Hadoop 2.2.0 fails running start-dfs.sh with Error: JAVA_HOME is not set and could not be found

Question

I have a work in progress installation of Hadoop in Ubuntu 12.x. I already had a `deploy` user which I plan to use to run hadoop in a cluster of machines. The following code demonstrate my problem basically I can `ssh olympus` no problems but `start-dfs.sh` fails doing exactly that: ``` deploy@olympus:~$ ssh olympus Welcome to Ubuntu 12.04.4 LTS (GNU/Linux 3.5.0-45-generic x86_64) * Documentation: https://help.ubuntu.com/ Last login: Mon Feb 3 18:22:27 2014 from olympus deploy@olympus:~$ echo $JAVA_HOME /opt/dev/java/1.7.0_51 deploy@olympus:~$ start-dfs.sh Starting namenodes on [olympus] olympus: Error: JAVA_HOME is not set and could not be found. ```

Accepted Answer

You can edit hadoop-env.sh file and set JAVA_HOME for Hadoop

Open the file and find the line as bellow

```
export JAVA_HOME=/usr/lib/j2sdk1.6-sun
```

Uncomment the line And update the java_home as per your environment

This will solve the problem with java_home.

Hadoop 2.2.0 fails running start-dfs.sh with Error: JAVA_HOME is not set and could not be found

Solution

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