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Posted to mapreduce-dev@hadoop.apache.org by Konstantin Boudnik <co...@apache.org> on 2013/05/01 07:45:37 UTC

Re: Versions - Confusion

I have put together this chart some time ago and am trying to keep it up to
date (more or less). The most latest update is available here:
  http://is.gd/axRlgJ
  
Sometimes picture worth a lot... you know ;)
  Cos

On Fri, Apr 26, 2013 at 11:09AM, Suresh S wrote:
> Hello,
> 
>         I was confused with Hadoop versioning.
> I found that,  some people working on version starting with "0".
> Some others, working on version starting with "2".
> Also, i was confused with "branch".
> 
> Which version is really current version.
> *Regards*
> *S.Suresh,*
> *Research Scholar,*
> *Department of Computer Applications,*
> *National Institute of Technology,*
> *Tiruchirappalli - 620015.*
> *+91-9941506562*

Re: Versions - Confusion

Posted by Harsh J <ha...@cloudera.com>.
Hi Naidu,

(a) As Steve already mentioned, please do not ask user questions on
any of the *-dev lists as the list is only for project development and
contributors, not general Q/A.
(b) I've moved your question to user@hadoop.apache.org which is a
proper list for general Q/A.
(c) It is not a good thing to hijack another ongoing thread with your
question. Please always send a new email with an appropriate subject
for every new question. You can read more about etiquettes at
http://www.catb.org/esr/faqs/smart-questions.html

Onto your answers:

(1) This is a possibly known jps bug. It shouldn't be of any concern
though, as its also related to what you're doing on your environment.
Read http://bugs.sun.com/view_bug.do?bug_id=6637230 and
http://bugs.sun.com/view_bug.do?bug_id=6602355.
(2) The 1.x versions were case-sensitive on asking Y or N. It will not
accept y the same as Y. This has been resolved in 2.x.

On Wed, May 1, 2013 at 12:22 PM, Naidu MS
<sa...@gmail.com> wrote:
> Hi i have two questions regarding hdfs and jps utility
>
> I am new to Hadoop and started leraning hadoop from the past week
>
> 1.when ever i start start-all.sh and jps in console it showing the
> processes started
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ jps*
> *22283 NameNode*
> *23516 TaskTracker*
> *26711 Jps*
> *22541 DataNode*
> *23255 JobTracker*
> *22813 SecondaryNameNode*
> *Could not synchronize with target*
>
> But along with the list of process stared it always showing *" Could not
> synchronize with target" *in the jps output. What is meant by "Could not
> synchronize with target"?  Can some one explain why this is happening?
>
>
> 2.Is it possible to format namenode multiple  times? When i enter the
>  namenode -format command, it not formatting the name node and showing the
> following ouput.
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ hadoop namenode -format*
> *Warning: $HADOOP_HOME is deprecated.*
> *
> *
> *13/05/01 12:08:04 INFO namenode.NameNode: STARTUP_MSG: *
> */*************************************************************
> *STARTUP_MSG: Starting NameNode*
> *STARTUP_MSG:   host = naidu/127.0.0.1*
> *STARTUP_MSG:   args = [-format]*
> *STARTUP_MSG:   version = 1.0.4*
> *STARTUP_MSG:   build =
> https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r
> 1393290; compiled by 'hortonfo' on Wed Oct  3 05:13:58 UTC 2012*
> *************************************************************/*
> *Re-format filesystem in /home/naidu/dfs/namenode ? (Y or N) y*
> *Format aborted in /home/naidu/dfs/namenode*
> *13/05/01 12:08:05 INFO namenode.NameNode: SHUTDOWN_MSG: *
> */*************************************************************
> *SHUTDOWN_MSG: Shutting down NameNode at naidu/127.0.0.1*
> *
> *
> *************************************************************/*
>
> Can someone help me in understanding this? Why is it not possible to format
> name node multiple times?
>
>
> Regards,
> Naidu
>
>
>
>
>
>
> On Wed, May 1, 2013 at 11:15 AM, Konstantin Boudnik <co...@apache.org> wrote:
>
>> I have put together this chart some time ago and am trying to keep it up to
>> date (more or less). The most latest update is available here:
>>   http://is.gd/axRlgJ
>>
>> Sometimes picture worth a lot... you know ;)
>>   Cos
>>
>> On Fri, Apr 26, 2013 at 11:09AM, Suresh S wrote:
>> > Hello,
>> >
>> >         I was confused with Hadoop versioning.
>> > I found that,  some people working on version starting with "0".
>> > Some others, working on version starting with "2".
>> > Also, i was confused with "branch".
>> >
>> > Which version is really current version.
>> > *Regards*
>> > *S.Suresh,*
>> > *Research Scholar,*
>> > *Department of Computer Applications,*
>> > *National Institute of Technology,*
>> > *Tiruchirappalli - 620015.*
>> > *+91-9941506562*
>>



