Frequent Errors during Installation or Startup of Oozie Server

In spite of the fact that, Oozie Installation Steps have been entered down quite intelligibly and makes one hallucinate it as a matter of a few minutes, but as per my experience, its not that easy.. So, to somehow make it easy for you, one of my previous post is a jest of all those docs that are meant to help you install Oozie. Still here in this post, I am providing the solution to the 5 most common errors that you might have unfortunately encountered.

Error 1 :

Cannot create /var/run/oozie/oozie.pid: Directory nonexistent

Solution : 

Changing the permissions of the run folder as in

sudo chmod -cR 777 ./run 

sudo chown root:root -R /var/run/

Error 2 :

put: org.apache.hadoop.security.AccessControlException: Permission denied: user=jt, access=WRITE, inode="user":root:supergroup:rwxr-xr-x

Solution :

Add the following entry to your hadoop setup's conf/hdfs-site.xml 

<property> 

<name>dfs.permissions</name> 

<value>false</value> 

</property> 

Error 3 :

put:org.apache.hadoop.hdfs.server.namenode.SafeModeException:Cannot create directory /user/jt/examples. Name node is in safe mode.

Solution :

Use "hadoop dfsadmin -safemode leave" command to make the namenode leave safe mode forcefully. 

Or use "hadoop dfsadmin -safemode wait" to block till NN leaves by itself. 

If you need to get your cluster up and running quickly, you can manipulate the parameter dfs.namenode.threshold.percent. 

If you set it to 0, NN will not enter safe mode. 

Error 4 :

E0902: Exception occured: [java.io.IOException: Call to localhost/127.0.0.1:9000 failed on local exception: java.io.EOFException]

Solution : 

Check whether the port nos of jobtracker and namenode are correctly set in the job.properties file of the application you are running. 

Error 5 :

Hadoop StartUp Issue :  Hadoop fs command not working and datanode is not running

Solution : 

localpath_to_hadoop_data_store/dfs/data/current/VERSION and localpath_to_hadoop_data_store/dfs/name/current/VERSION  should have the same ids , if they are not change that of the datanode(s) .

If these included one of the points where you were stuck up, I hope to have helped you. All the very best for Oozie ...