centos7 安装 hadoop2.8.1

1，查看操作系统版本

    [hadoop@vm172-31-64-34 ~]$ cat /etc/centos-release

    CentOS Linux release 7.0.1406 (Core)

2，主机规划

    172.31.64.33  master

    172.31.64.34  slave1

    172.31.64.12  slave2

3，创建hadoop用户

    登录各主机，执行

    useradd hadoop

    passwd hadoop

4，免密登录

    在master上执行

    ssh-keygen 

    一路回车

    ssh-copy-id hadoop@172.31.64.34

    ssh-copy-id hadoop@172.31.64.12

5，java安装

    登录个主机执行

    yum install java

    查看openjdk安装路径

    [root@vm172-31-64-34 ~]# rpm -qa | grep openjdk

    java-1.8.0-openjdk-headless-1.8.0.151-5.b12.el7_4.x86_64

    java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64

    [root@vm172-31-64-34 ~]# rpm -ql java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64

    /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64/jre/bin/policytool

    /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64/jre/lib/amd64/libawt_xawt.so

    /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64/jre/lib/amd64/libjawt.so

    /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64/jre/lib/amd64/libjsoundalsa.so

    /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64/jre/lib/amd64/libsplashscreen.so

    /usr/share/applications/java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64-policytool.desktop

    配置环境变量

    export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64

    export JRE_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.151-5.b12.el7_4.x86_64/jre

    export CLASSPATH=.:${CLASSPATH}:${JAVA_HOME}/lib:${JRE_HOME}/lib

    export PATH=${PATH}:${JAVA_HOME}/bin:${JRE_HOME}/bin