-- 
Harsh J

Re: Versions - Confusion

Posted by Steve Loughran <st...@hortonworks.com>.
this is the kind of question you should take up with the user@hadoopmailing list

On 30 April 2013 23:52, Naidu MS <sa...@gmail.com> wrote:

> Hi i have two questions regarding hdfs and jps utility
>
> I am new to Hadoop and started leraning hadoop from the past week
>
> 1.when ever i start start-all.sh and jps in console it showing the
> processes started
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ jps*
> *22283 NameNode*
> *23516 TaskTracker*
> *26711 Jps*
> *22541 DataNode*
> *23255 JobTracker*
> *22813 SecondaryNameNode*
> *Could not synchronize with target*
>
> But along with the list of process stared it always showing *" Could not
> synchronize with target" *in the jps output. What is meant by "Could not
> synchronize with target"?  Can some one explain why this is happening?
>
>
> 2.Is it possible to format namenode multiple  times? When i enter the
>  namenode -format command, it not formatting the name node and showing the
> following ouput.
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ hadoop namenode -format*
> *Warning: $HADOOP_HOME is deprecated.*
> *
> *
> *13/05/01 12:08:04 INFO namenode.NameNode: STARTUP_MSG: *
> */*************************************************************
> *STARTUP_MSG: Starting NameNode*
> *STARTUP_MSG:   host = naidu/127.0.0.1*
> *STARTUP_MSG:   args = [-format]*
> *STARTUP_MSG:   version = 1.0.4*
> *STARTUP_MSG:   build =
> https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r
> 1393290; compiled by 'hortonfo' on Wed Oct  3 05:13:58 UTC 2012*
> *************************************************************/*
> *Re-format filesystem in /home/naidu/dfs/namenode ? (Y or N) y*
> *Format aborted in /home/naidu/dfs/namenode*
> *13/05/01 12:08:05 INFO namenode.NameNode: SHUTDOWN_MSG: *
> */*************************************************************
> *SHUTDOWN_MSG: Shutting down NameNode at naidu/127.0.0.1*
> *
> *
> *************************************************************/*
>
> Can someone help me in understanding this? Why is it not possible to format
> name node multiple times?
>
>
> Regards,
> Naidu
>
>
>
>
>
>
> On Wed, May 1, 2013 at 11:15 AM, Konstantin Boudnik <co...@apache.org>
> wrote:
>
> > I have put together this chart some time ago and am trying to keep it up
> to
> > date (more or less). The most latest update is available here:
> >   http://is.gd/axRlgJ
> >
> > Sometimes picture worth a lot... you know ;)
> >   Cos
> >
> > On Fri, Apr 26, 2013 at 11:09AM, Suresh S wrote:
> > > Hello,
> > >
> > >         I was confused with Hadoop versioning.
> > > I found that,  some people working on version starting with "0".
> > > Some others, working on version starting with "2".
> > > Also, i was confused with "branch".
> > >
> > > Which version is really current version.
> > > *Regards*
> > > *S.Suresh,*
> > > *Research Scholar,*
> > > *Department of Computer Applications,*
> > > *National Institute of Technology,*
> > > *Tiruchirappalli - 620015.*
> > > *+91-9941506562*
> >
>

