Hi,

I am new to Hadoop., i install Hadoop as per
http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluster/<http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluste>
while running Word cont example i am getting *NullPointerException

*can some one please look in to this issue ?*

*Thanks in Advance*  !!!

*
duser@sujit:~/Desktop/hadoop$ bin/hadoop dfs -ls /user/hduser/data
Found 3 items
-rw-r--r--   1 hduser supergroup     674566 2012-03-06 23:04
/user/hduser/data/pg20417.txt
-rw-r--r--   1 hduser supergroup    1573150 2012-03-06 23:04
/user/hduser/data/pg4300.txt
-rw-r--r--   1 hduser supergroup    1423801 2012-03-06 23:04
/user/hduser/data/pg5000.txt

hduser@sujit:~/Desktop/hadoop$ bin/hadoop jar hadoop*examples*.jar
wordcount /user/hduser/data /user/hduser/gutenberg-outputd

12/03/06 23:14:33 INFO input.FileInputFormat: Total input paths to process
: 3
12/03/06 23:14:33 INFO mapred.JobClient: Running job: job_201203062221_0002
12/03/06 23:14:34 INFO mapred.JobClient:  map 0% reduce 0%
12/03/06 23:14:49 INFO mapred.JobClient:  map 66% reduce 0%
12/03/06 23:14:55 INFO mapred.JobClient:  map 100% reduce 0%
12/03/06 23:14:58 INFO mapred.JobClient: Task Id :
attempt_201203062221_0002_r_000000_0, Status : FAILED
Error: java.lang.NullPointerException
    at
java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)

12/03/06 23:15:07 INFO mapred.JobClient: Task Id :
attempt_201203062221_0002_r_000000_1, Status : FAILED
Error: java.lang.NullPointerException
    at
java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)

12/03/06 23:15:16 INFO mapred.JobClient: Task Id :
attempt_201203062221_0002_r_000000_2, Status : FAILED
Error: java.lang.NullPointerException
    at
java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)

12/03/06 23:15:31 INFO mapred.JobClient: Job complete: job_201203062221_0002
12/03/06 23:15:31 INFO mapred.JobClient: Counters: 20
12/03/06 23:15:31 INFO mapred.JobClient:   Job Counters
12/03/06 23:15:31 INFO mapred.JobClient:     Launched reduce tasks=4
12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=22084
12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all
reduces waiting after reserving slots (ms)=0
12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all maps
waiting after reserving slots (ms)=0
12/03/06 23:15:31 INFO mapred.JobClient:     Launched map tasks=3
12/03/06 23:15:31 INFO mapred.JobClient:     Data-local map tasks=3
12/03/06 23:15:31 INFO mapred.JobClient:     Failed reduce tasks=1
12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=16799
12/03/06 23:15:31 INFO mapred.JobClient:   FileSystemCounters
12/03/06 23:15:31 INFO mapred.JobClient:     FILE_BYTES_READ=740520
12/03/06 23:15:31 INFO mapred.JobClient:     HDFS_BYTES_READ=3671863
12/03/06 23:15:31 INFO mapred.JobClient:     FILE_BYTES_WRITTEN=2278287
12/03/06 23:15:31 INFO mapred.JobClient:   File Input Format Counters
12/03/06 23:15:31 INFO mapred.JobClient:     Bytes Read=3671517
12/03/06 23:15:31 INFO mapred.JobClient:   Map-Reduce Framework
12/03/06 23:15:31 INFO mapred.JobClient:     Map output materialized
bytes=1474341
12/03/06 23:15:31 INFO mapred.JobClient:     Combine output records=102322
12/03/06 23:15:31 INFO mapred.JobClient:     Map input records=77932
12/03/06 23:15:31 INFO mapred.JobClient:     Spilled Records=153640
12/03/06 23:15:31 INFO mapred.JobClient:     Map output bytes=6076095
12/03/06 23:15:31 INFO mapred.JobClient:     Combine input records=629172
12/03/06 23:15:31 INFO mapred.JobClient:     Map output records=629172
12/03/06 23:15:31 INFO mapred.JobClient:     SPLIT_RAW_BYTES=346
hduser@sujit:~/Desktop/hadoop$

Hi Sujit,

Please also tell us which version/distribution of Hadoop is this?

