四、系统配置

1关闭防火墙

chkconfig iptables off(永久性关闭)

配置主机名和hosts文件

2、SSH无密码验证配置

因为Hadoop运行过程需要远程管理Hadoop的守护进程，NameNode节点需要通过SSH（Secure Shell）链接各个DataNode节点，停止或启动他们的进程，所以SSH必须是没有密码的，所以我们要把NameNode节点和DataNode节点配制成无秘密通信，同理DataNode也需要配置无密码链接NameNode节点。

在每一台机器上配置：

vi /etc/ssh/sshd_config打开

RSAAuthentication yes # 启用 RSA 认证，PubkeyAuthentication yes # 启用公钥私钥配对认证方式

Master01:运行：ssh-keygen –t rsa –P ‘‘  不输入密码直接enter

默认存放在 ／root／.ssh目录下,

cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys

[root@master01 .ssh]# ls

authorized_keys  id_rsa  id_rsa.pub  known_hosts

五、配置几个文件（各个节点一样）

 5.1.   hadoop/etc/hadoop/hadoop-env.sh 添加： 

# set to the root ofyour Java installation  
  export JAVA_HOME=/usr/java/latest  
   
  # Assuming your installation directory is/usr/local/hadoop  
  export HADOOP_PREFIX=/usr/local/hadoop  

5.2. etc/hadoop/core-site.xml

<configuration>  
    <property>  
         <name>fs.defaultFS</name>  
         <value>hdfs://c1:9000</value>  
    </property>
     <property>
     <name>hadoop.tmp.dir</name>
     <value>/usr/local/cdh/hadoop/data/tmp</value>
   </property>  
</configuration>

<configuration>   
 <property>   
    <!--开启web hdfs-->   
    <name>dfs.webhdfs.enabled</name>   
    <value>true</value>   
 </property>  
 <property>   
   <name>dfs.replication</name>   
   <value>2</value>   
 </property>  
 <property>   
    <name>dfs.namenode.name.dir</name>   
    <value>/usr/local/cdh/hadoop/data/dfs/name</value>   
    <description> namenode 存放name table(fsimage)本地目录（需要修改）</description>   
 </property>   
 <property>   
     <name>dfs.namenode.edits.dir</name>   
     <value>${dfs.namenode.name.dir}</value>   
     <description>namenode粗放 transactionfile(edits)本地目录（需要修改）</description>   
  </property>   
  <property>   
      <name>dfs.datanode.data.dir</name>   
      <value>/usr/local/cdh/hadoop/data/dfs/data</value>   
      <description>datanode存放block本地目录（需要修改）</description>   
  </property>
  <property>
     <name>dfs.permissions</name>
     <value>false</value>
   </property> 
<property>
     <name>dfs.permissions.enabled</name>
     <value>false</value>
</property>
</configuration>

<configuration>  
    <property>  
        <name>mapreduce.framework.name</name>  
        <value>yarn</value>  
    </property>  
</configuration>

# some Java parameters
export JAVA_HOME=/usr/local/java/jdk1.7.0_67

<configuration>
<property>
<name>yarn.resourcemanager.address</name>
<value>c1:8032</value>
</property>
<property>
<name>yarn.resourcemanager.scheduler.address</name>
<value>c1:8030</value>
</property>
<property>
<name>yarn.resourcemanager.resource-tracker.address</name>
<value>c1:8031</value>
</property>
<property>
<name>yarn.resourcemanager.admin.address</name>
<value>c1:8033</value>
</property>
<property>
<name>yarn.resourcemanager.webapp.address</name>
<value>c1:8088</value>
</property>
<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.ShuffleHandler</value>
</property> 
</configuration>

5.7. etc/hadoop/slaves

c2
c3

六：启动及验证安装是否成功

 格式化：要先格式化HDFS:

[html] view plaincopy
bin/hdfs namenode -format  
启动：

  sbin/start-dfs.sh

  sbin/start-yarn.sh

 [root@c1 hadoop]# jps
3250 Jps
2491 ResourceManager
2343 SecondaryNameNode
2170 NameNode

 datanode节点：

[root@c2 ~]# jps
4196 Jps
2061 DataNode
2153 NodeManager

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1.    
2.    
3.    
4. 1.   打开浏览器  
5.   NameNode - http://localhost:50070/  
6. 2.   创建文件夹  
7. 3.    $bin/hdfs dfs -mkdir /user  
8.   $ bin/hdfs dfs -mkdir /user/<username>  
9. 4.   Copy 文件  
10.   $ bin/hdfs dfs -put etc/hadoop input  
11. 5.   运行作业  
12.   $ bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-2.3.0-cdh5.1.0.jar grep input output ‘dfs[a-z.]+‘  
13. 6.   查看输出  
14.   $ bin/hdfs dfs -get output output  
15.   $ cat output/*