Hadoop学习环境搭建
- Apache Hadoop3.1.1虚拟机环境搭建
- 工具准备
- 安装虚拟机
- Hadoop安装和配置
- 配置Hadoop001、Hadoop002、Hadoop003互相访问
- 配置Hadoop
- 启动Hadoop
Apache Hadoop3.1.1虚拟机环境搭建
最近想学习一下大数据相关的知识,都说Hadoop是目前学习大数据必不可少的,所以那就先从Hadoop开始吧。第一步就是搭建一个Hadoop的环境,我选择的是用VirtualBox虚拟机搭建一个简单的Hadoop环境,Hadoop的版本是3.1.1。
工具准备
- 虚拟机工具:VIrtualBox
- 操作系统:CentOS7.5
- Hadoop-3.1.1
安装虚拟机
利用VirtualBox搭建虚拟机环境,一共安装三台虚拟机,一台作为namenode,两台作为datanode,三台虚拟机只有hostname和ip不同,其他相同,所以只演示一台的安装过程:
- 新建虚拟机,名称为hadoop001,操作系统选择Linux,版本选择Red Hat (64-bit),点击【下一步】 ;
- 设置内存和硬盘保存位置及大小,我是设置的2G内存和100G硬盘;
- 创建完成后,设置存储为下载的CentOS安装ISO文件,设置网络为桥接网卡,然后点击启动,开始安装操作系统;
- 安装操作系统不多赘述,正常安装即可,需要注意一点,安装过程中直接设置好hostname和IP地址;
- hadoop001安装完成,,hostname:hadoop001,ip:192.168.0.181。由于安装的是Minal模式,所以需要通过yum安装net-tools等工具。具体工具可百度。同时需要安装Java环境,简单说来就是下载jdk,然后解压到指定目录后,设置环境变量即可,此处不再具体叙述 ,可百度。连接linux和传输文件的工具可以用XShell和XFtp。
# Java environment
export JAVA_HOME=/usr/lib/java/jdk1.8.0_181
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/jre/lib/rt.jar:${JAVA_HOME}/lib/dt.jar:${JAVA_HOME}/lib/tools.jar
export PATH=$PATH:${JAVA_HOME}/bin
- 按照hadoop001的方式安装完成hadoop002(hostname:hadoop002, ip:192.168.0.182),hadoop003(hostname:hadoop003, ip:192.168.0.183);此处的IP地址根据你自己的网络环境进行设置。按照hadoop001的方式安装完成hadoop002(hostname:hadoop002, ip:192.168.0.182),hadoop003(hostname:hadoop003, ip:192.168.0.183);此处的IP地址根据你自己的网络环境进行设置。
到此为止,虚拟机环境安装完成,接下来就是Hadoop的安装和配置过程
Hadoop安装和配置
- 第一步配置三台虚拟机之间能互相不用用户名密码访问
- 配置Hadoop
- 启动Hadoop
配置Hadoop001、Hadoop002、Hadoop003互相访问
- 虚拟机中设置host文件
vim /etc/hosts
三台机器做一样的设置
192.168.0.181 hadoop001
192.168.0.182 hadoop002
192.168.0.183 hadoop003
保证三台机器都能互相ping通
- 虚拟机hadoop001中生成ssh密钥
ssh-keygen -t rsa -P ''
hadoop002与hadoop003做同样的操作,完成后可以通过命令查看密钥对是否生成成功
