Introduction to Kubernetes (K8S)

Introduction to Kubernetes (K8s)

Are you interested in learning about Kubernetes, often abbreviated as K8s? This tutorial will guide you through the basic concepts and components of Kubernetes, a powerful open-source platform for automating the deployment, scaling, and operation of application containers across clusters of hosts. This is perfect for students, professionals, and tech enthusiasts who want to understand the fundamentals of Kubernetes and its role in modern application development and deployment.

What is Kubernetes?

Kubernetes, often referred to as K8s, is an open-source container orchestration platform designed to automate the deployment, scaling, and management of containerized applications. It was originally developed by Google and is now maintained by the Cloud Native Computing Foundation (CNCF).

Key Features of Kubernetes

• Automated Rollouts and Rollbacks: Kubernetes can manage the rollout of changes to your application or its configuration, ensuring that changes are applied in a controlled manner. If something goes wrong, Kubernetes can roll back the changes.
• Service Discovery and Load Balancing: Kubernetes can expose a container using the DNS name or its own IP address. It can load balance across containers to ensure consistent and reliable performance.
• Storage Orchestration: Kubernetes can automatically mount the storage system of your choice, such as local storage, public cloud providers, and more.
• Self-healing: Kubernetes restarts containers that fail, replaces and reschedules containers when nodes die, and kills containers that don’t respond to your user-defined health check.
• Secret and Configuration Management: Kubernetes lets you store and manage sensitive information, such as passwords, OAuth tokens, and SSH keys.

Core Concepts of Kubernetes

1. Cluster

A Kubernetes cluster consists of a set of worker machines, called nodes, that run containerized applications. Every cluster has at least one worker node.

2. Nodes

A node is a worker machine in Kubernetes. Each node contains the services necessary to run pods and is managed by the master components.

3. Pods

A pod is the smallest and simplest Kubernetes object. A pod represents a set of running containers on your cluster. Pods typically run a single primary container, but they can also include other containers that are tightly coupled and need to share resources.

4. Services

A Kubernetes service is an abstraction which defines a logical set of pods and a policy by which to access them. Services enable the decoupling of workloads and ensure that applications remain available despite failures or changes.

5. Deployments

A deployment provides declarative updates to applications. You describe a desired state in a deployment object, and Kubernetes changes the actual state to match the desired state at a controlled rate.

6. Namespaces

Namespaces provide a mechanism for isolating groups of resources within a single cluster. Namespaces are intended for use in environments with many users spread across multiple teams or projects.

How Kubernetes Works

Kubernetes follows a client-server architecture and includes the following core components:

• Kube-apiserver: The API server is a component of the Kubernetes control plane that exposes the Kubernetes API.
• etcd: A consistent and highly-available key-value store used as Kubernetes' backing store for all cluster data.
• Kube-scheduler: Watches for newly created pods with no assigned node and selects a node for them to run on.
• Kube-controller-manager: Runs controller processes, which regulate the state of the system.
• Kubelet: An agent that runs on each node in the cluster. It ensures that containers are running in a pod.
• Kube-proxy: Maintains network rules on nodes. These network rules allow network communication to your pods from network sessions inside or outside of your cluster.
• Container Runtime: The software responsible for running containers.

Conclusion

By the end of this tutorial, you should have a solid understanding of Kubernetes, its core concepts, and how it facilitates the management and orchestration of containerized applications. Kubernetes is a powerful tool that has become a cornerstone in modern DevOps practices, enabling scalable and resilient application deployments.

Understanding Kubernetes is essential for anyone involved in software development and IT operations. Whether you’re a student, professional, or tech enthusiast, this tutorial provides the foundational knowledge you need to get started with Kubernetes.

For a detailed step-by-step guide, check out the full article: https://www.geeksforgeeks.org/introduction-to-kubernetes-k8s/.