deployment解决了rc的与svc的label升级关联问题,如果rc的pod的label或者svc的selector有改动必须手动匹配才能建立关联。
deployment通过创建rs来管理容器，rs具有90%的rc特性。

apiVersion: apps/v1
kind: Deployment
metadata:
    name: nginx-deployment
spec:
    replicas: 3
    selector:
      matchLabels:
       app: nginx-deployment
    template:
        metadata:
            labels:
                app: nginx-deployment
        spec:
            containers:
            - name:  nginx-deployment
              image: nginx:1.13
              imagePullPolicy: IfNotPresent
              ports:
              - containerPort: 80

kubectl apply -f nginx-deployment.yml --record //记录每一步的reversion
kubectl get deployment 
kubectl scale deployment nginx-deployment --replicas=3
kubectl set image deployment/nginx-deployment nginx:1.15
kubectl rollback undo deployment/nginx-deployment 
kubectl  rollback status deployment/nginx-deployment 
kubectl rollback history deployment/nginx-deployment 
kubectl rollback undo  deployment/nginx-deployment  --to-reversion=3
.spec.revisionHistoryLimit 设置版本保存值