Unit 10 - Kubernetes

Overview

This unit introduces Kubernetes (K8s), an open-source container orchestration platform that automates the deployment, scaling, and management of containerized applications. The unit covers:

  • Understanding Kubernetes Architecture - Nodes, Control Plane, and Cluster Components.
  • Installing K3s - A lightweight Kubernetes distribution optimized for resource efficiency.
  • Interacting with Kubernetes - Using kubectl to manage and troubleshoot clusters.
  • Deploying Applications - Creating and managing Pods, Deployments, and Services.
  • Security and Best Practices - Implementing security measures and troubleshooting issues.

Kubernetes plays a critical role in modern enterprise infrastructure, enabling scalability, high availability, and automation in cloud-native applications.

Learning Objectives

By the end of this unit, learners will:

  1. Understand the Core Concepts of Kubernetes:

    • Define Kubernetes and explain its role in container orchestration.
    • Differentiate between Kubernetes vs. PaaS (Platform as a Service).

  2. Deploy and Manage Kubernetes Clusters:

    • Install K3s and verify its functionality.
    • Manage cluster resources using kubectl.

  3. Perform Basic Kubernetes Operations:

    • Create and manage Pods, Deployments, and Services.
    • Understand the role of Namespaces, ConfigMaps, and Secrets.

  4. Troubleshoot Kubernetes Clusters:

    • Identify common cluster issues and validate node status.
    • Diagnose networking and pod scheduling problems.

  5. Apply Security Best Practices in Kubernetes:

    • Secure containerized applications using best practices.
    • Implement Kubernetes Pod Security Standards.

Relevance & Context

Kubernetes is a foundational technology in modern DevOps and cloud computing. Understanding it is critical for system administrators, DevOps engineers, and site reliability engineers (SREs) for several reasons:

  • Scalability & Automation - Automates containerized application deployments, scaling, and management.
  • Resource Efficiency - Optimizes workload distribution across multiple nodes.
  • Infrastructure as Code (IaC) - Kubernetes configurations can be defined declaratively using YAML.
  • Cross-Cloud Compatibility - Supports deployment across on-premises, hybrid, and multi-cloud environments.
  • High Availability & Self-Healing - Detects and replaces failed instances automatically.

Prerequisites

Before beginning this unit, learners should have:

  • A working knowledge of Linux system administration.
  • Experience using the command line (bash, ssh, vim).
  • Familiarity with containers and tools like Docker.
  • Basic networking knowledge, including IP addressing and port management.

Key Terms and Definitions

Kubernetes (K8s)

K3s

Control Plane

Nodes

Pods

Deployments

Services

Kubelet

Scheduler

ETCD

Kube-proxy

Static Pod