What you’ll Learn

• Introduction to Kubernetes
• How to deploy a Kubernetes cluster with kind
• Learn basic kubectl commands

What You’ll Need

• Install kind
• Set up kubectl
• Make sure you have Docker set up
• Have fun!

Kubernetes, also known as K8s, is an open-source system for automating deployment, scaling and managing of containerized apps.

• Kubernetes is a virtualization layer of your servers that helps you deploy containers across a pool of computer resources.
• Kubernetes makes it easy to:
  • Deploy containers to shared resources.
  • Manage multiple replicas of your application onto a shared pool.
  • Scale up and scale down applications based on usage.

Now that we have an understanding what K8s let’s deploy our own cluster!

kind is a tool for running local Kubernetes clusters using Docker container “nodes.” kind was primarily designed for testing Kubernetes itself, but it may be used for local development or CI.

1. This sample cluster YAML file is used with kind to config and build our cluster.

• Save it to your local working directory

kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
nodes:
- role: control-plane
  extraPortMappings:
  - containerPort: 30201
    hostPort: 30201
    listenAddress: "0.0.0.0"

• The configuration file declaratively deploys Kubernetes within a container, and so we are defining:
  • kind: Cluster: This config merely specifies that we are configuring a kind cluster.
  • role: control-plane: This config defines the Kubernetes control plane. The control plane’s components make global decisions about the cluster (for example, scheduling) as well as detecting and responding to cluster events.
  • extraPortMappings: This config specifies the port mapping for our container so that we can reach our cluster.

2. It’s time to deploy our first cluster! Leveraging the kind-config.yaml to do so:
   • Open a new Terminal
   • Navigate to the location of kind-config.yaml using cd <directory> in your Terminal
   • Create the cluster by entering the following command in your Terminal

kind create cluster --name my-kubernetes-cluster --config kind-config.yaml

3. You now have a working Kubernetes cluster. Confirm that the my-kubernetes-cluster cluster was created, using your terminal execute:

kind get clusters

4. Configure kubectl so we can interact with it, in your terminal execute:

kubectl cluster-info --context kind-my-kubernetes-cluster

5. Let’s get some information about our cluster using kubectl, in your terminal execute:

kubectl config view --minify --flatten --context=kind-my-kubernetes-cluster

You’ve made it this far! now that we have a Kubernetes cluster! we need a way to interact with it the standard command line employed to communicate with it is Kubectl

In your terminal, let’s try some commonly used kubectl commands!

Cluster Management

• Display endpoint information regarding the services and controller in the cluster:

kubectl cluster-info

• Show the Kubernetes version functioning on the client and server:

kubectl version

• Get the configuration of the cluster:

kubectl config view

• Get a list of the available API resources:

kubectl api-resources

• List everything:

kubectl get all

Namespaces

In Kubernetes, namespaces provide a mechanism for isolating groups of resources within a single cluster.

• Create a namespace:

kubectl create namespace my-first-ns

• Get a list of all namespaces:

kubectl get namespaces

• Show the detailed condition of one or more namespaces:

kubectl describe namespace my-first-ns

• Delete a namespace:

kubectl delete namespace my-first-ns

ℹ️ For a complete list of kubectl commands and to learn more, check out this Cheat Sheet.

Congratulations! You’ve successfully completed this lab!

Learn More

• Cisco Learning Network DevNet Certifications Community
• DevNet Certification Training Videos
• DevNet Automation Bootcamp