sankars

## execute hbase commands from bash

echo list | hbase shell

echo list \'1012\' | hbase shell


## View contents of HFile

sankars

# Installing CDH4 on a Single Linux Node in Pseudo-distributed Mode
# https://ccp.cloudera.com/display/CDH4DOC/Installing+CDH4+on+a+Single+Linux+Node+in+Pseudo-distributed+Mode

# Installing CDH4 with MRv1 on a Single Linux Node in Pseudo-distributed mode
# On Ubuntu and other Debian systems
nipra@lambda:Downloads$ wget -cv http://archive.cloudera.com/cdh4/one-click-install/precise/amd64/cdh4-repository_1.0_all.deb
nipra@lambda:Downloads$ sudo dpkg -i cdh4-repository_1.0_all.deb # Adds /etc/apt/sources.list.d/cloudera-cdh4.list ??
nipra@lambda:Downloads$ dpkg -L cdh4-repository                  # To view the files on Ubuntu systems

# Install CDH4

sankars

Install Java JDK 6.0 update 31 on Ubuntu 12.04 LTS

Introduction
The first question is why are we installing an old JDK. The answer is that Oracle JDK 6.0 update 31 is the JDK recommended by Cloudera when installing CDH4 (Cloudera Distribution Hadoop v4).

This is an update to an older version of this post. Mainly I have changed the JDK from 1.6.0_26 to 1.6.0_31 as this is the recommended JDK for CDH4 .

Install Java
I have a 64 bit version of Ubuntu 12.04 LTS installed, so the instructions below only apply to this OS.

sankars

##########
# For verification, you can display the OS release.
##########
$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=11.10
DISTRIB_CODENAME=oneiric
DISTRIB_DESCRIPTION="Ubuntu 11.10"

##########

sankars

=================================================================
SETTING UP SSHD AS A SERVICE FOR RUNNING HADOOP DAEMONS ON WINDOWS 7
=================================================================

Steps:

1. Download 'setup.exe' from Cygwin website
2. Right-click on 'setup.exe' 
3. Leave settings as they are, click through until you come to the plugin selection window
	3.1 - Make sure that the installation directory is 'C:\cygwin'

sankars

hbase org.apache.hadoop.hbase.util.RegionSplitter test_table HexStringSplit -c 10 -f f1

sankars

## To load

disable 'Table'
alter 'Table', METHOD => 'table_att', 'COPROCESSOR' => '/path/to/coprocessors.jar|com.org.xxxx.Coprocessorclass|3|'
enable 'Table'

## To check coprocessor is loaded

describe 'Table'

sankars

for i in '0'..'9' do for j in '0'..'9' do \
for k in '0'..'9' do put 'testtable', "row-#{i}#{j}#{k}", \
"colfam1:#{j}#{k}", "#{j}#{k}" end end end

sankars

public class TestCoprocessor extends BaseRegionObserver{

    private HTablePool pool = null;

    private final static String  INDEX_TABLE  = "INDEX_TBL";
    private final static String  SOURCE_TABLE = "SOURCE_TBL";

    @Override
    public void start(CoprocessorEnvironment env) throws IOException {  
        pool = new HTablePool(env.getConfiguration(), 10);

sankars

## @CDH3

hadoop jar hbase-0.90.6-cdh3u4.jar export table_name /exports/directory_name

## @CDH4

hadoop fs -cp  hftp://cdh3_namenode:50070/ /exports

hadoop jar $HBASE_HOME/hbase-0.94.6-cdh4.3.0-security.jar import table_name /exports/directory_name