Seems like you havn't format your cluster (if its 1st time made).

On Fri, Nov 16, 2012 at 9:58 AM, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:

> Hi,
>
> Please help!
>
> I have installed a Hadoop Cluster with a single master (master1) and have
> HBase running on the HDFS.  Now I am setting up the second master
>  (master2) in order to form HA.  When I used JPS to check the cluster, I
> found :
>
> 2782 Jps
> 2126 NameNode
> 2720 SecondaryNameNode
> i.e. The datanode on this server could not be started
>
> In the log file, found:
> 2012-11-16 10:28:44,851 ERROR
> org.apache.hadoop.hdfs.server.datanode.DataNode: java.io.IOException:
> Incompatible namespaceIDs in /app/hadoop/tmp/dfs/data: namenode namespaceID
> = 1356148070; datanode namespaceID = 1151604993
>
>
>
> One of the possible solutions to fix this issue is to:  stop the cluster,
> reformat the NameNode, restart the cluster.
> QUESTION: As I already have HBASE running on the cluster, if I reformat
> the NameNode, do I need to reinstall the entire HBASE? I don't mind to have
> all data lost as I don't have many data in HBASE and HDFS, however I don't
> want to re-install HBASE again.
>
>
> On the other hand, I have tried another solution: stop the DataNode, edit
> the namespaceID in current/VERSION (i.e. set namespaceID=1151604993),
> restart the datanode, it doesn't work:
> Warning: $HADOOP_HOME is deprecated.
> starting master2, logging to
> /usr/local/hadoop-1.0.4/libexec/../logs/hadoop-hduser-master2-master2.out
> Exception in thread "main" java.lang.NoClassDefFoundError: master2
> Caused by: java.lang.ClassNotFoundException: master2
> at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
> at java.security.AccessController.doPrivileged(Native Method)
> at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
> at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
> at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
> at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
> Could not find the main class: master2.  Program will exit.
> QUESTION: Any other solutions?
>
>
>
> Thanks
>
>
>
>
>
>
>

Delete the VERSION for the datanode before format.

∞
Shashwat Shriparv
On Fri, Nov 16, 2012 at 1:15 PM, hadoop hive <[EMAIL PROTECTED]> wrote:

> Seems like you havn't format your cluster (if its 1st time made).
>
> On Fri, Nov 16, 2012 at 9:58 AM, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
>
>> Hi,
>>
>> Please help!
>>
>> I have installed a Hadoop Cluster with a single master (master1) and have
>> HBase running on the HDFS.  Now I am setting up the second master
>>  (master2) in order to form HA.  When I used JPS to check the cluster, I
>> found :
>>
>> 2782 Jps
>> 2126 NameNode
>> 2720 SecondaryNameNode
>> i.e. The datanode on this server could not be started
>>
>> In the log file, found:
>> 2012-11-16 10:28:44,851 ERROR
>> org.apache.hadoop.hdfs.server.datanode.DataNode: java.io.IOException:
>> Incompatible namespaceIDs in /app/hadoop/tmp/dfs/data: namenode namespaceID
>> = 1356148070; datanode namespaceID = 1151604993
>>
>>
>>
>> One of the possible solutions to fix this issue is to:  stop the cluster,
>> reformat the NameNode, restart the cluster.
>> QUESTION: As I already have HBASE running on the cluster, if I reformat
>> the NameNode, do I need to reinstall the entire HBASE? I don't mind to have
>> all data lost as I don't have many data in HBASE and HDFS, however I don't
>> want to re-install HBASE again.
>>
>>
>> On the other hand, I have tried another solution: stop the DataNode, edit
>> the namespaceID in current/VERSION (i.e. set namespaceID=1151604993),
>> restart the datanode, it doesn't work:
>> Warning: $HADOOP_HOME is deprecated.
>> starting master2, logging to
>> /usr/local/hadoop-1.0.4/libexec/../logs/hadoop-hduser-master2-master2.out
>> Exception in thread "main" java.lang.NoClassDefFoundError: master2
>> Caused by: java.lang.ClassNotFoundException: master2
>> at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
>> at java.security.AccessController.doPrivileged(Native Method)
>>  at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
>> at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
>>  at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
>> at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>> Could not find the main class: master2.  Program will exit.
>> QUESTION: Any other solutions?
>>
>>
>>
>> Thanks
>>
>>
>>
>>
>>
>>
>>
>

It seems u have formatted the namenode twice. In this case the namespace id
is not replicated to the datanodes.

Stop all the hadoop daemons and then try the following :

1. vi $PATH_TO_HADOOP_DATASTORE/dfs/name/current/VERSION and copy the
namespaceID value.
2.Now open a terminal on every machine having a datanode and do the
following:
vi $PATH_TO_HADOOP_DATASTORE/dfs/data/current/VERSION
Delete the entry corresponding to namespaceID and paste the value copied in
Step 1.
Save and exit.

Restart the hadoop daemons without formatting the namenode.

∞
Shashwat Shriparv
On Fri, Nov 16, 2012 at 1:22 PM, shashwat shriparv <
[EMAIL PROTECTED]> wrote:

> Delete the VERSION for the datanode before format.
>
>
>
> ∞
> Shashwat Shriparv
>
>
>
>
> On Fri, Nov 16, 2012 at 1:15 PM, hadoop hive <[EMAIL PROTECTED]> wrote:
>
>> Seems like you havn't format your cluster (if its 1st time made).
>>
>> On Fri, Nov 16, 2012 at 9:58 AM, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
>>
>>> Hi,
>>>
>>> Please help!
>>>
>>> I have installed a Hadoop Cluster with a single master (master1) and
>>> have HBase running on the HDFS.  Now I am setting up the second master
>>>  (master2) in order to form HA.  When I used JPS to check the cluster, I
>>> found :
>>>
>>> 2782 Jps
>>> 2126 NameNode
>>> 2720 SecondaryNameNode
>>> i.e. The datanode on this server could not be started
>>>
>>> In the log file, found:
>>> 2012-11-16 10:28:44,851 ERROR
>>> org.apache.hadoop.hdfs.server.datanode.DataNode: java.io.IOException:
>>> Incompatible namespaceIDs in /app/hadoop/tmp/dfs/data: namenode namespaceID
>>> = 1356148070; datanode namespaceID = 1151604993
>>>
>>>
>>>
>>> One of the possible solutions to fix this issue is to:  stop the
>>> cluster, reformat the NameNode, restart the cluster.
>>> QUESTION: As I already have HBASE running on the cluster, if I reformat
>>> the NameNode, do I need to reinstall the entire HBASE? I don't mind to have
>>> all data lost as I don't have many data in HBASE and HDFS, however I don't
>>> want to re-install HBASE again.
>>>
>>>
>>> On the other hand, I have tried another solution: stop the DataNode,
>>> edit the namespaceID in current/VERSION (i.e. set namespaceID=1151604993),
>>> restart the datanode, it doesn't work:
>>> Warning: $HADOOP_HOME is deprecated.
>>> starting master2, logging to
>>> /usr/local/hadoop-1.0.4/libexec/../logs/hadoop-hduser-master2-master2.out
>>> Exception in thread "main" java.lang.NoClassDefFoundError: master2
>>> Caused by: java.lang.ClassNotFoundException: master2
>>> at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
>>> at java.security.AccessController.doPrivileged(Native Method)
>>>  at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
>>> at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
>>>  at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
>>> at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>>> Could not find the main class: master2.  Program will exit.
>>> QUESTION: Any other solutions?
>>>
>>>
>>>
>>> Thanks
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>