ls /root/.ssh/
然后合并hadoop001、hadoop002、hadoop003的id_rsa.pub文件内容到authorized_keys文件中:
首先看一下三台机器中的id_rsa.pub内容
hadoop001
cat ~/.ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC4X22DpQ8VYtLZsz0bmd8M4DvU6Ixf6YuZ1ss7Y+gJPIL4X/X2bYIk14rRTPY3/N2lG758mh0OJL0ET1c4J+48g/YZ3gXvbeo4WxIfNaVF/5Qk64hTQjrDpT8BmOB0U/rzt3TDndnkKiOLuHsbaCSthkCZEN2Hrn1IcLVYIj5BxlS5Gtb3eFhKElNfFoFsnoIulMirxuqOld0UhSYNNBOcnZoTll/GUdHufDorlR0ADwM1AxbVo4uVPnDk4i1heVEXyL5iySxM5+Z+qYqywGyKHCBNEIBx0TpnCqnBofv0fd+pDNDbNHYbulAMLZbio85WlsSzhpL5Wws8M3LcGWFD root@hadoop001
hadoop002
cat ~/.ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC0MB7PUJYdVwEr9fKgJ1b8xaODbq4ZX0G/+YrLEj6e6/TNHo/M6U/bEPWkClT14PjI2SKXqVtHgMLDe8aShxHxV7KfXG6KS002lIGXa0bOXdbFIr74GEdJJmL1wLZvbuKEAC8h1DkIsnDLr7/pKTDReN3L1iHgcSqjUHXqXC0cd6tZTfc/oDqZ7q2xmGbdRSB/uKX1stt09+a64AAvQPrCenTS6BP4VfSnY2WCxUOu28+z33uZf2q4UxwIdYn1CmPGCeobdeLyfeMMrVZoJfhE/K47wiAUteb+bHvpsy9pS5beJjBcI0Cvri0puH4HgOoveMNhenBMVGS68Lo5fr8h root@hadoop002
hadoop003
cat ~/.ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDJ3BgltB9uS8oRxoIrHwBsUOwSak2eKF7SqjKD6uacXc5iE6uXvSiZxT8BKhPHczBWQ2s2vd40U616L9SlHbN2rzsED6AdM9zNPvcPEW/SgmC2yJ4HYAJJKo+UAYLHwj9nh5IocwbHTkIxTAmBubvXcKOvjyzB2NMK4T0VAuEvLadySrxCt/cyHBGT0V0h2RAyx0IODSL5+gP/mNJsoou1wq2H18XF2TNYTUZU2aMb4HW99mcCm7Ps451LcGVSHKxoWyr08FaKZyV0vqI2va33JhohzxW7bhHbAsWK1UJE9jWhKbIL1Flmi6TS9mlnFVytoCHc+LU/AKtOS+ZonGx5 root@hadoop003
首先创建authorized_keys文件,然后添加hadoop001中的id_rsa.pub中的内容
touch authorized_keys
cat id_rsa.pub >> authorized_keys
通过xshell工具可以非常方便的通过vim命令编辑authorized_keys文件,把hadoop002和hadoop003的id_rsa.pub文件内容合并到authorized_keys中。
