Installing Ambari from scratch using Vagrant. Step by Step

Being a developer it a pain to configure hadoop every time.
I wanted a process that is easily reproducible.
So at a high level steps involved are:

	# FDQN
	# Password Less SSH, Disable SELINUX , iptables Off
	# NTP
	# yum -y install ntp
	# wget http://public-repo-1.hortonworks.com/ambari/centos6/1.x/updates/1.5.1/ambari.repo
	# cp ambari.repo /etc/yum.repos.d
	# yum install ambari-server
	# ambari-server setup
	# ambari-server start
	# Start Ambari in browser u/n admin , pwd admin
	# If Somthing Goes Wrong
	#‘yum erase ambari-agent’ and ‘yum erase ambari-server’

view raw ambari hosted with ❤ by GitHub

Make sure you have vagrant installed
Config : 3 node , 3.4GB, 1 core each
1 master, 2 slaves
Create a vagrant file (Make sure you have more than 10GB Ram)

	Vagrant::Config.run do |config|
	config.vm.box = "centos65"
	config.vm.customize [
	"modifyvm", :id,
	"--memory", "3427"
	]
	config.vm.define :hadoop1 do |hadoop1_config|
	hadoop1_config.vm.network :hostonly, "10.10.0.53"
	hadoop1_config.vm.host_name = "hdp.hadoop1.com"
	end
	config.vm.define :hadoop2 do |hadoop2_config|
	hadoop2_config.vm.network :hostonly, "10.10.0.54"
	hadoop2_config.vm.host_name = "hdp.hadoop2.com"
	end
	config.vm.define :hadoop3 do |hadoop3_config|
	hadoop3_config.vm.network :hostonly, "10.10.0.55"
	hadoop3_config.vm.host_name = "hdp.hadoop3.com"
	end
	end

view raw Vagrantfile hosted with ❤ by GitHub

after creating this file all you need to do is 'vagrant up'

Step 1: FDQN
http://en.wikipedia.org/wiki/Fully_qualified_domain_name
change vi /etc/hosts

prepend with following entries
10.10.0.53   hdp.hadoop1.com hadoop1
10.10.0.54   hdp.hadoop2.com hadoop2
10.10.0.55   hdp.hadoop3.com hadoop3

(In All three nodes)
you should be able to ssh using domain names + 'hostname -f' returns fdqn for that machine

Install NTP and NTPD in all nodes

Use the script below to prepare your cluster
./prepare-cluster.sh hosts.txt

	hdp.hadoop1.com
	hdp.hadoop2.com
	hdp.hadoop3.com

view raw host hosted with ❤ by GitHub

	#!/bin/bash
	set -x
	# Generate SSH keys
	ssh-keygen -t rsa
	cd ~/.ssh
	cat id_rsa.pub >> authorized_keys
	cd ~
	# Distribute SSH keys
	for host in `cat hosts.txt`; do
	cat ~/.ssh/id_rsa.pub | ssh root@$host "mkdir -p ~/.ssh; cat >> ~/.ssh/authorized_keys"
	cat ~/.ssh/id_rsa | ssh root@$host "cat > ~/.ssh/id_rsa; chmod 400 ~/.ssh/id_rsa"
	cat ~/.ssh/id_rsa.pub | ssh root@$host "cat > ~/.ssh/id_rsa.pub"
	done
	# Distribute hosts file
	for host in `cat hosts.txt`; do
	scp /etc/hosts root@$host:/etc/hosts
	done
	# Prepare other basic things
	for host in `cat hosts.txt`; do
	ssh root@$host "sed -i s/SELINUX=enforcing/SELINUX=disabled/g /etc/selinux/config"
	ssh root@$host "chkconfig iptables off"
	ssh root@$host "/etc/init.d/iptables stop"
	echo "enabled=0" | ssh root@$host "cat > /etc/yum/pluginconf.d/refresh-packagekit.conf"
	done

view raw prepare-cluster hosted with ❤ by GitHub

And Vola . Just run the commands below.

	# wget http://public-repo-1.hortonworks.com/ambari/centos6/1.x/updates/1.5.1/ambari.repo
	# cp ambari.repo /etc/yum.repos.d
	# yum install ambari-server
	# ambari-server setup
	# ambari-server start
	# Start Ambari in browser u/n admin , pwd admin

view raw Ambari hosted with ❤ by GitHub

PS : Make sure you had entries to the hosts in Windows. Remember to check if the hostname is pingable from windows.

ping hdp.hadoop1.com

URL : hdp.hadoop1.com:8080

MapR SingleNode in Ubuntu

Creating a single node instance of MapR in ubuntu.

