W3M20035.1-cloud-infrastructures

Use Case: Skalierbares Pizza backen mit UI für Metriken Beispiel: Knopf für Pizzaorder wird gedrückt -> Pizzaofen erscheint im UI und backt Pizza (max. Kapazität x Pizzen und Dauer von den Pizzen y min zu Demonstrationszwecken)

Technologie:

• UI (Next.js/React)
• Backend (Typescript/Node.js)
• Oven (C#)
• Minikube/K8s etc.
• Prometheus (Dashboard)
• Ansible (Provisioning und Setup)
• Grafana (Dashboard für Metriken)
• Helm (Kubernetes Deployment)
• Jaeger (Tracing)

Getting started

• Minikube
• kubectl

minikube start
kubectl get pods -A (to verify that everything is running)

Docker commands

Frontend: docker build -f containers/frontend/Dockerfile --tag frontend:latest .
Backend: docker build -f containers/backend/Dockerfile --tag backend:latest .
Oven: docker build -f containers/furnace/Dockerfile --tag oven:latest .

Helm commands

helm dependency build deployment/charts/application/
helm dependency build <path-to-charts>

helm install test deployment/charts/application/
helm install <releasename> <path-to-charts>

helm dependency update deployment/charts/application/
helm upgrade test deployment/charts/application/

helm uninstall test
helm uninstall <releasename>

kubectl get pods (um laufende Pods zu bekommen)
kubectl logs <podname> (Logs des Pods/Container))

To access the frontend:
kubectl port-forward svc/test-frontend 3000:3000

Troubleshooting:

Q: I have a ImagePullBackOff error when reading kubectl get pods
A:

• Build all docker images that can not be found (docker build -t <name-of-image-as-in-helm-values.yaml>:<tag-as-in-helm-values.yaml> in the correct folder) -> see Docker commands
• minikube image load <name-of-built-image>:<tag-of-built-image> for each image
• Verify that the error is gone with kubectl get pods

Q: How do I update my pods to the latest code change? TODO: test again and if working remove this todo
A:

• Build the docker image
• Remove the old docker image from minikube (minikube ssh - docker rmi <image-name> - exit)
• minikube image load <name-of-built-image>:<tag-of-built-image> for the updated image
• helm uninstall <releasename>
• helm install <releasename> <path-to-charts>
• Verify that the error is gone with kubectl get pods and kubectl logs <podname>