Kubernetes Architecture Explanation | Part 1

#kubernetes #docker #cicd #fullstack

Kubernetes:

Kubernetes is an open-source container orchestration tool that automates the deployment, scaling, and management of containerized applications. It helps developers and operations teams manage clusters of hosts running containers, ensuring high availability, resource efficiency, and scalability of applications across a distributed environment.

The Kubernetes architecture is like a system that organizes multiple computers to run software applications smoothly. Here’s a simple explanation:

1. Cluster

A cluster is a group of connected computers (nodes) working together. It’s where your applications run.

2. Control Plane

The control plane is the brain of Kubernetes. It manages and controls everything in the cluster. It has three main jobs:

API Server: The communication center where commands and requests come in.
Scheduler: The planner that decides which computer (node) will run which application.
Controller Manager: The overseer that keeps everything in the cluster running as expected.
etcd: The memory that stores all the settings, data, and state of the cluster.

3. Nodes (Worker Machines)

Each node is like a worker that runs parts of your application. It has:

Kubelet: The assistant that makes sure the application runs correctly on the node.
Container Runtime: The engine that runs the containers (e.g., Docker).
Kube-Proxy: The traffic manager that handles networking, making sure apps can talk to each other and users.

4. Pods

A pod is the smallest unit in Kubernetes, like a container box that holds your application. It can have one or more containers (small units of software).

5. Services

A service acts as a bridge that connects users or other applications to the pods. It makes sure that the connection remains stable, even if the pod moves to a different node.

How It Works Together:

The control plane decides where and when your applications run across all the nodes.
Nodes do the actual work of running the applications inside pods.
Services make it easy for apps to connect, and users can access them even if things change.

In short, Kubernetes organizes multiple computers to work together so your applications can run efficiently, scale up, and recover from failures automatically.