On Tue, Mar 6, 2012 at 11:27 PM, Sujit Dhamale <[EMAIL PROTECTED]> wrote:
> Hi,
>
> I am new to Hadoop., i install Hadoop as per
> http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluster/<http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluste>
>
>
> while running Word cont example i am getting *NullPointerException
>
> *can some one please look in to this issue ?*
>
> *Thanks in Advance*  !!!
>
> *
>
>
> duser@sujit:~/Desktop/hadoop$ bin/hadoop dfs -ls /user/hduser/data
> Found 3 items
> -rw-r--r--   1 hduser supergroup     674566 2012-03-06 23:04
> /user/hduser/data/pg20417.txt
> -rw-r--r--   1 hduser supergroup    1573150 2012-03-06 23:04
> /user/hduser/data/pg4300.txt
> -rw-r--r--   1 hduser supergroup    1423801 2012-03-06 23:04
> /user/hduser/data/pg5000.txt
>
> hduser@sujit:~/Desktop/hadoop$ bin/hadoop jar hadoop*examples*.jar
> wordcount /user/hduser/data /user/hduser/gutenberg-outputd
>
> 12/03/06 23:14:33 INFO input.FileInputFormat: Total input paths to process
> : 3
> 12/03/06 23:14:33 INFO mapred.JobClient: Running job: job_201203062221_0002
> 12/03/06 23:14:34 INFO mapred.JobClient:  map 0% reduce 0%
> 12/03/06 23:14:49 INFO mapred.JobClient:  map 66% reduce 0%
> 12/03/06 23:14:55 INFO mapred.JobClient:  map 100% reduce 0%
> 12/03/06 23:14:58 INFO mapred.JobClient: Task Id :
> attempt_201203062221_0002_r_000000_0, Status : FAILED
> Error: java.lang.NullPointerException
>    at
> java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
>    at
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
>    at
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
>
> 12/03/06 23:15:07 INFO mapred.JobClient: Task Id :
> attempt_201203062221_0002_r_000000_1, Status : FAILED
> Error: java.lang.NullPointerException
>    at
> java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
>    at
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
>    at
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
>
> 12/03/06 23:15:16 INFO mapred.JobClient: Task Id :
> attempt_201203062221_0002_r_000000_2, Status : FAILED
> Error: java.lang.NullPointerException
>    at
> java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
>    at
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
>    at
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
>
> 12/03/06 23:15:31 INFO mapred.JobClient: Job complete: job_201203062221_0002
> 12/03/06 23:15:31 INFO mapred.JobClient: Counters: 20
> 12/03/06 23:15:31 INFO mapred.JobClient:   Job Counters
> 12/03/06 23:15:31 INFO mapred.JobClient:     Launched reduce tasks=4
> 12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=22084
> 12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all
> reduces waiting after reserving slots (ms)=0
> 12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all maps
> waiting after reserving slots (ms)=0
> 12/03/06 23:15:31 INFO mapred.JobClient:     Launched map tasks=3
> 12/03/06 23:15:31 INFO mapred.JobClient:     Data-local map tasks=3
> 12/03/06 23:15:31 INFO mapred.JobClient:     Failed reduce tasks=1
> 12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=16799
> 12/03/06 23:15:31 INFO mapred.JobClient:   FileSystemCounters
> 12/03/06 23:15:31 INFO mapred.JobClient:     FILE_BYTES_READ=740520
> 12/03/06 23:15:31 INFO mapred.JobClient:     HDFS_BYTES_READ=3671863
> 12/03/06 23:15:31 INFO mapred.JobClient:     FILE_BYTES_WRITTEN=2278287
> 12/03/06 23:15:31 INFO mapred.JobClient:   File Input Format Counters
> 12/03/06 23:15:31 INFO mapred.JobClient:     Bytes Read=3671517

Harsh J

Hadoop version : hadoop-0.20.203.0rc1.tar
Operaring Syatem : ubuntu 11.10
On Wed, Mar 7, 2012 at 12:19 AM, Harsh J <[EMAIL PROTECTED]> wrote:

