SpringBoot服务迁移至kubernetes

Posted 2022-09-21 潇湘海棠

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1.准备Docker编译工作

1.1基础准备之安装java环境

1.安装java环境
[root@kn-server-master01-13 springboot]# yum install java -y

1.2安装maven

2.安装Maven，因为要使用Maven来进行编译安装。
maven官方下载地址: https://maven.apache.org/download.cgi
3.下载.gz压缩包到本地然后解压。
[root@kn-server-master01-13 springboot]# tar -xvf apache-maven-3.8.6-bin.tar.gz 
4.修改配置文件指定包的路径即可。
vim /etc/profile
export M2_HOME=/usr/local/apache-maven-3.8.6
export PATH=$M2_HOME/bin:$PATH
5.重载配置
# source /etc/profile
6.修改maven的源获取地址为aliyun
https://maven.aliyun.com/repository/public

7.centos可以直接执行以下命令即可
[root@kn-server-master01-13 springboot]# yum install maven -y

1.3对Springboot应用进行编译并运行

1.解压应用的tar包
[root@kn-server-master01-13 springboot]# tar -xvf springboot-helloworld-jar.tar.gz 
2.执行编译操作
[root@kn-server-master01-13 springboot-helloworld]# mvn clean package
[INFO] Scanning for projects...
Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/com/google/guava/guava/11.0.2/guava-11.0.2.jar
Downloaded from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/vafer/jdependency/0.7/jdependency-0.7.jar (12 kB at 4.4 kB/s)
Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar
Downloaded from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/commons-io/commons-io/1.3.2/commons-io-1.3.2.jar (88 kB at 32 kB/s)
Downloaded from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/asm/asm-util/3.2/asm-util-3.2.jar (37 kB at 13 kB/s)
Downloaded from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar (33 kB at 11 kB/s)
Downloaded from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/asm/asm-analysis/3.2/asm-analysis-3.2.jar (18 kB at 5.8 kB/s)
Downloaded from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/com/google/guava/guava/11.0.2/guava-11.0.2.jar (1.6 MB at 495 kB/s)
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  02:26 min
[INFO] Finished at: 2022-09-20T14:28:33+08:00
[INFO] ------------------------------------------------------------------------


3.编译执行完成后当前目录下会有一个jar包
root@ks-master01-10:/cloud-Native/springboot/springboot-helloworld/target# ll
total 12460
drwxr-xr-x 6 root root     4096 Sep 20 14:28 ./
drwxr-xr-x 4 root root     4096 Sep 20 14:27 ../
drwxr-xr-x 3 root root     4096 Sep 20 14:27 classes/
-rw-r--r-- 1 root root 12726619 Sep 20 14:28 demo-service-1.0.jar
-rw-r--r-- 1 root root     3556 Sep 20 14:28 demo-service-1.0.jar.original
drwxr-xr-x 3 root root     4096 Sep 20 14:27 generated-sources/
drwxr-xr-x 2 root root     4096 Sep 20 14:28 maven-archiver/
drwxr-xr-x 3 root root     4096 Sep 20 14:27 maven-status/


4.运行jar包
[root@kn-server-master01-13 target]# java -jar demo-service-1.0.jar
seconds (JVM running for 2.974)
2022-09-20 15:32:30.399  INFO 2344 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring FrameworkServlet dispatcherServlet
2022-09-20 15:32:30.399  INFO 2344 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet dispatcherServlet: initialization started
2022-09-20 15:32:30.413  INFO 2344 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet dispatcherServlet: initialization completed in 14 ms

1.4访问测试；

1.查看8080端口是否启动
root@kn-server-master01-13 ~]# netstat -tnlp | grep 8080
tcp6       0      0 :::8080                 :::*                    LISTEN      13518/java  
2.curl访问测试
[root@kn-server-master01-13 ~]# curl 10.0.0.13:8080/
Hello Knative