Re: Versions - Confusion

Posted by Harsh J <ha...@cloudera.com>.
Hi Naidu,

(a) As Steve already mentioned, please do not ask user questions on
any of the *-dev lists as the list is only for project development and
contributors, not general Q/A.
(b) I've moved your question to user@hadoop.apache.org which is a
proper list for general Q/A.
(c) It is not a good thing to hijack another ongoing thread with your
question. Please always send a new email with an appropriate subject
for every new question. You can read more about etiquettes at
http://www.catb.org/esr/faqs/smart-questions.html

Onto your answers:

(1) This is a possibly known jps bug. It shouldn't be of any concern
though, as its also related to what you're doing on your environment.
Read http://bugs.sun.com/view_bug.do?bug_id=6637230 and
http://bugs.sun.com/view_bug.do?bug_id=6602355.
(2) The 1.x versions were case-sensitive on asking Y or N. It will not
accept y the same as Y. This has been resolved in 2.x.

On Wed, May 1, 2013 at 12:22 PM, Naidu MS
<sa...@gmail.com> wrote:
> Hi i have two questions regarding hdfs and jps utility
>
> I am new to Hadoop and started leraning hadoop from the past week
>
> 1.when ever i start start-all.sh and jps in console it showing the
> processes started
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ jps*
> *22283 NameNode*
> *23516 TaskTracker*
> *26711 Jps*
> *22541 DataNode*
> *23255 JobTracker*
> *22813 SecondaryNameNode*
> *Could not synchronize with target*
>
> But along with the list of process stared it always showing *" Could not
> synchronize with target" *in the jps output. What is meant by "Could not
> synchronize with target"?  Can some one explain why this is happening?
>
>
> 2.Is it possible to format namenode multiple  times? When i enter the
>  namenode -format command, it not formatting the name node and showing the
> following ouput.
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ hadoop namenode -format*
> *Warning: $HADOOP_HOME is deprecated.*
> *
> *
> *13/05/01 12:08:04 INFO namenode.NameNode: STARTUP_MSG: *
> */*************************************************************
> *STARTUP_MSG: Starting NameNode*
> *STARTUP_MSG:   host = naidu/127.0.0.1*
> *STARTUP_MSG:   args = [-format]*
> *STARTUP_MSG:   version = 1.0.4*
> *STARTUP_MSG:   build =
> https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r
> 1393290; compiled by 'hortonfo' on Wed Oct  3 05:13:58 UTC 2012*
> *************************************************************/*
> *Re-format filesystem in /home/naidu/dfs/namenode ? (Y or N) y*
> *Format aborted in /home/naidu/dfs/namenode*
> *13/05/01 12:08:05 INFO namenode.NameNode: SHUTDOWN_MSG: *
> */*************************************************************
> *SHUTDOWN_MSG: Shutting down NameNode at naidu/127.0.0.1*
> *
> *
> *************************************************************/*
>
> Can someone help me in understanding this? Why is it not possible to format
> name node multiple times?
>
>
> Regards,
> Naidu
>
>
>
>
>
>
> On Wed, May 1, 2013 at 11:15 AM, Konstantin Boudnik <co...@apache.org> wrote:
>
>> I have put together this chart some time ago and am trying to keep it up to
>> date (more or less). The most latest update is available here:
>>   http://is.gd/axRlgJ
>>
>> Sometimes picture worth a lot... you know ;)
>>   Cos
>>
>> On Fri, Apr 26, 2013 at 11:09AM, Suresh S wrote:
>> > Hello,
>> >
>> >         I was confused with Hadoop versioning.
>> > I found that,  some people working on version starting with "0".
>> > Some others, working on version starting with "2".
>> > Also, i was confused with "branch".
>> >
>> > Which version is really current version.
>> > *Regards*
>> > *S.Suresh,*
>> > *Research Scholar,*
>> > *Department of Computer Applications,*
>> > *National Institute of Technology,*
>> > *Tiruchirappalli - 620015.*
>> > *+91-9941506562*
>>



