Kubernetes Fundamentals
Introduction to Kubernetes
Kubernetes is a powerful container orchestration platform designed to automate deployment, scaling, and management of containerized applications. As an open-source system, it provides robust cluster management capabilities for Docker containers and other containerized workloads.
Core Concepts and Architecture
Kubernetes operates through a cluster-based architecture with several key components:
graph TD
A[Master Node] --> B[API Server]
A --> C[Controller Manager]
A --> D[Scheduler]
A --> E[etcd]
A --> F[Worker Nodes]
F --> G[Kubelet]
F --> H[Container Runtime]
Component |
Description |
Function |
Master Node |
Cluster control plane |
Manages overall cluster state |
Worker Nodes |
Application execution environment |
Runs containerized applications |
Kubelet |
Node agent |
Ensures containers are running |
Pod |
Smallest deployable unit |
Contains one or more containers |
Basic Kubernetes Deployment Example
Here's a simple Pod deployment manifest for Ubuntu 22.04:
apiVersion: v1
kind: Pod
metadata:
name: nginx-pod
spec:
containers:
- name: nginx
image: nginx:latest
ports:
- containerPort: 80
To deploy this Pod, use the following command:
kubectl apply -f nginx-pod.yaml
Key Kubernetes Features
- Container orchestration
- Automatic scaling
- Self-healing mechanisms
- Service discovery and load balancing
- Rolling updates and rollbacks
Kubernetes simplifies complex container management, enabling developers to focus on application development rather than infrastructure complexity.