Hi , I am using Hadoop 2.7 on Ubuntu 14.04 cluster. I have 1 NamedNode (IP - 192.168.56.101, HostName - ubuntu) and 2 DataNode (IP - 192.168.56.102, HostName - ubuntu2 and IP - 192.168.56.103, HostName - ubuntu3).
When I run : $HADOOP_HOME/bin/hadoop fs -put /home/file.txt /user/user1 It fails with the below error: ========================================= 15/10/04 15:18:11 WARN hdfs.DFSClient: DataStreamer Exception org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /user/hdfs1/1.txt._COPYING_ could only be replicated to 0 nodes instead of minReplication (=1). There are 0 datanode(s) running and no node(s) are excluded in this operation. at org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.chooseTarget4NewBlock(BlockManager.java:1550) ============================================ I see that in my DataNode logs , the DataNodes are trying to connect to itself, instead of the NamedNode. ============================================ 2015-10-04 13:42:14,498 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: ubuntu2/192.168.56.102:9000. Already tried 1 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1000 MILLISECONDS) ============================================== But, the entry in core-site.xml are identical for all 2 VMs. And the entry points to the NamedNode only (hdfs at port 9000) ============================================== *<configuration>* * <property>* * <name>fs.default.name <http://fs.default.name/></name>* * <value>hdfs://ubuntu:9000</value>* * </property>* *</configuration>* *==============================================* Thanks Binita