基于Docker快速搭建Hadoop集群和Flink运行环境

1. 前言
2. 搭建集群
3. 环境升级
4. 配置Hadoop
5. 配置Flink
6. 打包镜像
7. 启动集群

---

前言

本文主要讲，基于Docker在本地快速搭建一个Hadoop 2.7.2集群和Flink 1.11.2运行环境，用于日常Flink任务运行测试。
前任栽树，后人乘凉，我们直接用Docker Hadoop镜像kiwenlau/hadoop-cluster-docker来搭建，这个镜像内已经配置部署好了Hadoop 2.7.2，感谢前辈们造好轮子。

该Docker Hadoop镜像优点：基于Docker快速搭建多节点Hadoop集群

我们要搭建一个3节点的Hadoop集群，集群架构如下图，一个主节点hadoop-master，两个数据节点hadoop-slave1和hadoop-slave2。每个Hadoop节点运行在一个Docker容器中，容器之间互相连通，构成一个Hadoop集群。

还不熟悉Docker的可以参见：菜鸟教程-Docker教程
搭建过程部分搬运自镜像作者教程：基于Docker搭建Hadoop集群之升级版

搭建集群

1.下载Docker镜像

sudo docker pull kiwenlau/hadoop:1.0

2.下载GitHub仓库

git clone https://github.com/kiwenlau/hadoop-cluster-docker

3.创建Hadoop网络

sudo docker network create --driver=bridge hadoop

4.运行Docker容器

cd hadoop-cluster-docker
./start-container.sh

运行结果

start hadoop-master container...
start hadoop-slave1 container...
start hadoop-slave2 container...
root@hadoop-master:~#

启动了3个容器，1个master, 2个slave
运行后就进入了hadoop-master容器的/root目录，我们在目录下新建一个自己的文件夹shadow
这时候不要着急启动Hadoop集群，我们先升级一下环境配置

环境升级

1.更新包

apt-get update
apt-get install vim

2.升级JDK
将JDK 1.7升级到JDK 1.8，先去官网下载一个JDK 1.8：jdk-8u261-linux-x64.tar.gz

从本地拷贝JDK 1.8到Docker容器hadoop-master

docker cp jdk-8u261-linux-x64.tar.gz hadoop-master:/root/shadow

解压升级

tar -zxvf jdk-8u261-linux-x64.tar.gz

sudo update-alternatives --install /usr/bin/java java /root/shadow/jdk1.8.0_261/bin/java 300
sudo update-alternatives --config java

sudo update-alternatives --install /usr/bin/javac javac /root/shadow/jdk1.8.0_261/bin/javac 300
sudo update-alternatives --config javac

java -version
javac -version

卸载JDK1.7：删除JDK1.7的目录即可

3.配置环境变量

vi ~/.bashrc
export HADOOP_HOME=/usr/local/hadoop
export HADOOP_CLASSPATH=$($HADOOP_HOME/bin/hadoop classpath)
export JAVA_HOME=/root/shadow/jdk1.8.0_261
export JAVA=/root/shadow/jdk1.8.0_261/bin/java
export PATH=$JAVA_HOME/bin:$PATH
export CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$CLASS_PATH:$HADOOP_CLASSPATH
source ~/.bashrc

4.修改集群启动脚本

vi start-hadoop.sh
关闭Hadoop安全模式，末尾加上：hadoop dfsadmin -safemode leave

配置Hadoop

修改Hadoop配置，Hadoop配置路径：/usr/local/hadoop/etc/hadoop

core-site.xml

<configuration>
    <property>
        <name>fs.defaultFSname>
        <value>hdfs://hadoop-master:9000/value>
    property>
    <property>
        <name>hadoop.tmp.dirname>
        <value>/usr/local/hadoop/tmpvalue>
    property>
    <property>
        <name>dfs.journalnode.edits.dirname>
        <value>/usr/local/hadoop/journalvalue>
    property>
configuration>

