Hadoop on Ubuntu Talks

[noninoni]

Hi All,
I am new to Hadoop and I jus installed on Ubuntu 8.0.4 LTS as per guidance of a web site. I tested it and found working fine. I tried to copy a file but it is giving some error pls help me out

hadoop@excel-desktop:/usr/local/hadoop/hadoop-0.17.2.1$ bin/hadoop jar hadoop-0.17.2.1-examples.jar wordcount /home/hadoop/Download\ URLs.txt download-output
09/02/02 11:18:59 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 1 time(s).
09/02/02 11:19:00 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 2 time(s).
09/02/02 11:19:01 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 3 time(s).
09/02/02 11:19:02 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 4 time(s).
09/02/02 11:19:04 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 5 time(s).
09/02/02 11:19:05 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 6 time(s).
09/02/02 11:19:06 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 7 time(s).
09/02/02 11:19:07 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 8 time(s).
09/02/02 11:19:08 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 9 time(s).
09/02/02 11:19:09 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 10 time(s).
java.lang.RuntimeException: java.net.ConnectException: Connection refused
at org.apache.hadoop.mapred.JobConf.getWorkingDirecto ry(JobConf.java:356)
at org.apache.hadoop.mapred.FileInputFormat.setInputP aths(FileInputFormat.java:331)
at org.apache.hadoop.mapred.FileInputFormat.setInputP aths(FileInputFormat.java:304)
at org.apache.hadoop.examples.WordCount.run(WordCount .java:146)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.j ava:65)
at org.apache.hadoop.examples.WordCount.main(WordCoun t.java:155)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Nativ e Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Native MethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(De legatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at org.apache.hadoop.util.ProgramDriver$ProgramDescri ption.invoke(ProgramDriver.java:68)
at org.apache.hadoop.util.ProgramDriver.driver(Progra mDriver.java:139)
at org.apache.hadoop.examples.ExampleDriver.main(Exam pleDriver.java:53)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Nativ e Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Native MethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(De legatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at org.apache.hadoop.util.RunJar.main(RunJar.java:155 )
at org.apache.hadoop.mapred.JobShell.run(JobShell.jav a:194)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.j ava:65)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.j ava:79)
at org.apache.hadoop.mapred.JobShell.main(JobShell.ja va:220)
Caused by: java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketC hannelImpl.java:592)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.jav a:118)
at org.apache.hadoop.ipc.Client$Connection.setupIOstr eams(Client.java:174)
at org.apache.hadoop.ipc.Client.getConnection(Client. java:623)
at org.apache.hadoop.ipc.Client.call(Client.java:546)
at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java: 212)
at org.apache.hadoop.dfs.$Proxy0.getProtocolVersion(U nknown Source)
at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:313)
at org.apache.hadoop.dfs.DFSClient.createRPCNamenode( DFSClient.java:102)
at org.apache.hadoop.dfs.DFSClient.<init>(DFSClient.java:178)
at org.apache.hadoop.dfs.DistributedFileSystem.initia lize(DistributedFileSystem.java:68)
at org.apache.hadoop.fs.FileSystem.createFileSystem(F ileSystem.java:1280)
at org.apache.hadoop.fs.FileSystem.access$300(FileSys tem.java:56)
at org.apache.hadoop.fs.FileSystem$Cache.get(FileSyst em.java:1291)
at org.apache.hadoop.fs.FileSystem.get(FileSystem.jav a:203)
at org.apache.hadoop.fs.FileSystem.get(FileSystem.jav a:108)
at org.apache.hadoop.mapred.JobConf.getWorkingDirecto ry(JobConf.java:352)
... 21 more
:mad:

[myrtle1908]

I know nothing about Hadoop but this error:-


java.net.ConnectException: Connection refused

indicates that for whatever reason (firewall, invalid IP/hostname/port etc) the client was unable to connect to the host. Can you try something other than the loopback address 127.0.0.1, perhaps your hostname?

[noninoni]

Thanks for the reply. But i need specific to Hadoop on Ubuntu. Because the default net connection / URL is to be configured in some of the conf file. If any one has done this pls help me out. Thanks

[GatorGoodNews]

Perhaps you are getting this exception because you do not have password-less SSH set up, which is needed for Hadoop node communication.

If that does not solve the problem, then you may want to make sure that the namenode is in fact running at port 9000, and not on port 8020 or any other port

[pshirishreddy]

check out your /etc/hosts file

make sure your localhost is properly defined if not add an entry


127.0.0.1 localhost

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