Kubernetes cluster command line tool kubectl

1 kubectl summary

kubectl yes Kubernetes Command line tools for clustering , adopt kubectl Be able to manage the cluster itself , And can install and deploy container applications on the cluster .

2 kubernetes command

2.1 kubectl The syntax of the command

kubectl [common] [TYPE] [NAME] [flags]
（1）comand： Specifies the action to be performed on the resource , for example create、get、describe and delete
（2）TYPE： Specify the type of resource , Resource types are case sensitive , Developers can use the singular number 、 Plural and abbreviated forms , for example ：

kubectl get pod pod1
kubectl get pods pod1
kubectl get po pod1

（3）NAME： Specify the name of the resource , Names are also case sensitive . If you omit the name , All resources will be displayed .

kubectl get pods

（4）flags： Specify optional parameters . for example ： You can use -s perhaps -server Parameter assignment Kubernetes API Server The address and port of .

kubectl get node
kubectl get nodes
kubectl get nodes master

Help order
kubectl --help
See a specific operation

kubectl get --help

2.2 Common commands

nginx For example

establish nginx pod

kubectl create deployment nginx --image=nginx

External exposure port

kubectl expose deployment nginx --port=80 --type=NodePort

kubectl get pod, svc

View current health status

kubectl get cs

3 Use command

3.1 check

check pods

#  View all pods  Specify the namespace 
kubectl get pods --all-namespaces

check service

#  Check all service
kubectl get service

3.2 Deployment operation

see

kubectl get deployment

Delete

kubectl get deployment
kubectl delete deployment flask-demo
 perhaps 
kubectl delete-f app.yaml

4 Project deployment

vim app.yaml

# 1  Deployment information 
apiVersion: apps/v1
kind: Deployment #  use deployment Deploy 
metadata:
  name: flask-demo
  namespace: default #  Default namespace 
  labels:
    app: flask-demo
spec:
  replicas: 2 #  Copy settings 1 individual 
  selector:
    matchLabels:
      app: flask-demo
  template:
    metadata:
      labels:
        app: flask-demo
    spec:
      containers: # Container related configuration 
        - name: flask-demo-app
          image: vitcloud/flask_demo:latest #  Mirror address 
          ports: #  Container exposure port 
            - containerPort: 80
          resources:  #  Resources to be used by the container 
            requests:
              cpu: "1000m"
              memory: "1Gi"
            limits:
              cpu: "2000m"
              memory: "2Gi"

# service  Information  ---  Associated with deployment 
apiVersion: v1
kind: Service
metadata:
  name: flask-demo-service
spec:
  selector: # ==== Corresponding 
    app: flask-demo #  Point to pod
  type: NodePort  #  Open service through port 
  ports:
    - name: web
      port: 80
      protocol: TCP
# targetPort: 80 #  Container port 
# nodePort: 30001 #  External exposure port 

Specified file

kubectl apply -f app.yaml

#  see 
kubectl get pods --all-namespaces -o wide
#  View progress 
watch kubectl get pods --all-namespaces -o wide
#  View resource details 
kubectl describe pods flask-demo-77f769cb94-7pw4q