Hadoop安装问题Ubuntu 10.10

Question

I have a Hadoop installation issue on Ubuntu 10.10. I successfully installed hadoop. I did "hadoop version" and it showed me version and other info. as it should have.

The issue happens when I open a new terminal window or I logout and re-login. I do "hadoop version" it says hadoop is not installed. Looks like I am missing something in settings.

I am using Ubuntu 10.10.

Any help is appreciated. Rajesh

Answer 1

Set HADOOP_HOME in the ~/.bashrc file instead of doing it through the terminal. When you set an environment variable through the shell it remains alive only till the time you are on the very same shell. And, once you are done with the setting (in the bashrc file) do not forget to source it. Alternatively you could logout and login again.

HTH

Answer 2

To access hadoop command outside HADOOP_HOME directory, you will have to add the path of hadoop binaries in system's PATH env variable.
You can do something like this (change the path as per your system) in your ~/.bashrc :

export JAVA_HOME=/usr/lib/jvm/java-7-oracle/
export HADOOP_HOME=/home/rootcss/ecosystem/hadoop
export PATH=$PATH:$HADOOP_HOME/bin

For details and explanation, you can check this . Please note that, it is for old version of hadoop.

Answer 3

For this You should set HADOOP_HOME in the ~/.bashrc file $nano ~/.bashrc

Add these lines at the end of the file replace hadoop path with your path.

export HADOOP_PREFIX="/home/username/hadoop-2.6.0-cdh5.5.1"
export PATH=$PATH:$HADOOP_PREFIX/bin
export PATH=$PATH:$HADOOP_PREFIX/sbin
export HADOOP_MAPRED_HOME=${HADOOP_PREFIX}
export HADOOP_COMMON_HOME=${HADOOP_PREFIX}
export HADOOP_HDFS_HOME=${HADOOP_PREFIX}
export YARN_HOME=${HADOOP_PREFIX}

Answer 4

I not sure which version of Hadoop you installed.

Open .bashrc file located in the /home/ <user_name> /.bashrc and enter the following lines at the end of the file as per your Hadoop version:

Hadoop-1.xx

export HADOOP_HOME=/usr/local/hadoop-1.2.1  //Enter path of Hadoop Folder
export PATH=$PATH:$HADOOP_HOME/bin

Hadoop-2.xx

export HADOOP_PREFIX="/usr/local/hadoop-2.6.0" //Enter path of Hadoop Folder
export PATH=$PATH:$HADOOP_PREFIX/bin
export PATH=$PATH:$HADOOP_PREFIX/sbin
export HADOOP_MAPRED_HOME=${HADOOP_PREFIX}
export HADOOP_COMMON_HOME=${HADOOP_PREFIX}

Execute .bashrc to update the system for the changes(necessary):

exec bash

Try the hadoop version command

hadoop version

If you need complete installation codes and steps, you can refer this page:

https://www.dezyre.com/hadoop-tutorial/big-data-hadoop-tutorial