> Hi Sujit,
>
> Please also tell us which version/distribution of Hadoop is this?
>
> On Tue, Mar 6, 2012 at 11:27 PM, Sujit Dhamale <[EMAIL PROTECTED]>
> wrote:
> > Hi,
> >
> > I am new to Hadoop., i install Hadoop as per
> >
> http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluster/
> <
> http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluste
> >
> >
> >
> > while running Word cont example i am getting *NullPointerException
> >
> > *can some one please look in to this issue ?*
> >
> > *Thanks in Advance*  !!!
> >
> > *
> >
> >
> > duser@sujit:~/Desktop/hadoop$ bin/hadoop dfs -ls /user/hduser/data
> > Found 3 items
> > -rw-r--r--   1 hduser supergroup     674566 2012-03-06 23:04
> > /user/hduser/data/pg20417.txt
> > -rw-r--r--   1 hduser supergroup    1573150 2012-03-06 23:04
> > /user/hduser/data/pg4300.txt
> > -rw-r--r--   1 hduser supergroup    1423801 2012-03-06 23:04
> > /user/hduser/data/pg5000.txt
> >
> > hduser@sujit:~/Desktop/hadoop$ bin/hadoop jar hadoop*examples*.jar
> > wordcount /user/hduser/data /user/hduser/gutenberg-outputd
> >
> > 12/03/06 23:14:33 INFO input.FileInputFormat: Total input paths to
> process
> > : 3
> > 12/03/06 23:14:33 INFO mapred.JobClient: Running job:
> job_201203062221_0002
> > 12/03/06 23:14:34 INFO mapred.JobClient:  map 0% reduce 0%
> > 12/03/06 23:14:49 INFO mapred.JobClient:  map 66% reduce 0%
> > 12/03/06 23:14:55 INFO mapred.JobClient:  map 100% reduce 0%
> > 12/03/06 23:14:58 INFO mapred.JobClient: Task Id :
> > attempt_201203062221_0002_r_000000_0, Status : FAILED
> > Error: java.lang.NullPointerException
> >    at
> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
> >    at
> >
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
> >    at
> >
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
> >
> > 12/03/06 23:15:07 INFO mapred.JobClient: Task Id :
> > attempt_201203062221_0002_r_000000_1, Status : FAILED
> > Error: java.lang.NullPointerException
> >    at
> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
> >    at
> >
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
> >    at
> >
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
> >
> > 12/03/06 23:15:16 INFO mapred.JobClient: Task Id :
> > attempt_201203062221_0002_r_000000_2, Status : FAILED
> > Error: java.lang.NullPointerException
> >    at
> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
> >    at
> >
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
> >    at
> >
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
> >
> > 12/03/06 23:15:31 INFO mapred.JobClient: Job complete:
> job_201203062221_0002
> > 12/03/06 23:15:31 INFO mapred.JobClient: Counters: 20
> > 12/03/06 23:15:31 INFO mapred.JobClient:   Job Counters
> > 12/03/06 23:15:31 INFO mapred.JobClient:     Launched reduce tasks=4
> > 12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=22084
> > 12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all
> > reduces waiting after reserving slots (ms)=0
> > 12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all maps
> > waiting after reserving slots (ms)=0
> > 12/03/06 23:15:31 INFO mapred.JobClient:     Launched map tasks=3
> > 12/03/06 23:15:31 INFO mapred.JobClient:     Data-local map tasks=3
> > 12/03/06 23:15:31 INFO mapred.JobClient:     Failed reduce tasks=1
> > 12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=16799
> > 12/03/06 23:15:31 INFO mapred.JobClient:   FileSystemCounters

Hi,

I am new to Hadoop., i install Hadoop as per
http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluster/<http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluste>
while running Word cont example i am getting *NullPointerException

*can some one please look in to this issue ?*

*Thanks in Advance*  !!!

