Spring Boot Microservices labs on K8s

1. Install Docker Desktop and enable kubernetes service

Note : For new versions of Docker Desktop, run the below command

Spring Cloud Kubernetes requires access to Kubernetes API in order to be able to retrieve a list of addresses of pods running for a single service. If you use Kubernetes you should just execute the following command:

kubectl create clusterrolebinding admin --clusterrole=cluster-admin --serviceaccount=default:default

2. execute the below steps to run the applications on K8s
   kubectl create deployment simple-rest-api --image=jbossramana/microservices:simple
   kubectl expose deployment simple-rest-api --type=LoadBalancer --port=8080
   kubectl create deployment other-rest-api --image=jbossramana/microservices:other
   kubectl expose deployment other-rest-api --type=LoadBalancer --port=8081

• Take a replication controller, service or pod and expose it as a new Kubernetes Service

3. Test the appliction url's

http://localhost:8080/simple
http://localhost:8081/other [this service calls simple service using Ribbon Client and K8s service registry]

4. Explain K8s commands

kubectl explain deployment(s)
kubectl explain pod(s)
kubectl explain service(s)

5. K8s commands to get deployment, service and pods information :

kubectl get pod(s)
kubectl get service(s)
kubectl get deployment(s) kubectl get event(s)
kubectl get replicaset(s)

6. To edit the deployment kubectl edit deployment simple-rest-api #minReadySeconds: 15

7. K8s commands to delete the deployment and services
   kubectl delete service other-rest-api
   kubectl delete deployment other-rest-api

8. To scale the application
   kubectl scale deployment simple-rest-api --replicas=3

To autoscale: kubectl autoscale deployment simple-rest-api --max=5 --cpu-percent=50

9. Finding a Pod’s Cluster IP kubectl get pod -o wide

10. Finding a Service’s IP kubectl get service --all-namespaces

11. Other useful K8s commands

kubectl explain pods
kubectl describe pod simple-rest-api-678ddff668-d9pmt
kubectl get componentstatuses
kubectl get all
kubectl get all -o wide
kubectl rollout history deployment simple-rest-api
kubectl logs simple-rest-api-678ddff668-d9pmt
kubectl delete all -l app=hello-world-rest-api
kubectl delete all -l app=simple-rest-api

1. Enable virtualization @ BIOS
2. In windows -> Advanced settings -> Advanced -> Performance -> Data Execution Prevention -> Turn on DEP for all programs and sevices except those i select
3. uncheck Hyper-V
4. uncheck Windows Hypervisor Platform
5. uncheck Virtual Machine Platform
6. uninstall vmware
7. restart the server
8. enable Hyper-V
9. restart the server
10. Install docker desktop

1. right click -> docker-desktop
2. select settings
3. kubernetes -> select all options

kubectl version

kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v1.10.1/src/deploy/recommended/kubernetes-dashboard.yaml

We can access Dashboard using the kubectl command-line tool by running the following command:

kubectl proxy Starting to serve on 127.0.0.1:8001

curl http://localhost:8001/api

Go to http://localhost:8001/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/ on Browser

kubectl apply -f dashboard-adminuser.yml
kubectl apply -f admin-role-binding.yml

kubectl -n kube-system describe secret
$(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')

Copy the data -> token In the browser => select token option -> paste the above token