Kubernetes Setup On Ubuntu 22.04

Install Pod Network Plugin

Install a Pod network plugin like Flannel to enable communication between Kubernetes pods.

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🌐 Step 4: Install a Pod Network Plugin

After the Kubernetes control plane is initialized, the cluster nodes can’t communicate until a Pod network plugin is installed.


Why is this necessary?

Kubernetes requires a network plugin to allow Pods running on different nodes to communicate with each other. Without it, nodes will stay in NotReady status.


🔧 Installing Flannel (Recommended)

Flannel is a simple and widely used network plugin for Kubernetes.

Run this command on the control plane node (cp-node-1):

bash

🖥️ Verify the Pod Network Plugin

Check if the kube-flannel pods are running:

bash

Wait for all Flannel pods to be in Running status.


✅ Check Node Status

After Flannel is running, your nodes should transition to Ready state.

Verify nodes:

bash

Troubleshooting

  • If nodes remain NotReady for a long time:
    • Check the Flannel pod logs:
bash
  • Verify firewall rules or network policies aren’t blocking traffic.

⏭ Next Steps

Your Kubernetes cluster is now operational with a network plugin installed.

Next, you can:

  • Deploy your first workloads.
  • Set up cluster add-ons (metrics-server, dashboard).
  • Configure storage classes for persistent storage.

👉 Go to Page 5: Deploy Your First Kubernetes Workload →