*Hadoop version : hadoop-0.20.203.0rc1.tar
Operaring Syatem : ubuntu 11.10

duser@sujit:~/Desktop/hadoop$ bin/hadoop dfs -ls /user/hduser/data
Found 3 items
-rw-r--r--   1 hduser supergroup     674566 2012-03-06 23:04
/user/hduser/data/pg20417.txt
-rw-r--r--   1 hduser supergroup    1573150 2012-03-06 23:04
/user/hduser/data/pg4300.txt
-rw-r--r--   1 hduser supergroup    1423801 2012-03-06 23:04
/user/hduser/data/pg5000.txt

hduser@sujit:~/Desktop/hadoop$ bin/hadoop jar hadoop*examples*.jar
wordcount /user/hduser/data /user/hduser/gutenberg-outputd

12/03/06 23:14:33 INFO input.FileInputFormat: Total input paths to process
: 3
12/03/06 23:14:33 INFO mapred.JobClient: Running job: job_201203062221_0002
12/03/06 23:14:34 INFO mapred.JobClient:  map 0% reduce 0%
12/03/06 23:14:49 INFO mapred.JobClient:  map 66% reduce 0%
12/03/06 23:14:55 INFO mapred.JobClient:  map 100% reduce 0%
12/03/06 23:14:58 INFO mapred.JobClient: Task Id :
attempt_201203062221_0002_r_
000000_0, Status : FAILED
Error: java.lang.NullPointerException
    at
java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)

12/03/06 23:15:07 INFO mapred.JobClient: Task Id :
attempt_201203062221_0002_r_000000_1, Status : FAILED
Error: java.lang.NullPointerException
    at
java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)

12/03/06 23:15:16 INFO mapred.JobClient: Task Id :
attempt_201203062221_0002_r_000000_2, Status : FAILED
Error: java.lang.NullPointerException
    at
java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
    at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)

12/03/06 23:15:31 INFO mapred.JobClient: Job complete: job_201203062221_0002
12/03/06 23:15:31 INFO mapred.JobClient: Counters: 20
12/03/06 23:15:31 INFO mapred.JobClient:   Job Counters
12/03/06 23:15:31 INFO mapred.JobClient:     Launched reduce tasks=4
12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=22084
12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all
reduces waiting after reserving slots (ms)=0
12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all maps
waiting after reserving slots (ms)=0
12/03/06 23:15:31 INFO mapred.JobClient:     Launched map tasks=3
12/03/06 23:15:31 INFO mapred.JobClient:     Data-local map tasks=3
12/03/06 23:15:31 INFO mapred.JobClient:     Failed reduce tasks=1
12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=16799
12/03/06 23:15:31 INFO mapred.JobClient:   FileSystemCounters
12/03/06 23:15:31 INFO mapred.JobClient:     FILE_BYTES_READ=740520
12/03/06 23:15:31 INFO mapred.JobClient:     HDFS_BYTES_READ=3671863
12/03/06 23:15:31 INFO mapred.JobClient:     FILE_BYTES_WRITTEN=2278287
12/03/06 23:15:31 INFO mapred.JobClient:   File Input Format Counters
12/03/06 23:15:31 INFO mapred.JobClient:     Bytes Read=3671517
12/03/06 23:15:31 INFO mapred.JobClient:   Map-Reduce Framework
12/03/06 23:15:31 INFO mapred.JobClient:     Map output materialized
bytes=1474341
12/03/06 23:15:31 INFO mapred.JobClient:     Combine output records=102322
12/03/06 23:15:31 INFO mapred.JobClient:     Map input records=77932
12/03/06 23:15:31 INFO mapred.JobClient:     Spilled Records=153640
12/03/06 23:15:31 INFO mapred.JobClient:     Map output bytes=6076095
12/03/06 23:15:31 INFO mapred.JobClient:     Combine input records=629172
12/03/06 23:15:31 INFO mapred.JobClient:     Map output records=629172
12/03/06 23:15:31 INFO mapred.JobClient:     SPLIT_RAW_BYTES=346
hduser@sujit:~/Desktop/hadoop$

Can some one please look in to below issue ??
Thanks in Advance

On Wed, Mar 7, 2012 at 9:09 AM, Sujit Dhamale <[EMAIL PROTECTED]>wrote:

