Hello !   I am performing extensive experiments over my 3-nodes (VMs) cluster. my VMs have a disk space of 50GB each, and checking the space available (on localhost:9870 (namenode's UI)) after 10 spark-submit application submissions reveal that the hard disks are almost plenty. How to delete that created data without restarting and reformatting the hdfs ?  I was thinking of a datanode clean up command to use here.   Thanks. ... View more

Hello,   I have configured & set Hadoop Cluster over 2 nodes and launch it along with Yarn like so :    On the master node : hdfs namenode -regular yarn resourcemanager   On the slave node :  hdfs datanode -regular yarn nodemanager And it shows through UI that there has been a connection established between the two machines that form the cluster. To note that start-dfs on the master node started both namenode and datanode even after setting slaves and hosts files. Now i submit an application (simple hello world) to Yarn : through this command : Spark-submit --class "main" --master yarn pathToJar   But i get the error  15/08/29 12:07:58 INFO Client: ApplicationManager is waiting for the ResourceManager  client token: N/A diagnostics: N/A ApplicationMaster host: N/A ApplicationMaster RPC port: -1 queue: root.hdfs start time: 1440864477580 final status: UNDEFINED  user: hdfs 15/08/29 12:07:59 INFO Client: Application report for application_1440861466017_0007 (state: ACCEPTED) 15/08/29 12:08:00 INFO Client: Application report for application_1440861466017_0007 (state: ACCEPTED) 15/08/29 12:08:01 INFO Client: Application report for application_1440861466017_0007 (state: ACCEPTED)...   What am i missing in my configuration ?     ... View more