第五课 Kubernetes生产级实践-多类型业务迁移到k8s

第五课 Kubernetes生产级实践-多类型业务迁移到k8s

tags:

• k8s
• 慕课网

categories:

• 定时任务迁移
• SpringBoot任务迁移
• 传统dubbo服务迁移
• 传统web服务迁移

第一节 定时任务迁移K8s

1. https://hub.docker.com/ 去找基础镜像。
2. 选择基础镜像。docker pull openjdk:8-jre-alpine

docker pull openjdk:8-jre-alpine
git clone https://gitee.com/qnhyn/mooc-k8s-demo-docker.git && cd /mooc-k8s-demo-docker/cronjob-demo
yum -y install java-1.8.0-openjdk  maven
# 编译运行测试
mvn package && cd target
java -cp cronjob-demo-1.0-SNAPSHOT.jar com.mooc.demo.cronjob.Main
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3. 写镜像文件Dockerfile

FROM openjdk:8-jre-alpine
COPY target/cronjob-demo-1.0-SNAPSHOT.jar /cronjob-demo.jar
ENTRYPOINT ["java", "-cp", "/cronjob-demo.jar", "com.mooc.demo.cronjob.Main"]
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4. 构建基础镜像, 上传到自己的镜像仓库。

docker build -t cronjob:v1 .
# 运行镜像
docker run -it cronjob:v1
docker tag cronjob:v1 192.168.242.130/k8s/cronjob:v1
docker push 192.168.242.130/k8s/cronjob:v1
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5. 制作k8s服务并调度。这里没有网络，没有接口所以不用服务发现。cronjob.yaml

apiVersion: batch/v1beta1
kind: CronJob
metadata:
  name: cronjob-demo
spec:
  schedule: "*/1 * * * *"
  successfulJobsHistoryLimit: 3
  suspend: false
  concurrencyPolicy: Forbid
  failedJobsHistoryLimit: 1
  jobTemplate:
    spec:
      template:
        metadata:
          labels:
            app: cronjob-demo
        spec:
          restartPolicy: Never
          containers:
          - name: cronjob-demo
            image: 192.168.242.130/k8s/cronjob:v1
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6. k8s调度观察。

kubectl create -f cronjob.yaml
kubectl get cronjob
# 查看运行的执行机
kubectl get pods -o wide
# 查看结束容器
docker ps -a | grep cronjob
# 查看容器日志
docker logs 564f6f1796b4
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第二节 Spring Boot任务迁移K8s

1. 构建镜像和上面基本一样。

cd springboot-web-demo
# 编译运行测试
mvn package && cd target
# 用jar 命令看jar打包的具体内容
jar -tf springboot-web-demo-1.0-SNAPSHOT.jar
# 运行服务
java -jar springboot-web-demo-1.0-SNAPSHOT.jar
# 访问服务
http://192.168.242.130:8080/hello?name=Michael
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3. 写镜像文件Dockerfile

FROM openjdk:8-jre-alpine
COPY target/springboot-web-demo-1.0-SNAPSHOT.jar /springboot-web.jar
ENTRYPOINT ["java", "-jar", "/springboot-web.jar"]
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4. 构建基础镜像, 上传到自己的镜像仓库。

docker build -t springboot-web:v1 .
# 运行镜像
docker run -it springboot-web:v1
docker tag springboot-web:v1 192.168.242.130/k8s/springboot-web:v1
docker push 192.168.242.130/k8s/springboot-web:v1
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5. 制作k8s服务并调度。springboot-web.yaml

# deploy
apiVersion: apps/v1
kind: Deployment
metadata:
  name: springboot-web-demo
spec:
  selector:
    matchLabels:
      app: springboot-web-demo
  replicas: 1
  template:
    metadata:
      labels:
        app: springboot-web-demo
    spec:
      containers:
      - name: springboot-web-demo
        image: 192.168.242.130/k8s/springboot-web:v1
        ports:
        - containerPort: 8080
---
# service
apiVersion: v1
kind: Service
metadata:
  name: springboot-web-demo
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 8080
  selector:
    app: springboot-web-demo
  type: ClusterIP

---
# ingress
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  name: springboot-web-demo
  annotations:
    # use the shared ingress-nginx
    kubernetes.io/ingress.class: "nginx"
spec:
  rules:
  - host: springboot.mooc.com
    http:
      paths:
      - path: /
        backend:
          serviceName: springboot-web-demo
          servicePort: 80
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6. k8s调度观察。

kubectl create -f springboot-web.yaml
# 查看运行的执行机
kubectl get pods -o wide
# 修改本机host 192.168.242.131 springboot.mooc.com
springboot.mooc.com/hello?name=Michael
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第三节 传统dubbo服务迁移K8s

1. 构建镜像

# 首先启动一个docker容器挂载zookeeper，提供服务注册与发现
docker pull zookeeper:3.4.10
docker run --name zoo-server --restart always -p 2181:2181 -d zookeeper:3.4.10
# 修改zookeeper注册地址 容器所在ip用来解析
dubbo.registry.address=zookeeper://192.168.242.130:2181
cd dubbo-demo-api
mvn install
cd dubbo-demo 
mvn package
# 查看具体内容 并解压
tar -tf dubbo-demo-1.0-SNAPSHOT-assembly.tar.gz 
tar -zvxf dubbo-demo-1.0-SNAPSHOT-assembly.tar.gz