-- 
Harsh J

Re: Versions - Confusion

Posted by Harsh J <ha...@cloudera.com>.
Hi Naidu,

(a) As Steve already mentioned, please do not ask user questions on
any of the *-dev lists as the list is only for project development and
contributors, not general Q/A.
(b) I've moved your question to user@hadoop.apache.org which is a
proper list for general Q/A.
(c) It is not a good thing to hijack another ongoing thread with your
question. Please always send a new email with an appropriate subject
for every new question. You can read more about etiquettes at
http://www.catb.org/esr/faqs/smart-questions.html

Onto your answers:

(1) This is a possibly known jps bug. It shouldn't be of any concern
though, as its also related to what you're doing on your environment.
Read http://bugs.sun.com/view_bug.do?bug_id=6637230 and
http://bugs.sun.com/view_bug.do?bug_id=6602355.
(2) The 1.x versions were case-sensitive on asking Y or N. It will not
accept y the same as Y. This has been resolved in 2.x.

On Wed, May 1, 2013 at 12:22 PM, Naidu MS
<sa...@gmail.com> wrote:
> Hi i have two questions regarding hdfs and jps utility
>
> I am new to Hadoop and started leraning hadoop from the past week
>
> 1.when ever i start start-all.sh and jps in console it showing the
> processes started
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ jps*
> *22283 NameNode*
> *23516 TaskTracker*
> *26711 Jps*
> *22541 DataNode*
> *23255 JobTracker*
> *22813 SecondaryNameNode*
> *Could not synchronize with target*
>
> But along with the list of process stared it always showing *" Could not
> synchronize with target" *in the jps output. What is meant by "Could not
> synchronize with target"?  Can some one explain why this is happening?
>
>
> 2.Is it possible to format namenode multiple  times? When i enter the
>  namenode -format command, it not formatting the name node and showing the
> following ouput.
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ hadoop namenode -format*
> *Warning: $HADOOP_HOME is deprecated.*
> *
> *
> *13/05/01 12:08:04 INFO namenode.NameNode: STARTUP_MSG: *
> */*************************************************************
> *STARTUP_MSG: Starting NameNode*
> *STARTUP_MSG:   host = naidu/127.0.0.1*
> *STARTUP_MSG:   args = [-format]*
> *STARTUP_MSG:   version = 1.0.4*
> *STARTUP_MSG:   build =
> https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r
> 1393290; compiled by 'hortonfo' on Wed Oct  3 05:13:58 UTC 2012*
> *************************************************************/*
> *Re-format filesystem in /home/naidu/dfs/namenode ? (Y or N) y*
> *Format aborted in /home/naidu/dfs/namenode*
> *13/05/01 12:08:05 INFO namenode.NameNode: SHUTDOWN_MSG: *
> */*************************************************************
> *SHUTDOWN_MSG: Shutting down NameNode at naidu/127.0.0.1*
> *
> *
> *************************************************************/*
>
> Can someone help me in understanding this? Why is it not possible to format
> name node multiple times?
>
>
> Regards,
> Naidu
>
>
>
>
>
>
> On Wed, May 1, 2013 at 11:15 AM, Konstantin Boudnik <co...@apache.org> wrote:
>
>> I have put together this chart some time ago and am trying to keep it up to
>> date (more or less). The most latest update is available here:
>>   http://is.gd/axRlgJ
>>
>> Sometimes picture worth a lot... you know ;)
>>   Cos
>>
>> On Fri, Apr 26, 2013 at 11:09AM, Suresh S wrote:
>> > Hello,
>> >
>> >         I was confused with Hadoop versioning.
>> > I found that,  some people working on version starting with "0".
>> > Some others, working on version starting with "2".
>> > Also, i was confused with "branch".
>> >
>> > Which version is really current version.
>> > *Regards*
>> > *S.Suresh,*
>> > *Research Scholar,*
>> > *Department of Computer Applications,*
>> > *National Institute of Technology,*
>> > *Tiruchirappalli - 620015.*
>> > *+91-9941506562*
>>



