Skip to main content

Kubernetes

Kubernetes Introduction

1. What is Kubernetes?​

  • Kubernetes (K8s) is an open-source container orchestration platform for automating deployment, scaling, and management of containerized applications.
  • It was originally developed by Google and later donated to the Cloud Native Computing Foundation (CNCF).

2. Key Features of Kubernetes:​

  • Automatic Deployment and Rollback: Kubernetes can automatically deploy and rollback applications with zero downtime.
  • Service Discovery and Load Balancing: It provides service discovery and load balancing across containerized applications.
  • Storage Orchestration: Kubernetes allows mounting of storage systems to containers in a seamless manner.
  • Self-Healing: It automatically restarts failed containers and reschedules them on healthy nodes.
  • Auto-Scaling: Kubernetes can automatically scale containerized applications based on CPU and memory utilization.
  • Declarative Configuration: The desired state of the system is defined using YAML configurations.

3. Kubernetes Architecture:​

  • Node: A worker machine that runs containerized applications.
  • Pod: The smallest deployable unit, consisting of one or more containers sharing resources.
  • Service: An abstraction that defines a logical set of Pods and enables external traffic exposure.
  • Cluster: A set of nodes that run containerized applications managed by Kubernetes.
  • Control Plane: The core component that manages the Kubernetes cluster (API Server, Scheduler, Controller Manager, etcd).

4. Kubernetes Objects:​

  • Deployment: Defines the desired state of an application and manages its rollout.
  • Service: Provides a stable endpoint for Pods and load balancing.
  • ConfigMap: Stores configuration data as key-value pairs.
  • Secret: Stores sensitive data like passwords, tokens, and keys.
  • Ingress: Manages external access to services in a cluster.

5. Getting Started with Kubernetes:​

  • Install a Kubernetes cluster (e.g., Minikube for local development, cloud-managed services).
  • Use the kubectl command-line tool to interact with the cluster.
  • Define your application's desired state in YAML configuration files.
  • Apply the configurations using kubectl apply.
  • Monitor the cluster and application state using kubectl get and kubectl describe.

6. Use Cases:​

  • Deploying and managing microservices-based applications.
  • Building and scaling containerized applications in the cloud or on-premises.
  • Automating deployment, scaling, and management of applications.
  • Enabling DevOps practices and Continuous Integration/Continuous Deployment (CI/CD) pipelines.