> Hadoop version : hadoop-0.20.203.0rc1.tar
> Operaring Syatem : ubuntu 11.10
>
>
>
> On Wed, Mar 7, 2012 at 12:19 AM, Harsh J <[EMAIL PROTECTED]> wrote:
>
>> Hi Sujit,
>>
>> Please also tell us which version/distribution of Hadoop is this?
>>
>> On Tue, Mar 6, 2012 at 11:27 PM, Sujit Dhamale <[EMAIL PROTECTED]>
>> wrote:
>> > Hi,
>> >
>> > I am new to Hadoop., i install Hadoop as per
>> >
>> http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluster/
>> <
>> http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluste
>> >
>> >
>> >
>> > while running Word cont example i am getting *NullPointerException
>> >
>> > *can some one please look in to this issue ?*
>> >
>> > *Thanks in Advance*  !!!
>> >
>> > *
>> >
>> >
>> > duser@sujit:~/Desktop/hadoop$ bin/hadoop dfs -ls /user/hduser/data
>> > Found 3 items
>> > -rw-r--r--   1 hduser supergroup     674566 2012-03-06 23:04
>> > /user/hduser/data/pg20417.txt
>> > -rw-r--r--   1 hduser supergroup    1573150 2012-03-06 23:04
>> > /user/hduser/data/pg4300.txt
>> > -rw-r--r--   1 hduser supergroup    1423801 2012-03-06 23:04
>> > /user/hduser/data/pg5000.txt
>> >
>> > hduser@sujit:~/Desktop/hadoop$ bin/hadoop jar hadoop*examples*.jar
>> > wordcount /user/hduser/data /user/hduser/gutenberg-outputd
>> >
>> > 12/03/06 23:14:33 INFO input.FileInputFormat: Total input paths to
>> process
>> > : 3
>> > 12/03/06 23:14:33 INFO mapred.JobClient: Running job:
>> job_201203062221_0002
>> > 12/03/06 23:14:34 INFO mapred.JobClient:  map 0% reduce 0%
>> > 12/03/06 23:14:49 INFO mapred.JobClient:  map 66% reduce 0%
>> > 12/03/06 23:14:55 INFO mapred.JobClient:  map 100% reduce 0%
>> > 12/03/06 23:14:58 INFO mapred.JobClient: Task Id :
>> > attempt_201203062221_0002_r_000000_0, Status : FAILED
>> > Error: java.lang.NullPointerException
>> >    at
>> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
>> >    at
>> >
>> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
>> >    at
>> >
>> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
>> >
>> > 12/03/06 23:15:07 INFO mapred.JobClient: Task Id :
>> > attempt_201203062221_0002_r_000000_1, Status : FAILED
>> > Error: java.lang.NullPointerException
>> >    at
>> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
>> >    at
>> >
>> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
>> >    at
>> >
>> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
>> >
>> > 12/03/06 23:15:16 INFO mapred.JobClient: Task Id :
>> > attempt_201203062221_0002_r_000000_2, Status : FAILED
>> > Error: java.lang.NullPointerException
>> >    at
>> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
>> >    at
>> >
>> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
>> >    at
>> >
>> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
>> >
>> > 12/03/06 23:15:31 INFO mapred.JobClient: Job complete:
>> job_201203062221_0002
>> > 12/03/06 23:15:31 INFO mapred.JobClient: Counters: 20
>> > 12/03/06 23:15:31 INFO mapred.JobClient:   Job Counters
>> > 12/03/06 23:15:31 INFO mapred.JobClient:     Launched reduce tasks=4
>> > 12/03/06 23:15:31 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=22084
>> > 12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all
>> > reduces waiting after reserving slots (ms)=0
>> > 12/03/06 23:15:31 INFO mapred.JobClient:     Total time spent by all
>> maps
>> > waiting after reserving slots (ms)=0
>> > 12/03/06 23:15:31 INFO mapred.JobClient:     Launched map tasks=3

