Home | About | Sematext search-lucene.com search-hadoop.com
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB
 Search Hadoop and all its subprojects:

Switch to Plain View
HDFS >> mail # user >> Re: High Availability - second namenode (master2) issue: Incompatible namespaceIDs


+
hadoop hive 2012-11-16, 07:45
+
shashwat shriparv 2012-11-16, 07:52
Copy link to this message
-
Re: High Availability - second namenode (master2) issue: Incompatible namespaceIDs
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
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB