Ubuntu14.04下安装Hadoop2.６.0&nb…

创建hadoop用户 ：
sudo adduser -ingroup hadoop hadoop

为hadoop用户添加权限：
sudo gedit /etc/sudoers
　　root    ALL=(ALL:ALL) ALL下添加：
　　hadoop    ALL=(ALL:ALL) ALL

安装ssh：
sudo apt-get install ssh
sudo apt-get install rsync
或sudo apt-get install openssh-server
启动　sudo /etc/init.d/ssh start
设置免密码登录，生成私钥和公钥　ssh-keygen -t rsa -P ""
登录　ssh localhost　退出exit

查看JDK路径：
update-alternatives - -config java

hadoop安装配置
移至　sudo mv hadoop-2.６.0 /usr/local/hadoop
权限　sudo chmod 774 /usr/local/hadoop
配置.bashrc文件　sudo gedit ~/.bashrc　末尾添加
　　#HADOOP VARIABLES START
　　export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64
　　export HADOOP_INSTALL=/usr/local/hadoop
　　export PATH=$PATH:$HADOOP_INSTALL/bin
　　export PATH=$PATH:$HADOOP_INSTALL/sbin
　　export HADOOP_MAPRED_HOME=$HADOOP_INSTALL
　　export HADOOP_COMMON_HOME=$HADOOP_INSTALL
　　export HADOOP_HDFS_HOME=$HADOOP_INSTALL
　　export YARN_HOME=$HADOOP_INSTALL
　　export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_INSTALL/lib/native
　　export HADOOP_OPTS="-Djava.library.path=$HADOOP_INSTALL/lib"
　　#HADOOP VARIABLES END　　
配置生效　source ~/.bashrc
配置hadoop-env.sh文件　sudo gedit /usr/local/hadoop/etc/hadoop/hadoop-env.sh
　　修改　export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64

安装完成，测试：
/usr/local/hadoop下mkdir input

cp README.txt input

bin/hadoop jar share/hadoop/mapreduce/sources/hadoop-mapreduce-examples-2.4.0-sources.jar org.apache.hadoop.examples.WordCount input output

cat output/*　查看字符统计结果......