Hadoop学习心得，

Hadoop学习心得

修改root用户登录

sudo passwd root
sudo vi /etc/ssh/sshd_config
将PermitRootLogin这一项改为yes
sudo service ssh restart

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安装JDK JAVA环境配置

apt-get install openjdk-7-jdk

vim /etc/profile

export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64
export JRE_HOME=$JAVA_HOME/jre
export CLASSPATH=$JAVA_HOME/lib:$JRE_HOME/lib:$CLASSPATH
export PATH=$JAVA_HOME/bin:$JRE_HOME/bin:$PATH

source /etc/profile

安装Hadoop

wget http://mirror.bit.edu.cn/apache/hadoop/common/hadoop-1.2.1/hadoop-1.2.1.tar.gz

mv hadoop-1.2.1.tar.gz /opt/
cd /opt
tar -zxvf hadoop-1.2.1.tar.gz
cd hadoop-1.2.1/conf/
修改配置文件
1.vim hadoop-env.sh

export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64
2.vim core-site.xml


<property>
<name>hadoop.tmp.dir</name>
<value>/hadoop</value>
</property>
<property>
<name>dfs.name.dir</name>
<value>/hadoop/name</value>
</property>
<property>
<name>fs.default.name</name>
<value>hdfs://localhost:9000</value>
</property>

3.vim hdfs-site.xml

<property>
<name>dfs.data.dir</name>
<value>/hadoop/data</value>
</property>

4.vim mapred-site.xml
<property>
<name>dfs.data.dir</name>
<value>/hadoop/data</value>
</property>

5.vim /etc/profile
export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64
export JRE_HOME=$JAVA_HOME/jre
export HADOOP_HOME=/opt/hadoop-1.2.1
export CLASSPATH=$JAVA_HOME/lib:$JRE_HOME/lib:$CLASSPATH
export PATH=$JAVA_HOME/bin:$JRE_HOME/bin:$HADOOP_HOME/bin:$PATH

source /etc/profile

cd ..
cd bin/
hadoop namenode -format

cd /opt/hadoop-1.2.1/bin/

sudo apt-get install ssh
ssh-keygen -t dsa -P ” -f ~/.ssh/id_dsa
cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys
这时候输入 ssh -V 出现版本的话证明装成功了
ssh localhost
start-all.sh

输入JPS

则Hadoop运行正常

查看hadoop目录
root@VM-68-206-ubuntu:/opt/hadoop-1.2.1/bin# hadoop fs -ls /
Warning: $HADOOP_HOME is deprecated.
Found 1 items
drwxr-xr-x - root supergroup 0 2017-03-26 22:21 /hadoop
root@VM-68-206-ubuntu:/opt/hadoop-1.2.1/bin#