Kubernetes (K8s) is an open-source container orchestration platform. It helps you run, manage, scale, and automate containerized applications — most commonly Docker containers — across a cluster of machines.
Is like an operating system for your containers.
Instead of running one app on one server, Kubernetes lets you run many containers across many servers, and it manages all the complexity for you.
Restarts crashed containers, replaces failed pods
Lets containers find each other without hardcoding IPs
Deploys app updates with zero downtime
Automatically scale apps up/down based on demand
Distributes traffic across services automatically
Store passwords, tokens, configs securely
kube-apiserver: API you talk to via kubectl
etcd: stores the state of the cluster
kubelet: runs on each node, manages containers
kube-proxy: handles networking between pods and services
It’s the industry standard for deploying apps at scale.
Used by big companies like Netflix, Google
Cloud-native jobs increasingly require it.
Cluster info commands:
kubectl cluster-info - Shows cluster details
kubectl get nodes - Lists all nodes in the cluster
kubectl get pods - Lists pods in the current namespace
kubectl get all - Lists all resources (pods, svc, etc.)
kubectl get namespaces - Lists all namespaces
kubectl config current-context - Shows the current context (cluster config)
kubectl proxy - expose Dashboard - for local access
Managing Workloads commands:
kubectl create deployment nginx --image=nginx - Creates a deployment running NGINX
kubectl get deployments - Lists all deployments
kubectl delete deployment nginx - Deletes the nginx deployment
kubectl scale deployment nginx --replicas=3 - Scales nginx deployment to 3 pods
kubectl rollout restart deployment nginx - Restarts the deployment (pods refresh)
Services & Networking commands:
kubectl expose deployment nginx --port=80 --type=NodePort - Creates a service to expose the app
kubectl get svc - Lists all services
kubectl describe svc nginx - Detailed info about the service
YAML Files commands:
kubectl apply -f app.yaml - Applies config from a YAML file
kubectl delete -f app.yaml - Deletes resources defined in the YAML file
kubectl edit deployment nginx - Opens live YAML editor in terminal
kubectl get deployment nginx -o yaml - Shows full YAML config