Taints and tolerations in Kubernetes - Mini Project: Build & Apply

Kubernetes Taints and Tolerations Setup

📖 Scenario: You are managing a Kubernetes cluster where certain nodes should only run special workloads. To control this, you will use taints on nodes and tolerations on pods.This helps keep normal workloads off special nodes, like reserving some nodes for high-memory jobs.

🎯 Goal: Learn how to add a taint to a Kubernetes node and create a pod that tolerates that taint so it can be scheduled on that node.

📋 What You'll Learn

Add a taint to a node named special-node with key special, value true, and effect NoSchedule

Create a pod manifest named toleration-pod.yaml that tolerates the taint with the exact key, value, and effect

Verify the pod can be scheduled on the tainted node

💡 Why This Matters

🌍 Real World

Taints and tolerations help Kubernetes cluster admins control which nodes run which workloads, improving resource management and stability.

💼 Career

Understanding taints and tolerations is essential for Kubernetes operators and DevOps engineers to manage workload placement and cluster reliability.

1

Add a taint to the node

Use the kubectl taint nodes command to add a taint with key special, value true, and effect NoSchedule to the node named special-node.

Kubernetes

# Your code here

Need a hint?

This command adds a taint so pods without matching tolerations won't be scheduled on special-node.

2

Create a pod manifest with tolerations

Create a YAML file named toleration-pod.yaml that defines a pod with a toleration for the taint key special, value true, and effect NoSchedule. The pod should run the nginx container.

Kubernetes

# Write the pod manifest YAML below
# Your code here

Need a hint?

The tolerations section must exactly match the taint's key, value, and effect.

3

Apply the pod manifest

Use kubectl apply -f toleration-pod.yaml to create the pod with the toleration.

Kubernetes

# Apply the pod manifest below
# Your code here

Need a hint?

This command creates the pod that can run on the tainted node.

4

Check pod scheduling on the tainted node

Run kubectl get pods -o wide and verify that the pod named toleration-pod is scheduled on the node special-node. Write the exact command and then the expected output line for the pod.

Kubernetes

# Run the command to check pods and write the expected output line below
# Your code here

Need a hint?

The pod should be listed as running on special-node.