Deploying a Dockerized Node.js Application on Kubernetes 🚀

After containerizing an application with Docker, the next logical step is deploying it on Kubernetes. Kubernetes helps automate application deployment, scaling, networking, and management of containerized workloads. Instead of manually running containers, Kubernetes ensures your application remains available and can easily scale when needed. In this guide, we'll deploy a Docker image of a Node.js application on Kubernetes using a Deployment and a Service. Prerequisites Before starting, make sure you have: Docker installed Kubernetes cluster running (Docker Desktop Kubernetes, Minikube, Kind, EKS, etc.) kubectl configured A Docker image pushed to Docker Hub In my case, the image was: madhavnaks/node-app:latest Why Kubernetes? Running a container using Docker is straightforward: docker run -p 3000:3000 madhavnaks/node-app:latest However, in production environments we need much more than simply running a container. Kubernetes provides: High availability Self-healing containers Load balancing Service discovery Horizontal scaling Rolling updates This makes it the industry standard for container orchestration. Understanding the Kubernetes Architecture for This Deployment For this deployment, we'll use two Kubernetes resources: Deployment A Deployment is responsible for: Creating Pods Maintaining desired replica count Recreating failed Pods automatically Managing updates and rollbacks Service A Service provides a stable network endpoint for Pods. Since Pod IPs change frequently, Services allow applications and users to communicate reliably with Pods. Deployment and Service Manifest Create a file named: app.yaml Add the following configuration: apiVersion : apps/v1 kind : Deployment metadata : name : node-app spec : replicas : 2 selector : matchLabels : app : node-app template : metadata : labels : app : node-app spec : containers : - name : node-app image : madhavnaks/node-app:latest ports : - containerPort : 3000 --- apiVersion : v1 kind : Service metadata : name : node-a