests to deploy and maintain applications in production.

1

Create Control Plane YAML Manifest

Create a YAML manifest called control-plane.yaml that defines the control plane components with these exact keys and values: apiVersion: v1, kind: ControlPlane, metadata: with name: kubernetes-control-plane, and spec: with components: listing etcd, kube-apiserver, kube-controller-manager, and kube-scheduler.

Kubernetes

# Create control-plane.yaml manifest with specified keys and values
# Your code here

Need a hint?

Use YAML syntax with indentation. List the components under spec.components.

2

Create Worker Nodes YAML Manifest

Create a YAML manifest called worker-nodes.yaml that defines two worker nodes with these exact details: apiVersion: v1, kind: NodeList, items: containing two nodes each with metadata: including name as worker-node-1 and worker-node-2, and labels: with role: worker.

Kubernetes

apiVersion: v1
kind: ControlPlane
metadata:
  name: kubernetes-control-plane
spec:
  components:
    - etcd
    - kube-apiserver
    - kube-controller-manager
    - kube-scheduler

# Create worker-nodes.yaml manifest with two nodes and labels
# Your code here

Need a hint?

Use a list under items to define multiple nodes. Each node has metadata.name and metadata.labels.role.

3

Add Node Selector to Control Plane Spec

In the existing control-plane.yaml manifest, add a new key nodeSelector under spec with the exact value role: worker to specify that control plane components should run on worker nodes.

Kubernetes

apiVersion: v1
kind: ControlPlane
metadata:
  name: kubernetes-control-plane
spec:
  components:
    - etcd
    - kube-apiserver
    - kube-controller-manager
    - kube-scheduler
  # Add nodeSelector with role: worker below

---
apiVersion: v1
kind: NodeList
items:
  - metadata:
      name: worker-node-1
      labels:
        role: worker
  - metadata:
      name: worker-node-2
      labels:
        role: worker

Need a hint?

Indent nodeSelector under spec and set role: worker.

4

Display Final YAML Manifests

Print the full content of both control-plane.yaml and worker-nodes.yaml manifests exactly as created, separated by a line with three dashes ---.

Kubernetes

# Print the full YAML manifests below
# Your code here

Need a hint?

Use print() statements to output the YAML content exactly as created, including the separator line ---.