Jun 252012
 

A newbie note.

I got this while running a streaming job:

12/06/26 05:43:05 ERROR streaming.StreamJob: Error Launching job : java.io.IOException: java.lang.NullPointerException
at org.apache.hadoop.mapred.QueueManager.getQueueACL(QueueManager.java:382)
at org.apache.hadoop.mapred.JobTracker.getQueueAdmins(JobTracker.java:4444)
at sun.reflect.GeneratedMethodAccessor19.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:557)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1434)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1430)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1157)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:1428)

Turned out it’s an ACL problem. Running “hadoop queue -showacls” gives me the list of queues that I have access, then relaunch the task with:

hadoop jar $HADOOP_HOME/contrib/streaming/hadoop-streaming-0.20.2-cdh3u1.jar \
-Dmapred.job.queue.name=queue_i_have_access \
….

and everything runs smootly.

I will post more newbie comments here.