-- 
Harsh J

Re: Versions - Confusion

Posted by Harsh J <ha...@cloudera.com>.
Hi Naidu,

(a) As Steve already mentioned, please do not ask user questions on
any of the *-dev lists as the list is only for project development and
contributors, not general Q/A.
(b) I've moved your question to user@hadoop.apache.org which is a
proper list for general Q/A.
(c) It is not a good thing to hijack another ongoing thread with your
question. Please always send a new email with an appropriate subject
for every new question. You can read more about etiquettes at
http://www.catb.org/esr/faqs/smart-questions.html

Onto your answers:

(1) This is a possibly known jps bug. It shouldn't be of any concern
though, as its also related to what you're doing on your environment.
Read http://bugs.sun.com/view_bug.do?bug_id=6637230 and
http://bugs.sun.com/view_bug.do?bug_id=6602355.
(2) The 1.x versions were case-sensitive on asking Y or N. It will not
accept y the same as Y. This has been resolved in 2.x.

On Wed, May 1, 2013 at 12:22 PM, Naidu MS
<sa...@gmail.com> wrote:
> Hi i have two questions regarding hdfs and jps utility
>
> I am new to Hadoop and started leraning hadoop from the past week
>
> 1.when ever i start start-all.sh and jps in console it showing the
> processes started
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ jps*
> *22283 NameNode*
> *23516 TaskTracker*
> *26711 Jps*
> *22541 DataNode*
> *23255 JobTracker*
> *22813 SecondaryNameNode*
> *Could not synchronize with target*
>
> But along with the list of process stared it always showing *" Could not
> synchronize with target" *in the jps output. What is meant by "Could not
> synchronize with target"?  Can some one explain why this is happening?
>
>
> 2.Is it possible to format namenode multiple  times? When i enter the
>  namenode -format command, it not formatting the name node and showing the
> following ouput.
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ hadoop namenode -format*
> *Warning: $HADOOP_HOME is deprecated.*
> *
> *
> *13/05/01 12:08:04 INFO namenode.NameNode: STARTUP_MSG: *
> */*************************************************************
> *STARTUP_MSG: Starting NameNode*
> *STARTUP_MSG:   host = naidu/127.0.0.1*
> *STARTUP_MSG:   args = [-format]*
> *STARTUP_MSG:   version = 1.0.4*
> *STARTUP_MSG:   build =
> https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r
> 1393290; compiled by 'hortonfo' on Wed Oct  3 05:13:58 UTC 2012*
> *************************************************************/*
> *Re-format filesystem in /home/naidu/dfs/namenode ? (Y or N) y*
> *Format aborted in /home/naidu/dfs/namenode*
> *13/05/01 12:08:05 INFO namenode.NameNode: SHUTDOWN_MSG: *
> */*************************************************************
> *SHUTDOWN_MSG: Shutting down NameNode at naidu/127.0.0.1*
> *
> *
> *************************************************************/*
>
> Can someone help me in understanding this? Why is it not possible to format
> name node multiple times?
>
>
> Regards,
> Naidu
>
>
>
>
>
>
> On Wed, May 1, 2013 at 11:15 AM, Konstantin Boudnik <co...@apache.org> wrote:
>
>> I have put together this chart some time ago and am trying to keep it up to
>> date (more or less). The most latest update is available here:
>>   http://is.gd/axRlgJ
>>
>> Sometimes picture worth a lot... you know ;)
>>   Cos
>>
>> On Fri, Apr 26, 2013 at 11:09AM, Suresh S wrote:
>> > Hello,
>> >
>> >         I was confused with Hadoop versioning.
>> > I found that,  some people working on version starting with "0".
>> > Some others, working on version starting with "2".
>> > Also, i was confused with "branch".
>> >
>> > Which version is really current version.
>> > *Regards*
>> > *S.Suresh,*
>> > *Research Scholar,*
>> > *Department of Computer Applications,*
>> > *National Institute of Technology,*
>> > *Tiruchirappalli - 620015.*
>> > *+91-9941506562*
>>



