@Thomas Larsson From the above list output on mount point , it seems that whole volume is not inaccessible , some of its subdir are inaccessible . what is the output of this command : sudo ls -la /mnt/data21/ ... View more

Adding to above , In this scenario datanode service may fail with "Incompatible ID" . To resolve you need to re-register the datanode as datanode will have the old namespaceid. ... View more

@sivasaravanakumar k If you are using any IDE to develop program like Eclipse then you can Add all required JAR file to program path and then build JAR using Eclipse. (http://tutoringcenter.cs.usfca.edu/resources/adding-user-libraries-in-eclipse.html) If you want to run your program on remote job where these jar might not be on classpath then build FAT/Executable jar using Eclipse. FAT JAR will ensure that all the required dependency is packaged with the program. (http://stackoverflow.com/questions/502960/eclipse-how-to-build-an-executable-jar-with-external-jar) You can also use build-tool like Maven to handle dependency for you. ... View more

@John Garrigan You can filter out the non-relevant terms in Mapper phase. Doing this will also increase your program performance as you are dropping unwanted data at early stage. You can use Regex to identify all words start with hashtag. Regex : ^# Psuedocode in above comment looks good .To do more optimization , you can introduce combiner class which will reduce network traffic between mapper and reducer phase. Combiner example code : https://hadoop.apache.org/docs/current/hadoop-mapreduce-client/hadoop-mapreduce-client-core/MapReduceTutorial.html Combiner concept : http://www.tutorialspoint.com/map_reduce/map_reduce_combiners.htm Hope this helps you ... View more

We are trying to abort one request from ambari-server with this command but it is not working it seems. Getting following exception in ambari-server: 11:28:25,579 WARN [Thread-20] ActionScheduler:189 - Exception received javax.persistence.RollbackException: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.4.0.v20120608-r11652): org.eclipse.persistence.exceptions.DatabaseException Internal Exception: java.sql.BatchUpdateException: Batch entry 0 UPDATE request SET end_time = 1463135305576 WHERE (request_id = 433) was aborted. Call getNextException to see the cause. Error Code: 0 Call: UPDATE request SET end_time = ? WHERE (request_id = ?) bind => [2 parameters bound] at org.eclipse.persistence.internal.jpa.transaction.EntityTransactionImpl.commitInternal(EntityTransactionImpl.java:102) at org.eclipse.persistence.internal.jpa.transaction.EntityTransactionImpl.commit(EntityTransactionImpl.java:63) at org.apache.ambari.server.orm.AmbariJpaLocalTxnInterceptor.invoke(AmbariJpaLocalTxnInterceptor.java:91) at org.apache.ambari.server.actionmanager.ActionDBAccessorImpl.endRequest(ActionDBAccessorImpl.java:302) at org.apache.ambari.server.actionmanager.ActionDBAccessorImpl.abortOperation(ActionDBAccessorImpl.java:150) at org.apache.ambari.server.actionmanager.ActionScheduler.abortOperationsForStage(ActionScheduler.java:636) at org.apache.ambari.server.actionmanager.ActionScheduler.processCancelledRequestsList(ActionScheduler.java:829) at org.apache.ambari.server.actionmanager.ActionScheduler.doWork(ActionScheduler.java:203) at org.apache.ambari.server.actionmanager.ActionScheduler.run(ActionScheduler.java:184) at java.lang.Thread.run(Thread.java:745) Caused by: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.4.0.v20120608-r11652): org.eclipse.persistence.exceptions.DatabaseException Internal Exception: java.sql.BatchUpdateException: Batch entry 0 UPDATE request SET end_time = 1463135305576 WHERE (request_id = 433) was aborted. Call getNextException to see the cause. Error Code: 0 ... View more

It seems that ambari-server has lost connection with ambari-agent somehow. Try these steps : 1. Stop ambari-server 2. Stop ambari-agent service on all nodes 3. Start ambari-agent service on all nodes 4. Start ambari-server server View logs of ambari-server and ambari-agent and see if it throws any error other than component in UNKOWN State. ... View more

can you also paste ambari-server log? ... View more

can you retry after clearing browser cache? ... View more