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 <nkey...@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....@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....@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.