Hi Sujit,

I think it is a problem with the host names configuration.
Could you please check whether you added the host names of the master and
the slaves in the etc/hosts file of all the nodes.
On Mon, Apr 2, 2012 at 8:00 PM, Sujit Dhamale <[EMAIL PROTECTED]>wrote:

> Can some one please look in to below issue ??
> Thanks in Advance
>
> On Wed, Mar 7, 2012 at 9:09 AM, Sujit Dhamale <[EMAIL PROTECTED]
> >wrote:
>
> > Hadoop version : hadoop-0.20.203.0rc1.tar
> > Operaring Syatem : ubuntu 11.10
> >
> >
> >
> > On Wed, Mar 7, 2012 at 12:19 AM, Harsh J <[EMAIL PROTECTED]> wrote:
> >
> >> Hi Sujit,
> >>
> >> Please also tell us which version/distribution of Hadoop is this?
> >>
> >> On Tue, Mar 6, 2012 at 11:27 PM, Sujit Dhamale <
> [EMAIL PROTECTED]>
> >> wrote:
> >> > Hi,
> >> >
> >> > I am new to Hadoop., i install Hadoop as per
> >> >
> >>
> http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluster/
> >> <
> >>
> http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluste
> >> >
> >> >
> >> >
> >> > while running Word cont example i am getting *NullPointerException
> >> >
> >> > *can some one please look in to this issue ?*
> >> >
> >> > *Thanks in Advance*  !!!
> >> >
> >> > *
> >> >
> >> >
> >> > duser@sujit:~/Desktop/hadoop$ bin/hadoop dfs -ls /user/hduser/data
> >> > Found 3 items
> >> > -rw-r--r--   1 hduser supergroup     674566 2012-03-06 23:04
> >> > /user/hduser/data/pg20417.txt
> >> > -rw-r--r--   1 hduser supergroup    1573150 2012-03-06 23:04
> >> > /user/hduser/data/pg4300.txt
> >> > -rw-r--r--   1 hduser supergroup    1423801 2012-03-06 23:04
> >> > /user/hduser/data/pg5000.txt
> >> >
> >> > hduser@sujit:~/Desktop/hadoop$ bin/hadoop jar hadoop*examples*.jar
> >> > wordcount /user/hduser/data /user/hduser/gutenberg-outputd
> >> >
> >> > 12/03/06 23:14:33 INFO input.FileInputFormat: Total input paths to
> >> process
> >> > : 3
> >> > 12/03/06 23:14:33 INFO mapred.JobClient: Running job:
> >> job_201203062221_0002
> >> > 12/03/06 23:14:34 INFO mapred.JobClient:  map 0% reduce 0%
> >> > 12/03/06 23:14:49 INFO mapred.JobClient:  map 66% reduce 0%
> >> > 12/03/06 23:14:55 INFO mapred.JobClient:  map 100% reduce 0%
> >> > 12/03/06 23:14:58 INFO mapred.JobClient: Task Id :
> >> > attempt_201203062221_0002_r_000000_0, Status : FAILED
> >> > Error: java.lang.NullPointerException
> >> >    at
> >> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
> >> >    at
> >> >
> >>
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
> >> >    at
> >> >
> >>
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
> >> >
> >> > 12/03/06 23:15:07 INFO mapred.JobClient: Task Id :
> >> > attempt_201203062221_0002_r_000000_1, Status : FAILED
> >> > Error: java.lang.NullPointerException
> >> >    at
> >> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
> >> >    at
> >> >
> >>
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
> >> >    at
> >> >
> >>
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
> >> >
> >> > 12/03/06 23:15:16 INFO mapred.JobClient: Task Id :
> >> > attempt_201203062221_0002_r_000000_2, Status : FAILED
> >> > Error: java.lang.NullPointerException
> >> >    at
> >> > java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
> >> >    at
> >> >
> >>
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2900)
> >> >    at
> >> >
> >>
> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2820)
> >> >
> >> > 12/03/06 23:15:31 INFO mapred.JobClient: Job complete:
> >> job_201203062221_0002
> >> > 12/03/06 23:15:31 INFO mapred.JobClient: Counters: 20
> >> > 12/03/06 23:15:31 INFO mapred.JobClient:   Job Counters