-- 
Harsh J

Re: Versions - Confusion

Posted by Harsh J <ha...@cloudera.com>.
Hi Naidu,

(a) As Steve already mentioned, please do not ask user questions on
any of the *-dev lists as the list is only for project development and
contributors, not general Q/A.
(b) I've moved your question to user@hadoop.apache.org which is a
proper list for general Q/A.
(c) It is not a good thing to hijack another ongoing thread with your
question. Please always send a new email with an appropriate subject
for every new question. You can read more about etiquettes at
http://www.catb.org/esr/faqs/smart-questions.html

Onto your answers:

(1) This is a possibly known jps bug. It shouldn't be of any concern
though, as its also related to what you're doing on your environment.
Read http://bugs.sun.com/view_bug.do?bug_id=6637230 and
http://bugs.sun.com/view_bug.do?bug_id=6602355.
(2) The 1.x versions were case-sensitive on asking Y or N. It will not
accept y the same as Y. This has been resolved in 2.x.

On Wed, May 1, 2013 at 12:22 PM, Naidu MS
<sa...@gmail.com> wrote:
> Hi i have two questions regarding hdfs and jps utility
>
> I am new to Hadoop and started leraning hadoop from the past week
>
> 1.when ever i start start-all.sh and jps in console it showing the
> processes started
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ jps*
> *22283 NameNode*
> *23516 TaskTracker*
> *26711 Jps*
> *22541 DataNode*
> *23255 JobTracker*
> *22813 SecondaryNameNode*
> *Could not synchronize with target*
>
> But along with the list of process stared it always showing *" Could not
> synchronize with target" *in the jps output. What is meant by "Could not
> synchronize with target"?  Can some one explain why this is happening?
>
>
> 2.Is it possible to format namenode multiple  times? When i enter the
>  namenode -format command, it not formatting the name node and showing the
> following ouput.
>
> *naidu@naidu:~/work/hadoop-1.0.4/bin$ hadoop namenode -format*
> *Warning: $HADOOP_HOME is deprecated.*
> *
> *
> *13/05/01 12:08:04 INFO namenode.NameNode: STARTUP_MSG: *
> */*************************************************************
> *STARTUP_MSG: Starting NameNode*
> *STARTUP_MSG:   host = naidu/127.0.0.1*
> *STARTUP_MSG:   args = [-format]*
> *STARTUP_MSG:   version = 1.0.4*
> *STARTUP_MSG:   build =
> https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r
> 1393290; compiled by 'hortonfo' on Wed Oct  3 05:13:58 UTC 2012*
> *************************************************************/*
> *Re-format filesystem in /home/naidu/dfs/namenode ? (Y or N) y*
> *Format aborted in /home/naidu/dfs/namenode*
> *13/05/01 12:08:05 INFO namenode.NameNode: SHUTDOWN_MSG: *
> */*************************************************************
> *SHUTDOWN_MSG: Shutting down NameNode at naidu/127.0.0.1*
> *
> *
> *************************************************************/*
>
> Can someone help me in understanding this? Why is it not possible to format
> name node multiple times?
>
>
> Regards,
> Naidu
>
>
>
>
>
>
> On Wed, May 1, 2013 at 11:15 AM, Konstantin Boudnik <co...@apache.org> wrote:
>
>> I have put together this chart some time ago and am trying to keep it up to
>> date (more or less). The most latest update is available here:
>>   http://is.gd/axRlgJ
>>
>> Sometimes picture worth a lot... you know ;)
>>   Cos
>>
>> On Fri, Apr 26, 2013 at 11:09AM, Suresh S wrote:
>> > Hello,
>> >
>> >         I was confused with Hadoop versioning.
>> > I found that,  some people working on version starting with "0".
>> > Some others, working on version starting with "2".
>> > Also, i was confused with "branch".
>> >
>> > Which version is really current version.
>> > *Regards*
>> > *S.Suresh,*
>> > *Research Scholar,*
>> > *Department of Computer Applications,*
>> > *National Institute of Technology,*
>> > *Tiruchirappalli - 620015.*
>> > *+91-9941506562*
>>



