Connecting Hbase using Java

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Installing Pseudo- Distributed HBase on Ubuntu

HBase run modes: Standalone and Distributed

Standalone mode: By default HBase runs in standalone mode. In standalone mode, HBase does not use HDFS. 

Distributed mode: Distributed mode can be subdivided into distributed but all daemons run on a single node is pseudo-distributed— and fully-distributed where the daemons are spread across all nodes in the cluster.

Hadoop version support matrix

HBase-0.92.x HBase-0.94.x HBase-0.95
Hadoop-0.20.205

S

X

X

Hadoop-0.22.x

S

X

X

Hadoop-1.0.0-1.0.2[a]

S

S

X

Hadoop-1.0.3+

S

S

S

Hadoop-1.1.x

NT

S

S

Hadoop-0.23.x

X

S

NT

Hadoop-2.x

X

S

S

[a] HBase requires hadoop 1.0.3 at a minimum; there is an issue where we cannot find KerberosUtil compiling against earlier versions of Hadoop.

Where

S = supported and tested,
X = not supported,
NT = it should run, but not tested enough.

Pseudo- Distributed Installation

The hbase-0.94.8 installation is done in below versions of Linux, Java and Hadoop respectively.

UBUNTU 13.4

JAVA 1.7.0_25

HADOOP 1.1.2

I have hduser as a dedicated hadoop system user. I had installed my Hadoop in /home/hduser/hadoop folder. Now I am going to install hbase in /usr/lib/hbase folder.

  • Download hbase<version>.tar.gz stable version from here
  • Enter into the directory where the stable version is downloaded. By default it downloads in “Downloads” directory
$ cd Downloads/
  • Unzip the tar file.
$ tar -xvf hbase-0.94.8.tar.gz
  • Create directory
$ sudo mkdir /usr/lib/hbase
  • move  hbase-0.94.8 to hbase
$ mv hbase-0.94.8 /usr/lib/hbase/hbase-0.94.8
  • Open your hbase/conf/hbase-env.sh and modify these lines
export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_25

export HBASE_REGIONSERVERS=/usr/lib/hbase/hbase-0.94.8/conf/regionservers

export HBASE_MANAGES_ZK=true
  • Set the HBASE_HOME path in bashrc file

To open bashrc file use this command

$ gedit ~/.bashrc

In bashrc file append the below 2 statements

export HBASE_HOME=/usr/lib/hbase/hbase-0.94.8

export PATH=$PATH:$HBASE_HOME/bin

 

  • Update hbase-site.xml in HBASE_HOME/conf folder with required properties.

    hbase-site.xml

<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>

<configuration>

<property>

<name>hbase.rootdir</name>

<value>hdfs://localhost:9000/hbase</value>

</property>

<property>

<name>hbase.cluster.distributed</name>

<value>true</value>

</property>

<property>

<name>hbase.zookeeper.quorum</name>

<value>localhost</value>

</property>

<property>

<name>dfs.replication</name>

<value>1</value>

</property>

<property>

<name>hbase.zookeeper.property.clientPort</name>

<value>2181</value>

</property>

<property>

<name>hbase.zookeeper.property.dataDir</name>

<value>/home/hduser/hbase/zookeeper</value>

</property>

</configuration>
  • Now check Hadoop version support matrix. If Hadoop is not supported your hbase version then you will get some exception. To fix this simply copy hadoop-core-*.jar from your HADOOP_HOME and commons-collections-*.jar from HADOOP_HOME/lib folder into your HBASE_HOME/lib folder.
  • Extra steps

In /etc/hosts there are two entries:127.0.0.1 and 127.0.1.1.Change the second entry 127.0.1.1 to 127.0.0.1  otherwise it gives error: org.apache.hadoop.hbase.PleaseHoldException: Master is initializing

  • To start Hbase [ First start hadoop ]
hduser@archana:~$ start-hbase.sh

localhost: starting zookeeper, logging to /usr/lib/hbase/hbase-0.94.8/bin/../logs/hbase-hduser-zookeeper-archana.out
 starting master, logging to /usr/lib/hbase/hbase-0.94.8/logs/hbase-hduser-master-archana.out
 localhost: starting regionserver, logging to /usr/lib/hbase/hbase-0.94.8/bin/../logs/hbase-hduser-regionserver-archana.out

jps command list down all currently running processes

hduser@archana:~$ jps

 4334 HQuorumPeer
 2882 SecondaryNameNode
 4867 Jps
 3207 TaskTracker
 2460 NameNode
 4671 HRegionServer
 4411 HMaster
 2977 JobTracker
 2668 DataNode

Hbase Shell

hduser@archana:~$ hbase shell

HBase Shell; enter 'help<RETURN>' for list of supported commands.
 Type "exit<RETURN>" to leave the HBase Shell
 Version 0.94.8, r1485407, Wed May 22 20:53:13 UTC 2013

hbase(main):001:0> create 't1','c1'
  • To stop HBase
HBASE_PATH$ bin/stop-hbase.sh

stopping hbase...............

