Creating Highly Available Kubernetes Clusters Without a Cloud Provider

In this solution, we will create a highly available Kubernetes cluster without using a cloud provider. We will use Pulumi, an infrastructure as code tool, to define and deploy our Kubernetes cluster. The key services involved in this solution include Kubernetes for container orchestration, Pulumi for infrastructure management, and a set of virtual machines to host the Kubernetes nodes.

Introduction

In this guide, we will create a highly available Kubernetes cluster using Pulumi and TypeScript. This solution does not rely on any cloud provider, making it suitable for on-premises or self-hosted environments. We will use Pulumi to define and manage the infrastructure, and Kubernetes to orchestrate our containerized applications. The key services involved in this solution are Kubernetes, Pulumi, and virtual machines.

Step by Step Explanation

Step 1: Install Pulumi and Dependencies

First, ensure that you have Pulumi installed on your machine. You will also need Node.js and npm to manage the TypeScript dependencies.

Step 2: Create a New Pulumi Project

Create a new Pulumi project by running pulumi new typescript in your terminal. This will set up a new Pulumi project with the necessary configuration files.

Step 3: Define the Virtual Machines

Define the virtual machines that will host the Kubernetes nodes. You can use any virtualization platform, such as VirtualBox, VMware, or KVM. In this example, we will use a generic approach to define the VMs.

Step 4: Install and Configure Kubernetes

Install Kubernetes on the virtual machines and configure them to form a highly available cluster. This involves setting up the control plane and worker nodes, as well as configuring networking and storage.

Step 5: Define Kubernetes Resources in Pulumi

Use Pulumi to define the Kubernetes resources, such as namespaces, deployments, and services. This will allow you to manage your Kubernetes cluster using Pulumi’s infrastructure as code approach.

Step 6: Deploy the Kubernetes Cluster

Deploy the Kubernetes cluster by running pulumi up in your terminal. This will create the virtual machines, install Kubernetes, and configure the cluster according to your Pulumi code.

Key Points

• Pulumi allows you to define and manage infrastructure as code, making it easier to create and maintain complex environments.
• Kubernetes provides a powerful platform for orchestrating containerized applications, ensuring high availability and scalability.
• By using virtual machines, you can create a self-hosted Kubernetes cluster without relying on a cloud provider.
• This solution is suitable for on-premises environments or scenarios where cloud provider services are not available or desired.

Conclusion

In this guide, we have demonstrated how to create a highly available Kubernetes cluster without using a cloud provider. By leveraging Pulumi and TypeScript, we can define and manage our infrastructure as code, ensuring a consistent and repeatable deployment process. This solution is ideal for on-premises or self-hosted environments, providing a robust and scalable platform for running containerized applications.

Full Code Example

import * as pulumi from "@pulumi/pulumi";
import * as k8s from "@pulumi/kubernetes";
import * as command from "@pulumi/command";

const config = new pulumi.Config();
const nodeCount = config.getNumber("nodeCount") || 3;
const nodeSize = config.get("nodeSize") || "Standard_D2_v2";
const kubernetesVersion = config.get("kubernetesVersion") || "1.21.0";

// Define the virtual machines for the Kubernetes nodes
const nodes = [];
for (let i = 0; i < nodeCount; i++) {
    const node = new command.remote.CopyFile(`node-${i}`, {
        connection: {
            host: `192.168.1.${10 + i}`,
            user: "root",
            privateKey: "<private-key>"
        },
        localPath: "./install-k8s.sh",
        remotePath: "/root/install-k8s.sh"
    });
    nodes.push(node);
}

// Install Kubernetes on the nodes
const installK8s = nodes.map((node, i) => new command.remote.Command(`install-k8s-${i}`, {
    connection: {
        host: `192.168.1.${10 + i}`,
        user: "root",
        privateKey: "<private-key>"
    },
    create: "sh /root/install-k8s.sh"
}));

// Define the Kubernetes cluster
const cluster = new k8s.core.v1.Namespace("k8s-cluster", {
    metadata: { name: "k8s-cluster" }
});

// Define a Kubernetes Deployment
const appLabels = { app: "nginx" };
const deployment = new k8s.apps.v1.Deployment("nginx-deployment", {
    metadata: { namespace: cluster.metadata.name },
    spec: {
        selector: { matchLabels: appLabels },
        replicas: 3,
        template: {
            metadata: { labels: appLabels },
            spec: {
                containers: [{
                    name: "nginx",
                    image: "nginx:1.14.2",
                    ports: [{ containerPort: 80 }]
                }]
            }
        }
    }
});

// Define a Kubernetes Service
const service = new k8s.core.v1.Service("nginx-service", {
    metadata: { namespace: cluster.metadata.name },
    spec: {
        selector: appLabels,
        ports: [{ port: 80, targetPort: 80 }],
        type: "LoadBalancer"
    }
});

export const kubeconfig = pulumi.secret("<kubeconfig>");
export const clusterEndpoint = service.status.loadBalancer.ingress[0].hostname;