k8s:core:introduction
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Table of Contents
What is Kubernetes
Kubernetes is a system that runs and manages containerized applications automatically.
Instead of manually running containers, Kubernetes:
- Starts them
- Stops them
- Restarts them when they fail
- Scales them up or down
Concepts category
Kubernetes Concepts
- Cluster Fundamentals
- Cluster
- Control Plane
- Node
- Namespace
- Workloads (Run Applications)
- Pod
- ReplicaSet
- Deployment
- StatefulSet
- DaemonSet
- Job
- CronJob
- Networking
- Service
- ClusterIP
- NodePort
- LoadBalancer
- ExternalName
- Ingress
- Ingress Controller
- NetworkPolicy
- Configuration
- ConfigMap
- Secret
- Storage
- PersistentVolume (PV)
- PersistentVolumeClaim (PVC)
- StorageClass
- Volume
- Security
- ServiceAccount
- RBAC
- Role
- RoleBinding
- ClusterRole
- ClusterRoleBinding
- SecurityContext
- Pod Security
- Scheduling
- NodeSelector
- Node Affinity
- Pod Affinity
- Pod Anti-Affinity
- Taints
- Tolerations
- Autoscaling
- Horizontal Pod Autoscaler (HPA)
- Vertical Pod Autoscaler (VPA)
- Cluster Autoscaler
- Observability
- Logs
- Metrics
- Traces
- Prometheus
- Grafana
- Loki
- Jaeger
- Configuration Management
- Helm
- Kustomize
- Operators
- Ecosystem / Operations
- CI/CD
- GitHub Actions
- GitLab CI
- ArgoCD
- Container Runtime
- containerd
- CRI-O
- Service Mesh
- Istio
- Linkerd
- Cloud Providers
- Amazon EKS
- Google GKE
- Azure AKS
- DigitalOcean DOKS
Simple explanation
Kubernetes = “automated container manager”
—
Real-world example
Imagine you have a web application:
Without Kubernetes:
- You run Docker containers manually
- If one crashes → you restart it yourself
- If traffic increases → you manually add more containers
With Kubernetes:
- You define: “I want 3 instances running”
- Kubernetes ensures 3 instances are always running
- If one crashes → it automatically replaces it
- If traffic increases → it can add more instances automatically
—
Simple analogy
Kubernetes is like a restaurant manager:
- You (developer) define the menu (desired state)
- Kubernetes ensures chefs (containers) are always available
- If a chef leaves → it hires a new one automatically
k8s/core/introduction.1781306512.txt.gz · Last modified: by phong2018