Hadoop集群环境搭建

1. 服务器ip列表配置信息

192.168.10.128 hufu01
192.168.10.129 hufu02
192.168.10.130 hufu03
192.168.10.131 hufu04

2. 每台服务器的硬件和操作系统信息

##查看当前操作系统版本信息 
[root@hufu02 ~]# cat /proc/version
Linux version 3.10.0-957.el7.x86_64 (mockbuild@kbuilder.bsys.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-36) (GCC) ) #1 SMP Thu Nov 8 23:39:32 UTC 2018

##查看版本当前操作系统内核信息
[root@hufu02 ~]# uname -a
Linux hufu02 3.10.0-957.el7.x86_64 #1 SMP Thu Nov 8 23:39:32 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

##查看版本当前操作系统发行信息
[root@hufu02 ~]# cat /etc/centos-release
CentOS Linux release 7.6.1810 (Core) 

3. 设置免密登录

## 生成密钥，在四台服务器上分别执行
[root@hufu01 ~]# ssh-keygen -t rsa（一路回车到底）

##复制密钥，在hufu01上执行
[root@hufu01 ~]# ssh-copy-id hufu02 （yes，输入密码）
[root@hufu01 ~]# ssh-copy-id hufu03 （yes，输入密码）
[root@hufu01 ~]# ssh-copy-id hufu04 （yes，输入密码）

## 测试是否成功：
[root@hufu01 ~]# ssh hufu02
Last login: Fri Aug 16 02:43:39 2019 from 192.168.10.1
[root@hufu02 ~]# exit
logout
Connection to hufu02 closed.
[root@hufu01 ~]# ssh hufu03
Last login: Fri Aug 16 00:47:27 2019 from 192.168.10.1
[root@hufu03 ~]# exit
logout
Connection to hufu03 closed.
[root@hufu01 ~]# ssh hufu04
Last login: Fri Aug 16 00:47:27 2019 from 192.168.10.1
[root@hufu04 ~]# exit
logout
Connection to hufu04 closed.
## 配置成功

4. 新增hadoop账号,并且配置免密登录

## 生成密钥，在四台服务器上分别执行
[root@hufu01 ~]# useradd hadoop
[root@hufu01 ~]# passwd hadoop
Changing password for user hadoop.
New password:  ##这里设置密码为hadoop
BAD PASSWORD: The password is shorter than 8 characters
Retype new password: 
passwd: all authentication tokens updated successfully.

##配置免密登录(先切换到hadoop用户，再去配置)，略去

5. 安装jdk

##1. 安装略去，jdk的路径和版本信息如下
[hadoop@hufu01 app]$ echo $JAVA_HOME
/app/jdk
[hadoop@hufu01 app]$ java -version
java version "1.8.0_221"
Java(TM) SE Runtime Environment (build 1.8.0_221-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.221-b11, mixed mode)
##2. 将hufu01上安装好的jdk 发送到 hufu02，hufu03，hufu04上

6.安装hadoop（在hadoop用户下）

6.1 解压 hadoop-2.7.7.tar.gz

[hadoop@hufu01 ~]$ tar hadoop-2.7.7.tar.gz -C /home/hadoop

6.2 配置hadoop

<!-- 1. core-site.xml -->
<configuration>　
    <property>　　　
        <name>fs.default.name</name>　　　
        <value>hdfs://hufu01:9000</value>　　
    </property>　
    <property>　　　
        <name>hadoop.tmp.dir</name>　　　
        <value>file:/home/hadoop/hadoop/tmp</value>　　
    </property>
    <property>
        <name>hadoop.proxyuser.hadoop.hosts</name>
        <value>*</value>
    </property>
    <property>
        <name>hadoop.proxyuser.hadoop.groups</name>
        <value>hadoop</value>
    </property>
</configuration>
<!-- 2. core-site.xml -->
<configuration>　
    <property>　　　　
        <name>dfs.replication</name>        　　　　
        <value>2</value>        　　
    </property>    　　
    <property>        　　　　
        <name>dfs.namenode.name.dir</name>        　　　　
        <value>file:/home/hadoop/hadoop/tmp/dfs/name</value>        　　
    </property>    　　
    <property>        　　　　
        <name>dfs.datanode.data.dir</name>        　　　　
        <value>file:/home/hadoop/hadoop/tmp/dfs/data</value>        　　
    </property>    　　
    <property>        　　　　
        <name>dfs.namenode.secondary.http-address</name>        　　　　
        <value>hufu01:9001</value>        　　
    </property>
</configuration>