# 进入bin目录并启动
sh start.sh
# 查看启动日志
cd logs && cat stdout.log
# 查看项目是否启动
netstat -ntlp | grep 20880

telnet localhost 20880
# telnet下操作 调用函数
ls
invoke com.mooc.demo.api.DemoService.sayHello("Dick")
# 停止命令
sh stop.sh
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2. 编写Dockerfile

mkdir ROOT
mv dubbo-demo-1.0-SNAPSHOT-assembly.tar.gz ROOT
tar -zvxf dubbo-demo-1.0-SNAPSHOT-assembly.tar.gz
rm -rf dubbo-demo-1.0-SNAPSHOT-assembly.tar.gz
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FROM openjdk:8-jre-alpine
COPY target/ROOT /ROOT
ENTRYPOINT ["sh", "/ROOT/bin/start.sh"]
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3. 构建基础镜像, 上传到自己的镜像仓库。

# 修改start.sh脚本 去掉nohup 让它不以后台方式运行和后面的重定向
# 删除下面检查进程的语句
PIDS=`ps  --no-heading -C java -f --width 1000 | grep "${CONF_DIR}" |awk '{print $2}'`
if [ -n "${PIDS}" ]; then
    echo "ERROR: The ${SERVER_NAME} already started!"
    echo "PID: ${PIDS}"
    exit 1
fi
cd target/ROOT/bin
docker build -t dubbo:v1 .
docker run -it dubbo:v1 .
docker tag dubbo:v1 192.168.242.130/k8s/dubbo:v1
docker push 192.168.242.130/k8s/dubbo:v1
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4. dubbo的服务发现在各个公司中也比较麻烦因为它有一个zookeeper。如果选用桥接模式的话。consumer从zookeeper获取服务提供者的信息。这里服务提供者是docker的容器。如果consumer也是集群内部没问题，如果在集群外部一定访问不到。
   • 可以选择在宿主机上写一个文件，包含主机ip。挂载容器里，这样也可以取到ip
   • 比较麻烦，而且性能不好
5. 确定服务发现策略。，最后选择host的模式。
   • 需要在主机上开一个20880的端口，它有个问题，要防止其他的dubbo服务端口冲突
   • 统一规划端口保证端口不冲突。可以在start.sh中加上自定义dubbo端口。

if [ -z "${DUBBO_PORT}" ]; then
	sed -i "s/dubbo.protocol.port=${SERVER_PORT}/dubbo.protocol.port=${DUBBO_PORT}/g" conf/dubbo.properties
	SERVER_PORT=${DUBBO_PORT}
fi

# 重新生成镜像
docker build -t dubbo:v1 .
docker run -it dubbo:v1 .
docker tag dubbo:v1 192.168.242.130/k8s/dubbo:v1
docker push 192.168.242.130/k8s/dubbo:v1
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6. 编写dubbo.yaml

#deploy
apiVersion: apps/v1
kind: Deployment
metadata:
  name: dubb-demo
spec:
  selector:
    matchLabels:
      app: dubb-demo
  replicas: 1
  template:
    metadata:
      labels:
        app: dubb-demo
    spec:
      hostNetwork: true
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchExpressions:
              - key: app
                operator: In
                values:
                - dubb-demo
            topologyKey: "kubernetes.io/hostname"
      containers:
      - name: dubb-demo
        image: 192.168.242.130/k8s/dubbo:v1
        ports:
        - containerPort: 20881
		# 这里通过环境变量 指定端口号
        env:
        - name: DUBBO_PORT
          value: "20881"
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7. 运行并测试服务。

netstat -ntlp | grep 20881
telnet localhost 20881
ls
invoke com.mooc.demo.api.DemoService.sayHello("Dick")
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第四节 传统web服务迁移K8s

1. 下载基础镜像, 配置

docker pull tomcat:8.0.51-alpine
docker tag  tomcat:8.0.51-alpine 192.168.242.130/k8s/tomcat:8.0.51-alpine
docker push  192.168.242.130/k8s/tomcat:8.0.51-alpine
# /web-demo/src/main/resources/applicationContext-service-config.xml 修改zookeeper地址
mvn package
mkdir ROOT
mv web-demo-1.0-SNAPSHOT.war ROOT
jar -xvf web-demo-1.0-SNAPSHOT.war
rm -rf web-demo-1.0-SNAPSHOT.war
# 运行一个镜像 查看ROOT所在目录
docker run -it --entrypoint bash tomcat:8.0.51-alpine
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2. 构建镜像

FROM tomcat:8.0.51-alpine
COPY target/ROOT /usr/local/tomcat/webapps/ROOT
COPY dockerfiles/start.sh /usr/local/tomcat/bin/start.sh
ENTRYPOINT ["sh" , "/usr/local/tomcat/bin/start.sh"]
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docker build -t web:v1 .
docker run -it web:v1 .
docker tag web:v1 192.168.242.130/k8s/web:v1
docker push 192.168.242.130/k8s/web:v1
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3. 确定服务发现策略编写k8s配置。和之前ingress-demo服务发现一样。

# deploy
apiVersion: apps/v1
kind: Deployment
metadata:
  name: web-demo
spec:
  selector:
    matchLabels:
      app: web-demo
  replicas: 1
  template:
    metadata:
      labels:
        app: web-demo
    spec:
      containers:
      - name: web-demo
        image: 192.168.242.130/k8s/web:v1
        ports:
        - containerPort: 8080
---
#service
apiVersion: v1
kind: Service
metadata:
  name: web-demo
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 8080
  selector:
    app: web-demo
  type: ClusterIP

---
#ingress
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: web-demo
spec:
  rules:
  - host: web.mooc.com
    http:
      paths:
      - path: /
        backend:
          serviceName: web-demo
          servicePort: 80
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4. 测试

# 修改hosts文件
192.168.242.131  web.mooc.com
web.mooc.com/hello?name="小姐姐"
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