To use the web interfaces

http://localhost:60010 for master
http://localhost:60030 for region server

  • Reference :

http://hbase.apache.org/book/standalone_dist.html

http://hbase.apache.org/book/standalone_dist.html#confirm

Note:The information provided here is best of my knowledge and experience if at all any modifications are to be made please help me with ur valuable suggestion which are always welcome…. :)

Installing Apache HBase on Ubuntu for Standalone Mode

Standalone HBase

By default HBase runs in standalone mode. In standalone mode, HBase does not use HDFS — it uses the local file system instead — and it runs all HBase daemons and a local zookeeper all up in the same JVM. Zookeeper binds to a well-known port so clients may talk to HBase. HBase requires java 6 or newer version. If this is not the case, HBase will not start.

The hbase-0.94.8 installation is done in below versions of Linux, Java and Hadoop respectively.

UBUNTU 13.4

JAVA 1.7.0_25

HADOOP 1.1.2

I have hduser as a dedicated hadoop system user. I had installed my Hadoop in /home/hduser/hadoop folder. Now I am going to install hbase in /usr/lib/hbase folder.

  • Download hbase-0.94.8.tar.gz from here
  • Enter into the directory where the stable version is downloaded. By default it downloads in “Downloads” directory
$ cd Downloads/
  • Unzip the tar file.
$ tar -xvf hbase-0.94.8.tar.gz
  • Create directory
$ sudo mkdir /usr/lib/hbase
  • move  hbase-0.94.8 to hbase
$ mv hbase-0.94.8 /usr/lib/hbase/hbase-0.94.8
  • Configuring HBase with java

Open your hbase/conf/hbase-env.sh and set the path to the java installed in your system

export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_25
  • Set the HBASE_HOME path in bashrc file

To open bashrc file use this command

hduser@system_name:~$ gedit ~/.bashrc

In bashrc file append the below 2 statements

export HBASE_HOME=/usr/lib/hbase/hbase-0.94.8

export PATH=$PATH:$HBASE_HOME/bin
  •  At this point, you are ready to start HBase. But before starting it, you might want to edit conf/hbase-site.xml and set the directory you want HBase to write to, hbase.rootdir.
  •  By default, hbase.rootdir is set to /tmp/hbase-${user.name} which means you’ll lose all your data whenever your server reboots
  •  So replace DIRECTORY in the hbase-site.xml with a path to a directory where you want HBase to store its data.
  •  hbase-site.xml
<?xml version="1.0"?>

<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>

<configuration>

<property>

<name>hbase.rootdir</name>

<value>file:///home/hduser/HBASE/hbase</value>

</property>

<property>

<name>hbase.zookeeper.property.dataDir</name>

<value>/home/hduser/HBASE/zookeeper</value>

</property>

</configuration>
  • Extra steps

In /etc/hosts there are two entries:127.0.0.1 and 127.0.1.1.Change the second entry 127.0.1.1 to 127.0.0.1  otherwise it gives error: org.apache.hadoop.hbase.PleaseHoldException: Master is initializing

  • To start Hbase [ in standalone mode no need to start hadoop ]
HBASE_PATH$bin/start-hbase.sh

HBASE_PATH$ bin/hbase shell
  • To stop HBase
HBASE_PATH$ bin/stop-hbase.sh

stopping hbase...............
  • To use the web interfaces

http://localhost:60010 for master
http://localhost:60030 for region server

  • Reference :

http://archive.cloudera.com/cdh/3/hbase-0.90.1-cdh3u0/quickstart.html

http://archive.cloudera.com/cdh/3/hbase-0.90.1-cdh3u0/notsoquick.html

Note:The information provided here is best of my knowledge and experience if at all any modifications are to be made please help me with ur valuable suggestion which are always welcome…. :)

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