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From n keywal <nkey...@gmail.com>
Subject Re: Hbase clustering
Date Thu, 27 Sep 2012 07:32:39 GMT
Hi,

I would like to direct you to the reference guide, but I must acknowledge
that, well, it's a reference guide, hence not really easy for a plain new
start.
You should have a look at Lars' blog (and may be buy his book), and
especially this entry:
http://www.larsgeorge.com/2009/10/hbase-architecture-101-storage.html

Some hints however:
- the replication occurs at the hdfs level, not the hbase level: hbase
writes files that are split in hdfs blocks that are replicated accross the
datanodes. If you want to check the replications, you must look at what
files are written by hbase and how they have been split in blocks by hdfs
and how these blocks have been replicated. That will be in the hdfs
interface. As a side note, it's not the easiest thing to learn when you
start :-)
- The error > ERROR: org.apache.hadoop.hbase.MasterNotRunningException:
Retried 7 times
  this is not linked to replication or whatever. It means that second
machine cannot find the master. You need to fix this first. (googling &
checking the logs).


Good luck,

Nicolas




On Thu, Sep 27, 2012 at 9:07 AM, Venkateswara Rao Dokku <dvrao.584@gmail.com
> wrote:

> How can we verify that the data(tables) is distributed across the cluster??
> Is there a way to confirm it that the data is distributed across all the
> nodes in the cluster.?
>
> On Thu, Sep 27, 2012 at 12:26 PM, Venkateswara Rao Dokku <
> dvrao.584@gmail.com> wrote:
>
> > Hi,
> >     I am completely new to Hbase. I want to cluster the Hbase on two
> > nodes.I installed hadoop,hbase on the two nodes & my conf files are as
> > given below.
> > *cat  conf/regionservers *
> > hbase-regionserver1
> > hbase-master
> > *cat conf/masters *
> > hadoop-namenode
> > * cat conf/slaves *
> > hadoop-datanode1
> > *vim conf/hdfs-site.xml *
> > <?xml version="1.0"?>
> > <?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
> >
> > <!-- Put site-specific property overrides in this file. -->
> >
> > <configuration>
> > <property>
> >         <name>dfs.replication</name>
> >         <value>2</value>
> >         <description>Default block replication.The actual number of
> > replications can be specified when the file is created. The default is
> used
> > if replication is not specified in create time.
> >         </description>
> > </property>
> > <property>
> >         <name>dfs.support.append</name>
> >         <value>true</value>
> >         <description>Default block replication.The actual number of
> > replications can be specified when the file is created. The default is
> used
> > if replication is not specified in create time.
> >         </description>
> > </property>
> > </configuration>
> > *& finally my /etc/hosts file is *
> > 127.0.0.1       localhost
> > 127.0.0.1       oc-PowerEdge-R610
> > 10.2.32.48  hbase-master hadoop-namenode
> > 10.240.13.35 hbase-regionserver1  hadoop-datanode1
> >  The above files are identical on both of the machines. The following are
> > the processes that are running on my m/c's when I ran start scripts in
> > hadoop as well as hbase
> > *hadoop-namenode:*
> > HQuorumPeer
> > HMaster
> > Main
> > HRegionServer
> > SecondaryNameNode
> > Jps
> > NameNode
> > JobTracker
> > *hadoop-datanode1:*
> >
> > TaskTracker
> > Jps
> > DataNode
> > -- process information unavailable
> > Main
> > NC
> > HRegionServer
> >
> > I can able to create,list & scan tables on the *hadoop-namenode* machine
> > using Hbase shell. But while trying to run the same on the  *
> > hadoop-datanode1 *machine I couldn't able to do it as I am getting
> > following error.
> > hbase(main):001:0> list
> > TABLE
> >
> >
> > ERROR: org.apache.hadoop.hbase.MasterNotRunningException: Retried 7 times
> >
> > Here is some help for this command:
> > List all tables in hbase. Optional regular expression parameter could
> > be used to filter the output. Examples:
> >
> >   hbase> list
> >   hbase> list 'abc.*'
> > How can I list,scan the tables that are created by the *hadoop-namenode *
> > from the *hadoop-datanode1* machine. Similarly Can I create some tables
> > on  *hadoop-datanode1 *& can I access them from the *hadoop-namenode * &
> > vice-versa as the data is distributed as this is a cluster.
> >
> >
> >
> > --
> > Thanks & Regards,
> > Venkateswara Rao Dokku,
> > Software Engineer,One Convergence Devices Pvt Ltd.,
> > Jubille Hills,Hyderabad.
> >
> >
>
>
> --
> Thanks & Regards,
> Venkateswara Rao Dokku,
> Software Engineer,One Convergence Devices Pvt Ltd.,
> Jubille Hills,Hyderabad.
>

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