https://kubernetes.io/docs/concepts/workloads/controllers/deployment/
Deployment为Pod和ReplicaSet提供声明式更新。
你只需要在 Deployment 中描述您想要的目标状态是什么，Deployment controller 就会帮您将 Pod 和ReplicaSet 的实际状态改变到您的目标状态。您可以定义一个全新的 Deployment 来创建 ReplicaSet 或者删除已有的 Deployment 并创建一个新的来替换。

注意：您不该手动管理由 Deployment 创建的 ReplicaSet，否则您就篡越了 Deployment controller 的职责！下文罗列了 Deployment 对象中已经覆盖了所有的用例。如果未有覆盖您所有需要的用例，请直接在 Kubernetes 的代码库中提 issue。

1.Delpyment演示

1.1 deployment_nginx.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  labels:
    app: nginx
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.12.2
        ports:
        - containerPort: 80

1.2 创建deployment

kubectl create -f deployment_nginx.yml
kubectl get deployment
kubectl get rs
kubectl get pods
kubectl get deployment -o wide

1.3 deployment升级

针对目前的nginx1.12升级成1.13。

kubectl set image deployment nginx-deployment nginx=nginx:1.13
kubectl get deployment
kubectl get deployment -o wide
kubectl get pods

1.4 deployment 回滚

deployment查看历史版本：

kubectl rollout history deployment nginx-deployment

deployment 回滚

kubectl rollout undo deployment nginx-deployment

1.5 deployment 暴露端口

kubectl get node
kubectl get node -o wide
kubectl expose deployment nginx-deployment --type=NodePort
#查看node节点暴露的端口30960
kubectl get svc
#进入minikube查看ip地址192.168.99.100
minikube ssh