<!-- 3. yarn-site.xml -->
<configuration>
    <!-- Site specific YARN configuration properties -->
　　<property>
　　　　<name>yarn.resourcemanager.hostname</name>
　　　　<value>hufu01</value>
　　</property>
　　<property>
　　　　<name>yarn.nodemanager.aux-services</name>
　　　　<value>mapreduce_shuffle</value>
　　</property>
　　<property>
　　　　<name>yarn.log-aggregation-enable</name>
　　　　<value>true</value>
　　</property>
　　<property>
　　　　<name>yarn.log-aggregation.retain-seconds</name>
　　　　<value>604800</value>
　　</property>
</configuration>
<!-- 4. mapred-site.xml -->
<configuration>
　　<property>
　　　　<name>mapreduce.framework.name</name>
　　　　<value>yarn</value>
　　</property>
</configuration>
<!-- 5. slaves -->
hufu02
hufu03
hufu04

6.3 修改hadoop依赖的jdk环境路径

[hadoop@hufu01 hadoop]$ vim hadoop-env.sh
24 # The java implementation to use.
25 export JAVA_HOME=/app/jdk

6.4 配置环境变量（两种配置：/etc/profile里面配置和 .bashrc里面配置）并使其生效

## 配置变量
[root@hufu01 hadoop]$ vim /etc/profile
#hadoop environment vars
export HADOOP_HOME=/home/hadoop/hadoop-2.7.7
export HADOOP_INSTALL=$HADOOP_HOME
export HADOOP_MAPRED_HOME=$HADOOP_HOME
export HADOOP_COMMON_HOME=$HADOOP_HOME
export HADOOP_HDFS_HOME=$HADOOP_HOME
export YARN_HOME=$HADOOP_HOME
export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_HOME/lib/native
export PATH=$PATH:$HADOOP_HOME/sbin:$HADOOP_HOME/bin
export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_HOME/lib/native  
export HADOOP_OPTS="-Djava.library.path=$HADOOP_HOME/lib/native"  

## 生效
[root@hufu01 hadoop]$ source /etc/profile

7.将修改好的hadoop和环境变量的文件发到hufu02，hufu03，hufu04,并关闭四台服务器的防火墙

8.格式化hdfs文件系统

hadoop namenode -format

9.启动

## 1.启动hdfs
[hadoop@hufu01 root]$ start-dfs.sh 
Starting namenodes on [hufu01]
hufu01: starting namenode, logging to /home/hadoop/hadoop-2.7.7/logs/hadoop-hadoop-namenode-hufu01.out
hufu04: starting datanode, logging to /home/hadoop/hadoop-2.7.7/logs/hadoop-hadoop-datanode-hufu04.out
hufu02: starting datanode, logging to /home/hadoop/hadoop-2.7.7/logs/hadoop-hadoop-datanode-hufu02.out
hufu03: starting datanode, logging to /home/hadoop/hadoop-2.7.7/logs/hadoop-hadoop-datanode-hufu03.out
Starting secondary namenodes [hufu01]
hufu01: starting secondarynamenode, logging to /home/hadoop/hadoop-2.7.7/logs/hadoop-hadoop-secondarynamenode-hufu01.out

##2. 启动yarn 
[hadoop@hufu01 root]$ start-yarn.sh 
starting yarn daemons
starting resourcemanager, logging to /home/hadoop/hadoop-2.7.7/logs/yarn-hadoop-resourcemanager-hufu01.out
hufu03: starting nodemanager, logging to /home/hadoop/hadoop-2.7.7/logs/yarn-hadoop-nodemanager-hufu03.out
hufu02: starting nodemanager, logging to /home/hadoop/hadoop-2.7.7/logs/yarn-hadoop-nodemanager-hufu02.out
hufu04: starting nodemanager, logging to /home/hadoop/hadoop-2.7.7/logs/yarn-hadoop-nodemanager-hufu04.out

10.验证是否启动成功

##hufu01
[hadoop@hufu01 hadoop]$ jps
9409 Jps
8117 ResourceManager
7560 SecondaryNameNode
7357 NameNode

##hufu02
[root@hufu02 ~]# jps
8160 NodeManager
10020 Jps
9926 DataNode

##hufu03
[root@hufu03 ~]# jps
7714 NodeManager
9222 DataNode
9304 Jps

##hufu04
[hadoop@hufu04 root]$ jps
8533 DataNode
7710 NodeManager
8623 Jps