Day 06/40 Days of K8s: KIND Multi-Node cluster Setup locally.

Before diving into managed Kubernetes services on the cloud, it's crucial to set up and manage own cluster locally. This hands-on approach allows us to better understand all components, especially the control plane, and gain valuable experience in troubleshooting and debugging.

KIND (Kubernetes In Docker)creates all nodes as docker container, light-weight to run and multi-node Kubernetes environment for local development and testing.

Prerequisites:

1. Install kubectl

2. Install KIND

Creating a Single-Node Cluster:

1. Create the cluster:

    kind create cluster --image kindest/node:v1.29.4@sha256:3abb816a5b1061fb15c6e9e60856ec40d56b7b52bcea5f5f1350bc6e2320b6f8 --name cluster-1
   

2. Get cluster info:

    kubectl cluster-info --context kind-cluster-1
   

3. Check current context:

    kubectl config current-context
   

Note: All requests from client go to the API server, which retrieves data from etcd and returns the output.

Creating a Multi-Node Cluster (1 Control Plane, 2 Workers)

1. Create a config.yaml file defining the cluster structure

2. Config file contents:

    # three node (two workers) cluster config
    kind: Cluster
    apiVersion: kind.x-k8s.io/v1alpha4
    nodes:
    - role: control-plane
    - role: worker
    - role: worker
   

3. Create the cluster using the config file:

    kind create cluster --image kindest/node:v1.29.4@sha256:3abb816a5b1061fb15c6e9e60856ec40d56b7b52bcea5f5f1350bc6e2320b6f8 --name kind-cluster-2 --config config.yaml
   

4. Workers are automatically joined to the control plane.

Managing Cluster Contexts

• View current context:

    kubectl config current-context
  

• Switch context:

    kubectl config use-context kind-cluster-1
  

• List all contexts:

    kubectl config get-contexts
  

  Kubectl config set-context: It is used to create a new context or modify an existing one in the context-list.
  kubectl config use-context: It is used for switching to an already existing context.

This provides a clear overview of the process, separating the single-node and multi-node cluster setups, and including managing cluster contexts.

🛑 IMPORTANT: It's critical to ensure you're working on the correct cluster context at all times. Operating on the wrong context can lead to unintended changes in the wrong cluster.

#Kubernetes #KIND #OneNodeCluster #MultiNodeCluster #40DaysofKubernetes #CKASeries