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From Diego Gutierrez <diego.gutier...@ucsp.edu.pe>
Subject Re: Request for a pointer to a MapReduce Program tutorial
Date Sat, 28 Dec 2013 20:14:12 GMT
Hi,

For the first question, the name of the file containing the response of MR
process is like that:  part-r-00000. This file is inside the output
directory.

The second question, to locate the file in your linux file system you have
to go to your datanode directory. This directory path is in your
hdfs-site.xml file in {HADOOP_INSTALLATION}/etc/hadoop. In my case the full
path of the MR response file is:
/home/user/hadoop/data2.2/hdfs/datanode/current/BP-1422783414-127.0.1.1-1387647958374/current/finalized.

where my datanode directory is: /home/user/hadoop/data2.2/hdfs/namenode.

In the /finalized directory, there are files named like that:
blk_1073741836. In one of those files is the MR response file. This aproach
is not good if you want to open the response with vi for example, instead
you can copy the response file into your linux file system using
*copyToLocal* command(
https://hadoop.apache.org/docs/current2/hadoop-project-dist/hadoop-common/FileSystemShell.html#copyToLocal).
The syntax could be like that: bin/hadoop dfs -copyToLocal
/output/part-r-00000 /home/user/

Hope this help


2013/12/28 Sitaraman Vilayannur <vrsitaramanietflists@gmail.com>

> Hi all,
>   Thanks much for the pointers. I ran word count it appears,
> successfully. Currently in inspected the output like so,
> /usr/local/Software/hadoop-2.2.0/bin/hadoop fs -cat
> /user/sitaraman/output/*
> Java HotSpot(TM) 64-Bit Server VM warning: You have loaded library
> /usr/local/Software/hadoop-2.2.0/lib/native/libhadoop.so.1.0.0 which
> might have disabled stack guard. The VM will try to fix the stack
> guard now.
> It's highly recommended that you fix the library with 'execstack -c
> <libfile>', or link it with '-z noexecstack'.
> 13/12/28 15:13:06 WARN util.NativeCodeLoader: Unable to load
> native-hadoop library for your platform... using builtin-java classes
> where applicable
> as      2
> do      1
> do:     1
> i       2
> not     1
> say     1
>
> What is the name of the file in the output directory?  Can i read it
> say using emacs or vi where will the directory /user/sitaraman/output
> be in the linux fs, that is how to locate where it is....
> Thanks again for all the help.
> Sitaraman
>
> On 12/28/13, Hardik Pandya <smarty.juice@gmail.com> wrote:
> > I recently blogged about it - hope it helps
> >
> >
> http://letsdobigdata.wordpress.com/2013/12/07/running-hadoop-mapreduce-application-from-eclipse-kepler/
> >
> > Regards,
> > Hardik
> >
> > On Fri, Dec 27, 2013 at 6:53 AM, Sitaraman Vilayannur <
> > vrsitaramanietflists@gmail.com> wrote:
> >
> >> Hi,
> >>  Would much appreciate a pointer to a mapreduce tutorial which explains
> >> how i can run a simulated cluster of mapreduce nodes on a single PC and
> >> write a Java program with the MapReduce Paradigm.
> >>  Thanks very much.
> >> Sitaraman
> >>
> >
>

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