-- 
Harsh J

Re: Versions - Confusion

Posted by Naidu MS <sa...@gmail.com>.
Hi i have two questions regarding hdfs and jps utility

I am new to Hadoop and started leraning hadoop from the past week

1.when ever i start start-all.sh and jps in console it showing the
processes started

*naidu@naidu:~/work/hadoop-1.0.4/bin$ jps*
*22283 NameNode*
*23516 TaskTracker*
*26711 Jps*
*22541 DataNode*
*23255 JobTracker*
*22813 SecondaryNameNode*
*Could not synchronize with target*

But along with the list of process stared it always showing *" Could not
synchronize with target" *in the jps output. What is meant by "Could not
synchronize with target"?  Can some one explain why this is happening?


2.Is it possible to format namenode multiple  times? When i enter the
 namenode -format command, it not formatting the name node and showing the
following ouput.

*naidu@naidu:~/work/hadoop-1.0.4/bin$ hadoop namenode -format*
*Warning: $HADOOP_HOME is deprecated.*
*
*
*13/05/01 12:08:04 INFO namenode.NameNode: STARTUP_MSG: *
*/*************************************************************
*STARTUP_MSG: Starting NameNode*
*STARTUP_MSG:   host = naidu/127.0.0.1*
*STARTUP_MSG:   args = [-format]*
*STARTUP_MSG:   version = 1.0.4*
*STARTUP_MSG:   build =
https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r
1393290; compiled by 'hortonfo' on Wed Oct  3 05:13:58 UTC 2012*
*************************************************************/*
*Re-format filesystem in /home/naidu/dfs/namenode ? (Y or N) y*
*Format aborted in /home/naidu/dfs/namenode*
*13/05/01 12:08:05 INFO namenode.NameNode: SHUTDOWN_MSG: *
*/*************************************************************
*SHUTDOWN_MSG: Shutting down NameNode at naidu/127.0.0.1*
*
*
*************************************************************/*

Can someone help me in understanding this? Why is it not possible to format
name node multiple times?


Regards,
Naidu






On Wed, May 1, 2013 at 11:15 AM, Konstantin Boudnik <co...@apache.org> wrote:

> I have put together this chart some time ago and am trying to keep it up to
> date (more or less). The most latest update is available here:
>   http://is.gd/axRlgJ
>
> Sometimes picture worth a lot... you know ;)
>   Cos
>
> On Fri, Apr 26, 2013 at 11:09AM, Suresh S wrote:
> > Hello,
> >
> >         I was confused with Hadoop versioning.
> > I found that,  some people working on version starting with "0".
> > Some others, working on version starting with "2".
> > Also, i was confused with "branch".
> >
> > Which version is really current version.
> > *Regards*
> > *S.Suresh,*
> > *Research Scholar,*
> > *Department of Computer Applications,*
> > *National Institute of Technology,*
> > *Tiruchirappalli - 620015.*
> > *+91-9941506562*
>