centos下hadoop2.6.0集群搭建详细过程

一 、centos集群环境配置
1.创建一个namenode节点，5个datanode节点

主机名	IP
namenodezsw	192.168.129.158
datanode1zsw	192.168.129.159
datanode2zsw	192.168.129.160
datanode3zsw	192.168.129.161
datanode4zsw	192.168.129.162
datanode5zsw	192.168.129.163

2.关闭防火墙，设置selinux为disabled
#service iptables stop
#chkconfig iptables off

设置selinux为disabled,如下图所示
#vim /etc/selinux/config

重启后生效，建议全部配置完成后再全部重启。
3.配置hosts文件
将各节点对应的主机名与IP地址记录在hosts文件中
vi /etc/hosts

4.配置java环境
本文所用java安装包为jdk-7u25-linux-x64.tar.gz(百度上各种版本的都有)
解压到/opt目录下
修改环境变量：
#vi /etc/profile
在文件末尾添加以下内容
export JAVA_HOME=/opt/jdk1.7.0_25
export JAR_HOME=/opt/jdk1.7.0_25/jre
export ClASSPATH=$JAVA_HOME/lib/tools.jar:$JAVA_HOME/lib/dt.jar:$JAR_HOME/lib
export PATH=$JAVA_HOME/bin:$PATH
保存后退出，执行
#source etcprofile
查看java版本:
#java -version

显示上图结果说明配置成功
注意：使用source etcprofile命令尽在本终端有效，重启后才全部生效
提示：namenode节点和datanode节点上述配置都相同
二、设置各节点间SSH无密码通信
在一个节点namenodezsw上操作
1.生成密钥对
#ssh-keygen -t rsa
按三次回车，结果如下图

2.将各个节点生成的公有密钥添加到authorized_keys
#cat .ssh/id_rsa.pub > .ssh/authorized_keys

#ssh 192.168.129.159 ssh-keygen -t rsa
#ssh 192.168.129.159 cat ~/.ssh/id_rsa.pub >>.ssh/authorized_keys
#ssh 192.168.129.160 ssh-keygen -t rsa
#ssh 192.168.129.160 cat ~/.ssh/id_rsa.pub >>.ssh/authorized_keys
#ssh 192.168.129.161 ssh-keygen -t rsa
#ssh 192.168.129.161 cat ~/.ssh/id_rsa.pub >>.ssh/authorized_keys
#ssh 192.168.129.162 ssh-keygen -t rsa
#ssh 192.168.129.162 cat ~/.ssh/id_rsa.pub >>.ssh/authorized_keys
#ssh 192.168.129.163 ssh-keygen -t rsa
#ssh 192.168.129.163 cat ~/.ssh/id_rsa.pub >>.ssh/authorized_keys

3.将authorized_keys文件传到各个节点
#scp /root/.ssh/authorized_keys root@192.168.129.159:/root/.ssh/authorized_keys
#scp /root/.ssh/authorized_keys root@192.168.129.160:/root/.ssh/authorized_keys
#scp /root/.ssh/authorized_keys root@192.168.129.161:/root/.ssh/authorized_keys
#scp /root/.ssh/authorized_keys root@192.168.129.162:/root/.ssh/authorized_keys
#scp /root/.ssh/authorized_keys root@192.168.129.163:/root/.ssh/authorized_keys

4.测试
#ssh 192.168.129.159 date
#ssh datanode1zsw date
1个namenode节点，5个datanode节点以此类推
两次ssh命令：
第一遍都需要输入yes，然后显示时间
第二遍则直接显示时间，说明配置成功

说明：每个节点上都要ssh命令其他的节点主机名和IP一下，检测是否可以
三、hadoop集群搭建
1.去hadoop官网或者百度下载hadoop-2.6.0-tar.gz，然后解压到namenode的/opt目录下
2.修改配置文件
#cd /opt/hadoop-2.6.0/etc/hadoop