SpringBoot服务迁移至kubernetes_SpringBoot

2.准备Spring应用迁移至kubernetes

2.1准备Deployment配置片段；

[root@kn-server-master01-13 ~]# cat springboot-deploy.yaml 
apiVersion: apps/v1
kind: Deployment
metadata:
  name: springboot
spec:
  replicas: 3
  selector:
    matchLabels:
      app: spring
  template:
    metadata:
      labels:
        app: spring
    spec:
      containers:
      - name: springboot
        image: registry.cn-hangzhou.aliyuncs.com/lengyuye/springboot:v1.0
        ports:
        - name: http
          containerPort: 8080
        env:            # 传递初始堆内存和最大堆内存占用
        - name: XMS_OPTS
          valueFrom:
            resourceFieldRef:
              resource: requests.memory
        - name: XMX_OPTS
          valueFrom:
            resourceFieldRef:
              resource: limits.memory
        resources:
          requests:
            memory: 150Mi
          limits:
            memory: 300Mi
        readinessProbe:         # 就绪探针；如果端口不存活，则从负载均衡中移除
          tcpSocket:
            port: http          # http是一个名字；它会获取这个名字对应的端口；
          initialDelaySeconds: 10
          failureThreshold: 3
        
        livenessProbe:          # 存活探针；获取url，状态码不对那么则触发重启操作
          httpGet:
            path: /
            port: http
          initialDelaySeconds: 10
          failureThreshold: 3
[root@kn-server-master01-13 ~]# kubectl apply -f springboot-deploy.yaml 
deployment.apps/springboot created

查看Pod是否运行

[root@kn-server-master01-13 ~]# kubectl get pods
NAME                        READY   STATUS    RESTARTS   AGE
springboot-bd6f67ff-c6dtn   1/1     Running   0          107s
springboot-bd6f67ff-jcjst   1/1     Running   0          107s
springboot-bd6f67ff-pk8gz   1/1     Running   0          107s

2.2准备Service配置文件

[root@kn-server-master01-13 ~]# cat springboot-svc.yaml 
apiVersion: v1
kind: Service
metadata:
  name: spring-svc
spec:
  type: NodePort
  clusterIP:
  selector:
    app: spring
  ports:
  - name: http
    protocol: TCP
    port: 8080
    targetPort: 8080   # 后端Pod监听什么端口就写什么端口。要不然到达Service的请求转发给Pod，Pod没有那个端口也没用。一定真正转发到后端程序监听的端口。如果没有特殊情况的话，ServicePort和TargetPort保持一致。NodePort可以不用指定。
    nodePort:        # 正常情况下应由系统自己分配，除非事先能够明确知道它不会与某个现存的Service资源产生冲突，没有特别需求，留给系统自动配置总是好的选择。
[root@kn-server-master01-13 ~]# kubectl apply -f springboot-svc.yaml 
service/spring-svc created

查看Serivces资源是否关联Pod；

SVC类型为NodePort
[root@kn-server-master01-13 ~]# kubectl get svc
spring-svc              NodePort       10.96.14.100    <none>                                                 8080:32629/TCP                                       100m

已经关联到后端Pod；
[root@kn-server-master01-13 ~]# kubectl describe svc spring-svc
Name:                     spring-svc
Namespace:                default
Labels:                   <none>
Annotations:              <none>
Selector:                 app=spring
Type:                     NodePort
IP Family Policy:         SingleStack
IP Families:              IPv4
IP:                       10.96.14.100
IPs:                      10.96.14.100
Port:                     http  8080/TCP
TargetPort:               8080/TCP
NodePort:                 http  32629/TCP
Endpoints:                192.168.2.46:8080,192.168.2.47:8080,192.168.2.48:8080
Session Affinity:         None
External Traffic Policy:  Cluster
Events:                   <none>

类型为NodePort，在集群内外都可以访问；
[root@kn-server-master01-13 springboot-helloworld]# curl 10.96.14.100:8080/
Hello Knative

2.3集群外测试访问；

SpringBoot服务迁移至kubernetes_kubernetes_02

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