Hi This Could be due to the Following reason 1) The *NameNode <http://wiki.apache.org/hadoop/NameNode>* does not have any available DataNodes 2) Namenode not able to start properly 3) other wise some IP Issue . Note:- Pleaes mention localhost instead of 127.0.0.1 (If it is in local)
Follow URL: http://wiki.apache.org/hadoop/FAQ#What_does_.22file_could_only_be_replicated_to_0_nodes.2C_instead_of_1.22_mean.3F Thanks samir On Sat, May 19, 2012 at 8:59 PM, Todd McFarland <toddmcf2...@gmail.com>wrote: > Hi folks, > > (Resending to this group, sent to common-dev before, pretty sure that's for > Hadoop internal development - sorry for that..) > > I'm pretty stuck here. I've been researching for hours and I haven't made > any forward progress on this one. > > I have a vmWare installation of Cloudera Hadoop 0.20. The following > commands to create a directory and copy a file from the shared folder *work > fine*, so I'm confident everything is setup correctly: > > [cloudera@localhost bin]$ hadoop fs -mkdir /user/cloudera/testdir > [cloudera@localhost bin]$ hadoop fs -put /mnt/hgfs/shared_folder/file1.txt > /user/cloudera/testdir/file1.txt > > The file shows up fine in the HDFS doing it this way on the Linux VM. > > *However*, when I try doing the equivalent operation in Java everything > works great until I try to close() FSDataOutputStream. > I'm left with the new directory and a zero byte size file. One suspicious > thing is that the user is "admin" instead of "cloudera" which I haven't > figured out why. Here is the error: > > 12/05/19 09:45:46 INFO hdfs.DFSClient: Exception in createBlockOutputStream > 127.0.0.1:50010 java.net.ConnectException: Connection refused: no further > information > 12/05/19 09:45:46 INFO hdfs.DFSClient: Abandoning block > blk_1931357292676354131_1068 > 12/05/19 09:45:46 INFO hdfs.DFSClient: Excluding datanode 127.0.0.1:50010 > 12/05/19 09:45:46 WARN hdfs.DFSClient: DataStreamer Exception: > org.apache.hadoop.ipc.RemoteException: java.io.IOException: File > /user/admin/testdir/file1.txt could only be replicated to 0 nodes, instead > of 1 > at > > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:1533) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.addBlock(NameNode.java:667) > at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) > at > > sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) > at > > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) > > There are certainly lots of search references to "*could only be replicated > to 0 nodes, instead of 1*" but chasing down those suggestions hasn't > helped. > I have run *jps* and* netstat* and that looks good. All services are > running, all port seem to be good. The *health check* looks good, plenty > of disk space, no failed nodes... > > Here is the java (it fails when it hits "fs.close()": > > import java.io.BufferedReader; > import java.io.FileInputStream; > import java.io.FileReader; > import java.io.IOException; > import org.apache.hadoop.conf.Configuration; > import org.apache.hadoop.fs.FSDataInputStream; > import org.apache.hadoop.fs.FSDataOutputStream; > import org.apache.hadoop.fs.FileSystem; > import org.apache.hadoop.fs.Path; > > public class TestFileTrans { > > public static void main(String[] args) { > > Configuration config = new Configuration(); > > config.addResource(new > Path("c:/_bigdata/client_libs/core-site.xml")); > config.addResource(new > Path("c:/_bigdata/client_libs/hdfs-site.xml")); > > System.out.println("hadoop.tmp.dir: " + > config.get("hadoop.tmp.dir")); > try{ > FileSystem dfs = FileSystem.get(config); > > // this will default to admin unless the workingDirectory is > explicitly set.. > > System.out.println("HDFS Working Directory: " + > dfs.getWorkingDirectory().toString()); > > String dirName = "testdir"; > Path src = new Path(dfs.getWorkingDirectory()+"/"+dirName); > dfs.mkdirs(src); > > System.out.println("HDFS Directory created: " + > dfs.getWorkingDirectory().toString()); > > loadFile(dfs, src); > > }catch(IOException e){ > System.out.println("Error" + e.getMessage()); > } > > } > > private static void loadFile(FileSystem dfs, Path src) throws > IOException{ > > FileInputStream fis = new > FileInputStream("c:/_bigdata/shared_folder/file1.txt"); > > int len = fis.available(); > > byte[] btr = new byte[len]; > > fis.read(btr); > > FSDataOutputStream fs = dfs.create(new Path(src.toString() > +"/file1.txt")); > > fs.write(btr); > > fs.flush(); > fs.close(); > > } > } > > Any help would be greatly appreciated! >