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC4X22DpQ8VYtLZsz0bmd8M4DvU6Ixf6YuZ1ss7Y+gJPIL4X/X2bYIk14rRTPY3/N2lG758mh0OJL0ET1c4J+48g/YZ3gXvbeo4WxIfNaVF/5Qk64hTQjrDpT8BmOB0U/rzt3TDndnkKiOLuHsbaCSthkCZEN2Hrn1IcLVYIj5BxlS5Gtb3eFhKElNfFoFsnoIulMirxuqOld0UhSYNNBOcnZoTll/GUdHufDorlR0ADwM1AxbVo4uVPnDk4i1heVEXyL5iySxM5+Z+qYqywGyKHCBNEIBx0TpnCqnBofv0fd+pDNDbNHYbulAMLZbio85WlsSzhpL5Wws8M3LcGWFD root@hadoop001
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC0MB7PUJYdVwEr9fKgJ1b8xaODbq4ZX0G/+YrLEj6e6/TNHo/M6U/bEPWkClT14PjI2SKXqVtHgMLDe8aShxHxV7KfXG6KS002lIGXa0bOXdbFIr74GEdJJmL1wLZvbuKEAC8h1DkIsnDLr7/pKTDReN3L1iHgcSqjUHXqXC0cd6tZTfc/oDqZ7q2xmGbdRSB/uKX1stt09+a64AAvQPrCenTS6BP4VfSnY2WCxUOu28+z33uZf2q4UxwIdYn1CmPGCeobdeLyfeMMrVZoJfhE/K47wiAUteb+bHvpsy9pS5beJjBcI0Cvri0puH4HgOoveMNhenBMVGS68Lo5fr8h root@hadoop002
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDJ3BgltB9uS8oRxoIrHwBsUOwSak2eKF7SqjKD6uacXc5iE6uXvSiZxT8BKhPHczBWQ2s2vd40U616L9SlHbN2rzsED6AdM9zNPvcPEW/SgmC2yJ4HYAJJKo+UAYLHwj9nh5IocwbHTkIxTAmBubvXcKOvjyzB2NMK4T0VAuEvLadySrxCt/cyHBGT0V0h2RAyx0IODSL5+gP/mNJsoou1wq2H18XF2TNYTUZU2aMb4HW99mcCm7Ps451LcGVSHKxoWyr08FaKZyV0vqI2va33JhohzxW7bhHbAsWK1UJE9jWhKbIL1Flmi6TS9mlnFVytoCHc+LU/AKtOS+ZonGx5 root@hadoop003
然后通过xftp工具非常方便的把该文件放到hadoop002和hadoop003中的相同路径下
现在就可测试看看ssh无密码登录了,从hadoop001上分别通过ssh直接连接hadoop002和hadoop003,发现无需输入密码可直接登录
配置Hadoop
- 关闭防火墙
为了防止防火墙原因导致节点之间通信出现问题,首先关闭防火墙并重启,命令如下,在三台虚拟机中分别进行操作
#执行以下命令关闭防火墙
[root@hadoop001 ~]systemctl stop firewalld && systemctl disable firewalld
[root@hadoop001 ~]setenforce 0
#将SELINUX的值改成disabled
[root@hadoop001 ~]vim /etc/selinux/config
SELINUX=disabled
#重启服务器
[root@hadoop001 ~]reboot
- 配置文件修改
首先通过xftp工具把下载的hadoop文件传到虚拟机中,然后解压后,设置环境变量,我的环境变量如下,通过命令vim /etc/profile 编辑配置文件,在文件最后添加以下内容。具体路径各位可根据自己的具体情况设置
