What Is Kubernetes? Architecture Overview

Introduction Of Kubernetes

• Kubernetes is an open-source container orchestration tool, It's also called as K8s.

• It is developed by Google and currently it’s maintained by Cloud Native Computing Foundation (CNCF).

• It helps us to automate the deployment, scaling, and management of containerized application which is Docker container.

• Kubernetes helps us to manage hundreds and thousands of applications efficiently.

Why we use Kubernetes to manage container?

Before Kubernetes, DevOps team uses scripts or tools to manage containers which is inefficient.

• Deployment – It automatically starts the container on the available server.

• Auto-scaling – It helps adding and removing container based on the load.

• Load balancing – Distributes the load equally between containers.

• Self-healing – Automatically replaces the crashed containers.

Instead of managing container manually, Kubernetes automates those processes. Therefore, Kubernetes acts as a manager for all the container.

Kubernetes Architecture

Kubernetes architecture is a Master – Worker model.

It mainly contains two types of nodes:

1. Master node (Control plane)

2. Worker node

These nodes together form a Cluster.

Master node (Control plane)

• It is the brain of Kubernetes architecture.

• It manages and controls the whole cluster.

Components

1. API Server – It’s the main thing in this node. This is where all the communication happens.

2. Controller Manager – It maintains the state of the container. It ensures cluster’s desired state, by compare the desired state with actual state.

3. ETCD – It is the database where all the cluster configuration and state are stored. It provides the desired state to controller manager from the database.

4. Scheduler – It decides which node should run and create a new pod based on the CPU%, RAM, and load.

Worker node

Applications (container) are running inside the worker node.

Components:

1. Kubelet – Main agent that runs on each worker node. It checks the status of the node and communicates with the API Server.

2. Kube-proxy – It manages the communication between Pods/services.

3. Container Runtime Interface – It’s the container engine, like Docker containers.

Conclusion

Kubernetes provides a powerful and automated tool for deploying, managing, and scaling containerized applications. Its master–worker architecture make sure that workloads run efficiently, reliably, and with minimal manual effort. The control plane manages the entire cluster, while worker nodes manage the actual execution of applications.

With auto-scaling, load balancing, and self-healing, Kubernetes simplifies complex operational tasks and ensures high availability. Overall, Kubernetes has become the backbone of modern cloud-native infrastructure, enabling organizations to deliver applications faster, more securely, and at scale.