Flink on Volcano

最近更新于 Jul 31, 2021

Flink简介

Apache Flink是由Apache软件基金会开发的开源流处理框架，其核心是用Java和Scala编写的分布式流数据流引擎。Flink以数据并行和流水线方式执行任意流数据程序，Flink的流水线运行时系统可以执行批处理和流处理程序。此外，Flink的运行时本身也支持迭代算法的执行。

前提条件

需要已经部署创建好CCE集群，集群下至少有一个可用节点，集群内节点已经绑定了弹性公网IP、kubectl命令行工具。

部署流程[1]

1.Download

为了运行Flink，需要java8或11的环境，使用如下的指令确定java的版本。

java -version

下载软件包并且进入目录下。

$ wget https://www.apache.org/dyn/closer.lua/flink/flink-1.12.2/flink-1.12.2-src.tgz
$ cd flink-1.12.2

2.Start a Cluster

运行脚本完成flink在集群上的部署。

$ ./bin/start-cluster.sh

3.Submit a job

随后可以使用如下的指令提交作业。

$ ./bin/flink run examples/streaming/WordCount.jar
$ tail log/flink-*-taskexecutor-*.out

Flink on Volcano[2]

1.部署组件

Flink cluster的部署需要创建两个deploy、一个service和一个configmap。调度策略采用volcano。flink-configuration-configmap.yaml内容如下

apiVersion: v1
kind: ConfigMap
metadata:
  name: flink-config
  labels:
    app: flink
data:
  flink-conf.yaml: |+
    jobmanager.rpc.address: flink-jobmanager
    taskmanager.numberOfTaskSlots: 2
    blob.server.port: 6124
    jobmanager.rpc.port: 6123
    taskmanager.rpc.port: 6122
    queryable-state.proxy.ports: 6125
    jobmanager.memory.process.size: 1600m
    taskmanager.memory.process.size: 1728m
    parallelism.default: 2
  log4j-console.properties: |+
    # This affects logging for both user code and Flink
    rootLogger.level = INFO
    rootLogger.appenderRef.console.ref = ConsoleAppender
    rootLogger.appenderRef.rolling.ref = RollingFileAppender
    # Uncomment this if you want to _only_ change Flink's logging
    #logger.flink.name = org.apache.flink
    #logger.flink.level = INFO
    # The following lines keep the log level of common libraries/connectors on
    # log level INFO. The root logger does not override this. You have to manually
    # change the log levels here.
    logger.akka.name = akka
    logger.akka.level = INFO
    logger.kafka.name= org.apache.kafka
    logger.kafka.level = INFO
    logger.hadoop.name = org.apache.hadoop
    logger.hadoop.level = INFO
    logger.zookeeper.name = org.apache.zookeeper
    logger.zookeeper.level = INFO
    # Log all infos to the console
    appender.console.name = ConsoleAppender
    appender.console.type = CONSOLE
    appender.console.layout.type = PatternLayout
    appender.console.layout.pattern = %d{yyyy-MM-dd HH:mm:ss,SSS} %-5p %-60c %x - %m%n
    # Log all infos in the given rolling file
    appender.rolling.name = RollingFileAppender
    appender.rolling.type = RollingFile
    appender.rolling.append = false
    appender.rolling.fileName = ${sys:log.file}
    appender.rolling.filePattern = ${sys:log.file}.%i
    appender.rolling.layout.type = PatternLayout
    appender.rolling.layout.pattern = %d{yyyy-MM-dd HH:mm:ss,SSS} %-5p %-60c %x - %m%n
    appender.rolling.policies.type = Policies
    appender.rolling.policies.size.type = SizeBasedTriggeringPolicy
    appender.rolling.policies.size.size=100MB
    appender.rolling.strategy.type = DefaultRolloverStrategy
    appender.rolling.strategy.max = 10
    # Suppress the irrelevant (wrong) warnings from the Netty channel handler
    logger.netty.name = org.apache.flink.shaded.akka.org.jboss.netty.channel.DefaultChannelPipeline
    logger.netty.level = OFF

service用来提供JobManager的REST和UI端口的服务，jobmanager-service.yaml内容如下

apiVersion: v1
kind: Service
metadata:
  name: flink-jobmanager
spec:
  type: ClusterIP
  ports:
  - name: rpc
    port: 6123
  - name: blob-server
    port: 6124
  - name: webui
    port: 8081
  selector:
    app: flink
    component: jobmanager

jobmanager-session-deployment.yaml内容如下

apiVersion: apps/v1
kind: Deployment
metadata:
  name: flink-jobmanager
spec:
  replicas: 1
  selector:
    matchLabels:
      app: flink
      component: jobmanager
  template:
    metadata:
      labels:
        app: flink
        component: jobmanager
    spec:
      containers:
      - name: jobmanager
        image: flink:1.11.0-scala_2.11
        args: ["jobmanager"]
        ports:
        - containerPort: 6123
          name: rpc
        - containerPort: 6124
          name: blob-server
        - containerPort: 8081
          name: webui
        livenessProbe:
          tcpSocket:
            port: 6123
          initialDelaySeconds: 30
          periodSeconds: 60
        volumeMounts:
        - name: flink-config-volume
          mountPath: /opt/flink/conf
        securityContext:
          runAsUser: 9999  # refers to user _flink_ from official flink image, change if necessary
      volumes:
      - name: flink-config-volume
        configMap:
          name: flink-config
          items:
          - key: flink-conf.yaml
            path: flink-conf.yaml
          - key: log4j-console.properties
            path: log4j-console.properties

taskmanager-session-deployment.yaml内容如下

apiVersion: apps/v1
kind: Deployment
metadata:
  name: flink-taskmanager
spec:
  replicas: 2
  selector:
    matchLabels:
      app: flink
      component: taskmanager
  template:
    metadata:
      labels:
        app: flink
        component: taskmanager
    spec:
      containers:
      - name: taskmanager
        image: flink:1.11.0-scala_2.11
        args: ["taskmanager"]
        ports:
        - containerPort: 6122
          name: rpc
        - containerPort: 6125
          name: query-state
        livenessProbe:
          tcpSocket:
            port: 6122
          initialDelaySeconds: 30
          periodSeconds: 60
        volumeMounts:
        - name: flink-config-volume
          mountPath: /opt/flink/conf/
        securityContext:
          runAsUser: 9999  # refers to user _flink_ from official flink image, change if necessary
      volumes:
      - name: flink-config-volume
        configMap:
          name: flink-config
          items:
          - key: flink-conf.yaml
            path: flink-conf.yaml
          - key: log4j-console.properties
            path: log4j-console.properties

在集群节点创建好上面四个yaml配置文件，使用如下指令进行部署。

kubectl create -f flink-configuration-configmap.yaml
kubectl create -f jobmanager-service.yaml
kubectl create -f jobmanager-session-deployment.yaml
kubectl create -f taskmanager-session-deployment.yaml

创建成功后查询：

kubectl get cm| grep flink
kubectl get svc | grep flink
kubectl get pod -owide | grep Flink

2.对外发布服务[3]

创建好flink负载之后，需要像外部发布服务。

• 若使用华为云CCE进行测试，进入CCE的”工作负载-无状态负载”页面。选择flink-jobmanager，单击”访问方式”。
• 点击“添加service”，选择节点访问，输入容器端口位8081。
• 点击CCE中的网络管理，能够看到刚才我们添加的service，访问对外发布的链接。
• 进入flink的Dashboard页面，点击submit new job提交任务官方的WordCount作业。目录为flink-1.12.2/examples/streaming/WordCount.jar。