I downloaded the Cloudera VM on my Windows 7 laptop to play around. I am trying to connect to the Hadoop instance running in the VM from Windows. I did an ifconfig and got the IP address of the VM. I can connect to the web interfaces running in the VM from Firefox running on my Windows box so i know i can connect at least to that.
So next, i tried to connect to Hadoop from Java.
public class FileSystemWriter
{
static
{
URL.setURLStreamHandlerFactory( new FsUrlStreamHandlerFactory() );
}
public static void main( String[] args ) throws Exception
{
String uri = "hdfs://192.168.171.128/user";
Configuration conf = new Configuration();
System.out.println( "uri: " + uri );
FileSystem fs = FileSystem.get( URI.create( uri ), conf );
}
}
But i get errors.
uri: hdfs://192.168.171.128/user
Aug 9, 2011 8:29:26 AM org.apache.hadoop.ipc.Client$Connec开发者_Python百科tion
handleConnectionFailure
INFO: Retrying connect to server: /192.168.171.128:8020. Already tried
0 time(s).
Aug 9, 2011 8:29:28 AM org.apache.hadoop.ipc.Client$Connection
handleConnectionFailure
INFO: Retrying connect to server: /192.168.171.128:8020. Already tried
1 time(s).
Aug 9, 2011 8:29:30 AM org.apache.hadoop.ipc.Client$Connection
handleConnectionFailure
INFO: Retrying connect to server: /192.168.171.128:8020. Already tried
2 time(s).
Can anyone help me out?
First, try to connect over hftp .
uri = "hftp://172.16.xxx.xxx:50070/";
System.out.println( "uri: " + uri );
Configuration conf = new Configuration();
FileSystem fs = FileSystem.get( URI.create( uri ), conf );
fs.printStatistics();
If you see something (no exceptions), then you are connected.
If you do not, then your problem is not HDFS, but rather, your problem is that you have a bad ip, or hadoop isn't running, or your ports are blocked... etc...
Make sure your Namenode is listening on port 8020. You can check with this command:
hadoop fs -ls hdfs://namenode(ip):8020
If this check fails, type
vim HADOOP_HOME/conf/core-site.xml
and see your namenode port in this entry offs.default.name
.Change your java code:
String uri = "hdfs://192.168.171.128:portOfNameNode/user";
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