sujee

<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
    <property>
        <name>mapreduce.framework.name</name>
        <value>yarn</value>
    </property>
</configuration>

sujee

<?xml version="1.0"?>
<configuration>
    <property>
        <name>yarn.resourcemanager.hostname</name>
        <value>localhost</value>
    </property>
    <property>
        <name>yarn.nodemanager.aux-services</name>
        <value>mapreduce_shuffle</value>
    </property>

sujee

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
    <property>
        <name>dfs.replication</name>
        <value>1</value>
        <description>single node, 1 copy</description>
    </property>
</configuration>

sujee

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
    <property>
        <name>fs.defaultFS</name>
        <value>hdfs://localhost:8020</value>
        <description>
            this replaces Hadoop 1 property : fs.default.name
        </description>
    </property>

sujee

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>mygroup</groupId> <!-- change this -->
    <artifactId>project_name</artifactId> <!-- change this -->
    <packaging>jar</packaging>
    <version>1.0</version>
    <name>Sample Project Name</name> <!-- change this -->

sujee

#!/bin/bash
hosts=$(cat $HADOOP_HOME/conf/slaves | grep -v '#')
for host in $hosts
do
    echo "------------------" $host "------------" 
    scp -o StrictHostKeyChecking=no  hadoop_hosts  $host:
    ssh -o StrictHostKeyChecking=no  root@$host "cat /etc/hosts.orig hadoop_hosts >> /etc/hosts"
done

sujee

#!/bin/bash
hosts=$(cat $HADOOP_HOME/conf/slaves | grep -v '#')
for host in $hosts
do
    echo "------------------" $host "------------" 
    ssh -o StrictHostKeyChecking=no  root@$host "cp /etc/hosts  /etc/hosts.orig"
done

sujee

// ---------- Bytes.add() : creating composite keys ---------
// rowkey = int + long
int i = 0;
long timestamp = System.currentTimeMillis();
byte [] rowkey2 = Bytes.add(Bytes.toBytes(i), Bytes.toBytes(timestamp));
System.out.println ("rowkey2 (" + rowkey2.length + ") : " + Arrays.toString(rowkey2));

// add also supports adding 3 byte arrays
// rowkey = int + str + long
byte[] rowkey3 = Bytes.add(Bytes.toBytes(0) , Bytes.toBytes("hello"),  Bytes.toBytes(timestamp)); 

sujee

 // -------- Bytes.toBytes() : converting objects to bytes ------
int i = 10000;
byte [] intBytes = Bytes.toBytes(i);
System.out.println ("int " + i + " in bytes : " + Arrays.toString(intBytes));
            
float f = (float) 999.993;
byte [] floatBytes = Bytes.toBytes(f);
System.out.println ("float " + f + " in bytes : " + Arrays.toString(floatBytes));
            
String s = "foobar";

sujee

package sujee;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.mapred.ClusterStatus;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;