hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Venkateswara Rao Dokku <dvrao....@gmail.com>
Subject Re: Hbase clustering
Date Thu, 27 Sep 2012 07:39:54 GMT
On Thu, Sep 27, 2012 at 1:09 PM, Venkateswara Rao Dokku <dvrao.584@gmail.com
> wrote:

> I can see that HMaster is not started on the data-node machine when the
> start scripts in hadoop & hbase ran on the hadoop-namenode. My doubt is
> that,Shall we have to start that master on the hadoop-datanode1 too or the
> hadoop-datanode1 will access the Hmaster that is running on the
> hadoop-namenode to create,list,scan tables as the two nodes are in the
> cluster as namenode & datanode.
>
>
> On Thu, Sep 27, 2012 at 1:02 PM, n keywal <nkeywal@gmail.com> wrote:
>
>> 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.
>> >
>>
>
>
>
> --
> 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.

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message