RC主要作用就是用来确保容器应用副本始终保持在用户定义的数量，如果有容器异常退出，会自动创建新的 Pod来代理，异常多出来的容器会被系统回收 RS本质与RC没有什么不同，可以认为RS是RC的升级版，并且支持集合式的selector
RS实例
apiVersion: extensions/v1beta1 kind: ReplicaSet metadata: name: frontend spec: replicas: 2 selector: matchLabels: tier: frontend template: metadata: labels: tier: frontend spec: containers: - name: nginx image: nginx:v1 env: - name: GET_HOSTS_FROM value: dns ports: - containerPort: 80 RS与Deployment的关联
Deployment为Pod和Rs提供申明式定义方法，用来代理以前的RC来方便管理应用。 下面使用Deployment部署一个简单的nginx应用
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 2 template: metadata: labels: app: nginx spec: containers: - name: nginx image: nginx:latest imagePullPolicy: IfNotPresent ports: - containerPort: 80 //deployment使用apply创建，也可以使用create [root@k8s-master yaml]# kubectl apply -f nginx-deploy.yaml //查看生成的pod [root@k8s-master yaml]# kubectl get pod NAME READY STATUS RESTARTS AGE nginx-deployment-698c64b949-rsldr 1/1 Running 0 20h nginx-deployment-698c64b949-s5xxk 1/1 Running 0 20h [root@k8s-master yaml]# kubectl get deployment nginx-deployment -o wide NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR nginx-deployment 2/2 2 2 20h nginx nginx:latest app=nginx Deployment的扩容
//是用scale命令对nignx-deployment的容器扩容 [root@k8s-master yaml]# kubectl scale deployment nginx-deployment --replicas=10 deployment.extensions/nginx-deployment scaled //查看扩容结果 [root@k8s-master yaml]# kubectl get pod NAME READY STATUS RESTARTS AGE nginx-deployment-698c64b949-7bb8c 1/1 Running 0 9s nginx-deployment-698c64b949-7mlcc 1/1 Running 0 9s nginx-deployment-698c64b949-8qn2w 1/1 Running 0 10s nginx-deployment-698c64b949-m8x7k 1/1 Running 0 10s nginx-deployment-698c64b949-mx674 1/1 Running 0 9s nginx-deployment-698c64b949-mxw84 1/1 Running 0 9s nginx-deployment-698c64b949-rsldr 1/1 Running 0 20h nginx-deployment-698c64b949-s5xxk 1/1 Running 0 20h nginx-deployment-698c64b949-t4h4l 1/1 Running 0 9s nginx-deployment-698c64b949-vx78j 1/1 Running 0 10s Deployment的镜像更新
//使用set image镜像更新，应用更新会新生成一个对应rs //格式 kubectl set iamges deployment/deployment名称 容器名=容器版本 kubectl set image deployment/nginx-deployment nginx=nginx:1.16.1 Deployment的回滚
kubectl rollout undo deployment/nginx-deployment Deployment的回滚相关其他命令
- kubectl rollout status 回滚状态信息
- kubectl rollout history 回滚历史信息