①修改 hadoop-env.sh和yarn-env.sh
export JAVA_HOME=/opt/jdk1.7.0_25
②修改core-site.xml

<configuration>

         <property>

               <name>hadoop.tmp.dir</name>

                <value>/opt/hadoop-2.6.0/tmp</value>

               <description>Abase for other temporarydirectories.</description>

       </property>

       <property>

               <name>fs.defaultFS</name>

               <value>hdfs://namenodezsw:9000</value>

        </property>

       <property>

               <name>io.file.buffer.size</name>

               <value>4096</value>

       </property>

</configuration>

③修改hdfs-site.xml文件

configuration>

   <property>

         <name>dfs.namenode.name.dir</name>

         <value>file:///opt/hadoop-2.6.0/dfs/name</value>

   </property>

       <property>

        <name>dfs.datanode.data.dir</name>

        <value>file:///opt/hadoop-2.6.0/dfs/data</value>

   </property>

   <property>

        <name>dfs.replication</name>

        <value>2</value>

   </property>

   <property>

       <name>dfs.nameservices</name>

       <value>h1</value>

   </property>

   <property>

       <name>dfs.namenode.secondary.http-address</name>

       <value>namenodezsw:50090</value>

   </property>

    <property>

       <name>dfs.webhdfs.enabled</name>

       <value>true</value>

   </property>

</configuration>

④修改mapred-site.xml
cp mapred-site.xml.template mapred-site.xml

<configuration>

   <property>

       <name>mapreduce.framework.name</name>

       <value>yarn</value>

       <final>true</final>

   </property>



   <property>

       <name>mapreduce.jobtracker.http.address</name>

       <value>namenodezsw:50030</value>

   </property>

   <property>

       <name>mapreduce.jobhistory.address</name>

       <value>namenodezsw:10020</value>

   </property>

   <property>

       <name>mapreduce.jobhistory.webapp.address</name>

       <value>namenodezsw:19888</value>

   </property>

   <property>

       <name>mapred.job.tracker</name>

        <value>http://namenodezsw:9001</value>

   </property>

</configuration>

⑤修改yarn-site.xml

<configuration> 

<!-- Site specific YARN configuration properties-->

   <property>

       <name>yarn.resourcemanager.hostname</name>

       <value>namenodezsw</value>

    </property>



   <property>

       <name>yarn.nodemanager.aux-services</name>

       <value>mapreduce_shuffle</value>

   </property>

   <property>

       <name>yarn.resourcemanager.address</name>

       <value>namenodezsw:8032</value>

   </property>

   <property>

       <name>yarn.resourcemanager.scheduler.address</name>

        <value>namenodezsw:8030</value>

   </property>

   <property>

       <name>yarn.resourcemanager.resource-tracker.address</name>

       <value>namenodezsw:8031</value>

   </property>

   <property>

       <name>yarn.resourcemanager.admin.address</name>

       <value>namenodezsw:8033</value>

   </property>

   <property>

       <name>yarn.resourcemanager.webapp.address</name>

       <value>namenodezsw:8088</value>

   </property>

</configuration>

⑥修改slaves文件

⑦配置环境变量
# vi /etc/profile
export JAVA_HOME=/opt/jdk1.7.0_25
export HADOOP_HOME=/opt/hadoop-2.6.0
export JAR_HOME=/opt/jdk1.7.0_25/jre
export CLASSPATH=$JAVA_HOME/lib/tools.jar:$JAVA_HOME/lib/dt.jar:$JAR_HOME/lib
export PATH=$JAVA_HOME/bin:$HADOOP_HOME/bin:$HADOOP_HOME/sbin:$PATH
环境变量配置同样source /etc/profile命令本终端有效，重启后都有效
至此，修改完成
3.启动hadoop
使用scp -r /opt/hadoop-2.6.0/  hostname:/opt/命令将hadoop文件依次拷贝到5个datanode节点上。
在namenode上操作：
首先格式化
#hadoop namenode -format
启动所有服务
#start-all.sh

4.验证
namenode上：
#jps

datanode上：
#jps

网页管理端:

也可以使用 hadoop dfsadmin -report命令查看总体情况
至此集群搭建全部完成