安装前准备：
1、hostname、hosts修改
2、ssh无密码登陆
集群部署：
1、java环境安装
root@hadoop01:~# sudo apt-get install openjdk-7-jre openjdk-7-jdk -y
2、下载hadoop文件
root@hadoop01:~# wget http://apache.fayea.com/hadoop/common/hadoop-2.7.1/hadoop-2.7.1.tar.gz
root@hadoop01:~# tar -xvf hadoop-2.7.1.tar.gz -C /usr/local/
root@hadoop01:~# cd /usr/local/
root@hadoop01:/usr/local# mv hadoop-2.7.1/ hadoop
root@hadoop01:/usr/local# cd hadoop/etc/hadoop/
3、 修改hadoop配置文件
3.1 hadoop-env.sh
root@hadoop01:/usr/local/hadoop/etc/hadoop# vim hadoop-env.sh
修改如下几个环境变量：
export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64/
export HADOOP_HEAPSIZE=2000
3.2 masters(配置secondary namenode)
root@hadoop01:/usr/local/hadoop/etc/hadoop# vim masters
添加如下内容：
hadoop02
3.3 core-site.xml
root@hadoop01:/usr/local/hadoop/etc/hadoop# vim core-site.xml
修改后的内容如下：
<configuration>
<property>
<name>fs.defaultFS</name>
<value>hdfs://hadoop01:9000/</value>
</property>
<property>
<name>fs.default.name</name>
<value>hdfs://hadoop01:9000</value>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>file:/usr/local/hadoop/tmp</value>
<description>Abase for other temporary directories.</description>
</property>
<property>
<name>io.file.buffer.size</name>
<value>131702</value>
</property>
<property>
<name>fs.checkpoint.period</name>
<value>3600</value>
<description>The number of seconds between two periodic checkpoints.</description>
</property>
<property>
<name>fs.checkpoint.size</name>
<value>67108864</value>
</property>
