Docker vs Kubernetes
| Docker | Kubernetes |
|---|---|
| container tech, isolated env for apps | infra management, multiple containers |
| automated builds and deploy apps - CI | automated scheduling and management of app containers |
| platform for config, build & destribute containers | ecosystem for managing cluster of containers |
Docker Swarm vs Kubernetes
| Docker Swarn | Kubernetes |
|---|---|
| complex install | easy install |
| high learning curve, but powerful | easy to use, limited functionality |
| auto-scaling | manual scaling |
| built in monitoring | N/A |
| manual load balancing | auto load balancing |
Create deplyment
kubectl create deployment example-db-depl --image=abhijitwakchaure/example-db:1.0.0 --port=8081 --replicas=2
OR
kubectl apply -f db-deployment.yml
Create service
kubectl apply -f app-service.yml
Expose deployment
kubectl expose deployment example-db-depl --name=example-db-srv --port=8081 --target-port=8081 --type ClusterIP
Scale deployment
kubectl scale deployment example-app-depl --replicas=5
Test with multiple requests
for n in {1..100}; do printf "%5s" "$n. "; curl http://192.168.49.2:31277; echo ""; sleep 0.3; done
Inject linkerd
kubectl get deploy -o yaml | linkerd inject - | kubectl apply -f -
Helm Commands
Create new chart
helm create example-chart
Install chart
Test the rendered/compiled yaml files before install
helm install my-chart example-chart --dry-run
Now deploy the chart
helm install my-chart example-chart
OR using custom values
helm install my-chart example-chart -f customValues.yml
Delete chart
helm delete my-chart