yarn-site.xml

<configuration>
    <property>
        <name>yarn.nodemanager.aux-servicesname>
        <value>mapreduce_shufflevalue>
    property>
    <property>
        <name>yarn.nodemanager.aux-services.mapreduce_shuffle.classname>
        <value>org.apache.hadoop.mapred.ShuffleHandlervalue>
    property>
    <property>
        <name>yarn.resourcemanager.hostnamename>
        <value>hadoop-mastervalue>
    property>
    <property>
        <name>yarn.nodemanager.resource.memory-mbname>
        <value>1024value>
    property>
    <property>
        <name>yarn.scheduler.minimum-allocation-mbname>
        <value>1024value>
    property>
    <property>
        <name>yarn.scheduler.maximum-allocation-mbname>
        <value>1024value>
    property>
    <property>
        <name>yarn.nodemanager.vmem-check-enabledname>
        <value>falsevalue>
    property>
    <property>
        <name>yarn.log-aggregation-enablename>
        <value>truevalue>
    property>
    <property>
        <name>yarn.nodemanager.log-aggregation.roll-monitoring-interval-secondsname>
        <value>3600value>
    property>
    <property>
        <name>yarn.nodemanager.remote-app-log-dirname>
        <value>/tmp/logsvalue>
    property>
configuration>

hdfs-site.xml

<configuration>
    <property>
        <name>dfs.namenode.name.dirname>
        <value>file:///root/hdfs/namenodevalue>
        <description>NameNode directory for namespace and transaction logs storage.description>
    property>
    <property>
        <name>dfs.datanode.data.dirname>
        <value>file:///root/hdfs/datanodevalue>
        <description>DataNode directorydescription>
    property>
    <property>
        <name>dfs.replicationname>
        <value>2value>
    property>
    <property>
        <name>dfs.permissionsname>
        <value>falsevalue>
    property>
    <property>
        <name>dfs.safemode.threshold.pctname>
        <value>1value>
    property>
    <property>
        <name>dfs.client.use.datanode.hostnamename>
        <value>truevalue>
    property>
    <property>
        <name>dfs.datanode.use.datanode.hostnamename>
        <value>truevalue>
    property>
configuration>

配置Flink

1.Flink官网下载：Flink 1.11.2

2.从本地拷贝JDK 1.8到Docker容器hadoop-master

docker cp flink-1.11.2-bin-scala_2.11.tgz hadoop-master:/root/shadow

3.修改Flink配置

tar -zxvf flink-1.11.2-bin-scala_2.11.tgz
cd flink-1.11.2/conf/
vi flink-conf.yaml 

flink-conf.yaml

jobmanager.rpc.address: hadoop-master
jobmanager.memory.process.size: 1024m
taskmanager.memory.process.size: 1024m
taskmanager.numberOfTaskSlots: 2
parallelism.default: 2

打包镜像

1.将刚刚配置好的容器hadoop-master打包成新的镜像

docker commit -m="Hadoop&Flink" -a="shadow" fd5163c5baac kiwenlau/hadoop:1.1

2.删除正在运行的容器

cd hadoop-cluster-docker
./rm-container.sh

3.修改启动脚本，将镜像版本改为1.1

vi start-container.sh

start-container.sh

#!/bin/bash

# the default node number is 3
N=${1:-3}


# start hadoop master container
sudo docker rm -f hadoop-master &> /dev/null
echo "start hadoop-master container..."
sudo docker run -itd \
                --net=hadoop \
                -p 50070:50070 \
                -p 8088:8088 \
		-p 8032:8032 \
		-p 9000:9000 \
                --name hadoop-master \
                --hostname hadoop-master \
                kiwenlau/hadoop:1.1 &> /dev/null


# start hadoop slave container
i=1
while [ $i -lt $N ]
do
	sudo docker rm -f hadoop-slave$i &> /dev/null
	echo "start hadoop-slave$i container..."
	sudo docker run -itd \
	                --net=hadoop \
	                --name hadoop-slave$i \
	                --hostname hadoop-slave$i \
	                kiwenlau/hadoop:1.1 &> /dev/null
	i=$(( $i + 1 ))
done 

# get into hadoop master container
sudo docker exec -it hadoop-master bash

启动集群

1.运行Docker容器

./start-container.sh

运行后就进入了hadoop-master容器的/root目录

2.启动Hadoop集群

./start-hadoop.sh

打开本机浏览器，查看已经启动的Hadoop集群：Hadoop集群
查看集群概况：集群概况

然后就可以愉快的在Docker Hadoop集群中测试Flink任务了！