kubernetes入门之--StatefulSet

在开始写之前我们先来简单了解一下kubernetes的 StatefulSets，大致概括为，有状态的集合，管理所有有状态的服务，以下是官网上StatefulSets的几个特性
1.稳定，独特的网络标识符。
2.稳定，持久的存储。
3.有序，优雅的部署和扩展。
4.有序的自动滚动更新。

常见的资源

• pod
• RelicationController
• StatefulSets
  • 特点
    • 可扩容
    • 有序
    • pod 索引唯一
    • 有状态
  • 使用场景
    • 对唯一性，有序性要求较高的pod
    • 集群容器启动时示例必须相互感知
• ConfigMap
  接下来我们通过启动服务器来演示StatefulSet

application.yaml

---

我们在idea的Eureka-server服务中创建application.yaml，我们的目的是让A注册进B，B也注册进A，那么我们需要创建两个yaml
贴出示例yaml

spring:
  application:
    name: eureka-server
server:
  port: 8761 #eureka默认端口号8761
eureka:
  client:
    register-with-eureka: false
    fetch-registry: false
    service-url:
      defaultZone: http://server2:8760/eureka
    instance:
      hostname: server1
  server:
    enable-self-preservation: false

appllication-node.yaml

接下来我们接着贴出第二个yaml

spring:
  application:
    name: eureka-server
server:
  port: 8760 #eureka默认端口号8760
eureka:
  client:
#    register-with-eureka: false
#    fetch-registry: false
    service-url:
      defaultZone: http://server3:8762/eureka
    instance:
      hostname: server2
  server:
    enable-self-preservation: false

好然后直接启动eureka服务，这个时候我们需要注意的是在Edit Configurations上勾选如图，便于我们二次启动


最后在我们两次都启动过eureka服务之后，我们在网页上直接访问applocation.yaml的端口号localhost:8761

然后同样的访问：8760的端口号这样我们就会发现，第一个yaml注册到第二个yaml里面，…
ok 接下来我们在eureka-server的目录下创建eureka.yaml文件，并且配置容器

apiVersion: v1
kind: Service
metadata:
  name: eureka-service
  labels:
    app: eureka-server
spec:
  selector:
    app: eureka-server
  type: NodePort
  ports:
    - port: 8761
      nodePort: 30001
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: eureka-server
  labels:
    app: eureka-server
spec:
  replicas: 2
  selector:
   matchLabels:
     app: eureka-server
  serviceName: eureka-service
  template:
    metadata:
      labels:
        app: eureka-server
    spec:
      volumes:
        - name: jar-location
          hostPath:
            path: /root/apps/eureka-server-0.0.1-SNAPSHOT.jar
      containers:
        - name: eureka-container
          image: java
          imagePullPolicy: IfNotPresent
          workingDir: /apps
          env:
            - name: NODE
              value: "eureka-server-0.eureka-service.default.svc.cluster.local"
            - name: NODE1
              value: "eureka-server-1.eureka-service.default.svc.cluster.local"
#          resources:
#            requests:
#              memory: "256m"
#            limits:
#              memory: "256m"
          volumeMounts:
            - mountPath: /apps/eureka-server-0.0.1-SNAPSHOT.jar
              name: jar-location
          command:
            - "java"
            - "-jar"
            - "eureka-server-0.0.1-SNAPSHOT.jar"

然后我们更改application.yaml的配置

spring:
  application:
    name: eureka-server
server:
  port: 8761 #eureka默认端口号8761
eureka:
  client:
#register-with-eureka: false
    ##    fetch-registry: false
    service-url:
      defaultZone: http://${NODE:locahost}:8761/eureka,http://${NODE1:locahost}:8761/eureka
    instance:
#      hostname: ${NODE1_HOST_NAME: server1}
  server:
    enable-self-preservation: false

接下来就是打开Gradle的Tasks的build 进行打包项目为jar，然后把jar包上传到finalshell的服务器上进行部署，并且创建Eureka.yaml文件

apiVersion: v1
kind: Service
metadata:
  name: eureka-service
  labels:
    app: eureka-server
spec:
  selector:
    app: eureka-server
  type: NodePort
  ports:
    - port: 8761
      nodePort: 30001
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: eureka-server
  labels:
    app: eureka-server
spec:
  replicas: 2
  selector:
   matchLabels:
     app: eureka-server
  serviceName: eureka-service
  template:
    metadata:
      labels:
        app: eureka-server
    spec:
      volumes:
        - name: jar-location
          hostPath:
            path: /root/apps/eureka-server-0.0.1-SNAPSHOT.jar
      containers:
        - name: eureka-container
          image: java
          imagePullPolicy: IfNotPresent
          workingDir: /apps
          env:
            - name: NODE
              value: "eureka-server-0.eureka-service.default.svc.cluster.local"
            - name: NODE1
              value: "eureka-server-1.eureka-service.default.svc.cluster.local"

#          resources:
#            requests:
#              memory: "256m"
#            limits:
#              memory: "256m"
          volumeMounts:
            - mountPath: /apps/eureka-server-0.0.1-SNAPSHOT.jar
              name: jar-location
          command:
            - "java"
            - "-jar"
            - "eureka-server-0.0.1-SNAPSHOT.jar"

接下来我们就在finalshell上传项目的jar包以及yaml文件到服务器
1.kubectl detele -f eureka.yaml

2. kubectl create -f eureka.yaml

3 kubectl get svc

然后docker-demo-service已经占用我们的30001的端口了，
删除

重新get svc就能看到name变成了eureka-service的名字

ok 这个时候已经差不多就剩启动容器了

4.查看状态

kubectl  get pod

这个时候name已经是有序状态了

5.启动容器

kubectl logs  eureka-server-0

6访问路径

curl http://localhost:30001

好了 这个时候容器已经启动完毕，访问也完毕，大功告成！
接下来的kuberbetes的教程请继续关注！！！