# Hadoop environment
export HADOOP_HOME=/opt/hadoop/hadoop-3.1.1
export PATH=$PATH:${HADOOP_HOME}/bin
完成后通过source命令刷新环境变量,切记
定位到hadoop目录下,然后配置hadoop的配置文件,这些配置文件全部位于 /opt/hadoop/hadoop-3.1.1/etc/hadoop 文件夹下
hadoop-env.sh
# The java implementation to use. By default, this environment
# variable is REQUIRED on ALL platforms except OS X!
# export JAVA_HOME=
export JAVA_HOME=/usr/lib/java/jdk1.8.0_181
core-site.xml
<configuration>
<!-- 指定HDFS老大(namenode)的通信地址 -->
<property>
<name>fs.defaultFS</name>
<value>hdfs://hadoop001:9000</value>
</property>
<!-- 指定hadoop运行时产生文件的存储路径 -->
<property>
<name>hadoop.tmp.dir</name>
<value>/opt/hadoop/data/tmp</value>
</property>
</configuration>
hdfs-site.xml
<configuration>
<!-- 设置namenode的http通讯地址 -->
<property>
<name>dfs.namenode.http-address</name>
<value>hadoop001:50070</value>
</property>
<!-- 设置secondarynamenode的http通讯地址 -->
<property>
<name>dfs.namenode.secondary.http-address</name>
<value>hadoop002:50090</value>
</property>
<!-- 设置namenode存放的路径 -->
<property>
<name>dfs.namenode.name.dir</name>
<value>/opt/hadoop/data/name</value>
</property>
<!-- 设置hdfs副本数量 -->
<property>
<name>dfs.replication</name>
<value>2</value>
</property>
<!-- 设置datanode存放的路径 -->
<property>
<name>dfs.datanode.data.dir</name>
<value>/opt/hadoop/data/datanode</value>
</property>
<property>
<name>dfs.permissions</name>
<value>false</value>
</property>
</configuration>
mapred-site.xml
<configuration>
<!-- 通知框架MR使用YARN -->
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>
<property>
<name>mapreduce.application.classpath</name>
<value>
/opt/hadoop/hadoop-3.1.1/etc/hadoop,
/opt/hadoop/hadoop-3.1.1/share/hadoop/common/*,
/opt/hadoop/hadoop-3.1.1/share/hadoop/common/lib/*,
/opt/hadoop/hadoop-3.1.1/share/hadoop/hdfs/*,
/opt/hadoop/hadoop-3.1.1/share/hadoop/hdfs/lib/*,
/opt/hadoop/hadoop-3.1.1/share/hadoop/mapreduce/*,
/opt/hadoop/hadoop-3.1.1/share/hadoop/mapreduce/lib/*,
/opt/hadoop/hadoop-3.1.1/share/hadoop/yarn/*,
/opt/hadoop/hadoop-3.1.1/share/hadoop/yarn/lib/*
</value>
</property>
</configuration>
yarn-site.xml
<configuration>
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
<property>
<name>yarn.nodemanager.aux-services.mapreduce.shuffle.class</name>
<value>org.apache.hadoop.mapred.ShuffleHandle</value>
</property>
<property>
<name>yarn.resourcemanager.resource-tracker.address</name>
<value>hadoop001:8025</value>
</property>
<property>
<name>yarn.resourcemanager.scheduler.address</name>
<value>hadoop001:8030</value>
</property>
<property>
<name>yarn.resourcemanager.address</name>
<value>hadoop001:8040</value>
</property>
</configuration>
$HADOOP_HOME/sbin/start-dfs.sh $HADOOP_HOME/sbin/stop-dfs.sh
HDFS_DATANODE_USER=root
HADOOP_SECURE_DN_USER=hdfs
HDFS_NAMENODE_USER=root
HDFS_SECONDARYNAMENODE_USER=root
$HADOOP_HOME/sbin/start-yarn.sh $HADOOP_HOME/sbin/stop-yarn.sh
YARN_RESOURCEMANAGER_USER=root
HADOOP_SECURE_DN_USER=yarn
YARN_NODEMANAGER_USER=root
masters
需要创建一个master文件,配置secondary namenode的主机
[root@hadoop001 hadoop]# touch /opt/hadoop/hadoop-3.1.1/etc/hadoop/masters
[root@hadoop001 hadoop]# vim /opt/hadoop/hadoop-3.1.1/etc/hadoop/masters
#添加
hadoop002
workers
[root@hadoop001 hadoop]# vim /opt/hadoop/hadoop-3.1.1/etc/hadoop/workers
#添加
hadoop002
hadoop003
创建文件夹
[root@hadoop001 hadoop]# mkdir -p /opt/hadoop/data/tmp
[root@hadoop001 hadoop]# mkdir -p /opt/hadoop/data/name
[root@hadoop001 hadoop]# mkdir -p /opt/hadoop/data/datanode
复制到其他主机
[root@hadoop001 opt]# scp -r /opt/hadoop hadoop002:/opt/
[root@hadoop001 opt]# scp -r /opt/hadoop hadoop003:/opt/
修改hadoop002、hadoop003 环境变量,修改完成后刷新环境变量
启动Hadoop
第一次启动需要格式化,然后运行脚本启动即可
[root@hadoop001 opt]# /opt/hadoop/hadoop-3.1.1/bin/hdfs namenode -format
[root@hadoop001 opt]# /opt/hadoop/hadoop-3.1.1/sbin/start-all.sh
启动后通过浏览器访问hadoop001上的站点地址,可以查看当前hadoop状态,到此为止环境搭建完成。