basic command

• Initialize the cluster

  sudo kubeadm init --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=192.168.33.242 --kubernetes-version stable-1.11 -v 10
  

• View the logs

  kubectl logs -f kubernetes-dashboard-767dc7d4d-f8r8l -n kube-system
  

• Forward the port

  kubectl port-forward pod/guids-796989bbbb-qj2nl 9000:9000
  

• Expose the port (By NodePort)

  kubectl expose deployment/kubernetes-bootcamp --type="NodePort" --port 8080
  
  kubectl expose deployments hello-world
  

• Label a pod

  kubectl label pod guids-796989bbbb-qj2nl app=guids
  
  kubectl get pods -l app=guids
  

• Tear down the cluster

  kubectl drain neo --delete-local-data --force --ignore-daemonsets
  kubectl delete pod,service baz foo
  

• Re-add the node

  service kubelet restart
  kubectl uncordon neo
  

• Various get

  kubectl get nodes
  kubectl get pods
  kubectl get services
  kubectl get deployments -o wide
  kubectl get all -n kube-system
  kubectl get storageclass
  kubectl api-resources
  

• Describe

  kubectl describe services guids
  

• Create a deployment

  kubectl run hello-world --replicas=2 --labels="run=load-balancer-example" --image=neocxf/hello-world  --port=8080
  

• View the pod name

  export POD_NAME=$(kubectl get pods -o go-template --template '{{range .items}}{{.metadata.name}}{{"\n"}}{{end}}')
  

• Configure default storage class

  kubectl patch storageclass standard -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'
  
  kubectl create -f https://k8s.io/examples/pods/storage/pv-volume.yaml
  kubectl get pv task-pv-volume
  kubectl create -f https://k8s.io/examples/pods/storage/pv-claim.yaml
  kubectl get pvc task-pv-claim
  

• How to set a pv and pvc

  kubectl scale sts web --replicas=2
  kubectl delete pvc www-web-2
  kubectl patch pv task-pv-volume3 # delete pvc in pv yaml
  kubectl get pv                   # now we have an available pv
  

• Print the join command

  kubeadm token create --print-join-command
  

• ConfigMap

  kubectl create configmap example-redis-config --from-file=redis-config
  kubectl get configmap example-redis-config -o yaml
  

• Redis-Master-Slave-Frontend deploy

2. How Kubernetes work

2.1 Main components