	# Navigate to this Folder
	cd /etc/apt
	# Edit sources.list file and add the MapR repositories into it.
	vi sources.list
	# Add MapR repo entries below
	deb http://package.mapr.com/releases/v2.1.2/ubuntu/ mapr optional
	deb http://package.mapr.com/releases/ecosystem/ubuntu binary/
	# Update repo
	sudo apt-get update
	# install Map-r hadoop
	sudo apt-get install mapr-single-node

view raw Mapr hosted with ❤ by GitHub

Using Pig to Load and Store data from HBase

Lets first store data from HDFS to our HBase Table. For this we will be using

org.apache.pig.backend.hadoop.hbase
Class HBaseStorage

public HBaseStorage(String columnList) throws org.apache.commons.cli.ParseException,IOException)

Warning: Make sure that your PIG_CLASSPATH refers to all the library files in HBASE,HADOOP and ZOOKEEPER. Doing this will save you countless hours of debugging.

Lets Create a HBase table for the data given below named as testtable.

Make sure that your first column is the ROWKEY while doing an insert to HBase table.

	1|Krishna|23
	2|Madhuri|37
	3|Kalyan|54
	4|Shobhana|50

view raw HBase hosted with ❤ by GitHub

Lets Create a Table for this data in HBase.

>> cd $HBASE_HOME\bin
>> ./hbase shell

This will take you to your HBase shell

>> create 'testtable','cf'
>> list 'testtable'
>> scan 'testtable'

Now lets fire up grunt shell

Type in the following commands in the grunt shell

	-- Loading the testdata to your relation
	A = LOAD '/home/biadmin/testdata' using PigStorage('|') as (id,name,age);
	-- Casting to chararray needs to be done
	B = foreach A generate (chararray)$0,(chararray)$1,(chararray)$2;
	-- We can delemit by either space or comma
	C = STORE B INTO 'hbase://testtable' USING org.apache.pig.backend.hadoop.hbase.HBaseStorage('cf:name cf:age');

view raw gistfile1.txt hosted with ❤ by GitHub

and TaDa....

Pig Casting and Schema Management

Pig is quite flexible when schema need to be manipulated.

Consider this data set

	a,1,55,M,IND
	b,2,55,M,US
	c,3,56,F,GER
	d,4,57,F,AUS

view raw Schema hosted with ❤ by GitHub

Suppose we needed to define schema after some processing we could cast the columns with their data types

	-- Load
	A = load 'input' using PigStorage(',');
	-- this will generate all columns after the first one
	B = foreach A generate $1..;
	--Suppose you need to cast the
	C = FOREACH A generate (chararray)$0,(int)$1,(int)$2,(chararray)$3,(chararray)$4;
	dump C;

view raw Cast hosted with ❤ by GitHub

That all for today folks.

Cheers!

Sum in Pig

This is a simple PigScript i wrote to understand the concepts of pig.
Well here it goes

Today we will see how to do a simple sum operation in Pig.

Consider this as my input data

	1
	2
	3
	4
	1
	1
	1

view raw input hosted with ❤ by GitHub

.

The first example - sum
The second example - group and sum

	-- Plain Sum
	B = group A All;
	C = foreach B generate SUM($1);
	dump C;
	-- Group And Sum
	A = load 'input' as (number:int);
	B = group A by $0;
	C = foreach B generate SUM($1);
	dump C;

view raw Sum hosted with ❤ by GitHub

Installing R with RStudio in Ubuntu

Helllo people,

lets start the installation by opening your terminal first.

and type in the flowering commands.

sudo apt-get install r-base

sudo apt-get install gdebi-core

sudo apt-get install libapparmor1

wget http://download2.rstudio.org/rstudio-server-0.98.1085-amd64.deb

sudo gdebi rstudio-server-0.98.1085-amd64.deb

and here you go with a brand new R-Studio.

Apache Pig Day 1

Hello People,
I increasingly spending more time working on pig. (Thankgod).
This experience has been very valuable as it has increased my knowledge on data.
Pig is an open source project.
Language for developing pig scripts is called pig latin.
Its easier to write pig script than mapreduce code (Its saves the developers time)
Pig is a dataflow language that means it allows the users to describe data.
Pig Latin Scripts are describes a DAG. Directed Acyclic Graph
Developed by Yahoo!.
Aim to this language is to find a sweet spot between SQL and Shell Scripts.
To sum it up Pig is you to build data pipelines / run ETL workloads.
 

TO DO List

This order is of importance...
a) Data Structures and Algorithms
b) Machine Learning
c) Dev Ops (Linux)
d) Start a youtube channel
e) Spring Framework Learn

I guess this will take a life time to master.

Currently preparing for Hadoop Admin Certification.

Pig

I will posting series of posts on Pig.

I personally feel amazed at the simplicity and the power of this language.

Pig Cheat Sheet:

http://mortar-public-site-content.s3-website-us-east-1.amazonaws.com/Mortar-Pig-Cheat-Sheet.pdf

Cheers!

Krishna

Crawling - Scrapy

What is Scrapy?

Scrapy is a fast high-level screen scraping and web crawling framework, used to crawl websites and extract structured data from their pages. It can be used for a wide range of purposes, from data mining to monitoring and automated testing.

Installation

OS Ubuntu

Installing Dependencies 

sudo apt-get install build-essential libssl-dev libffi-dev python-dev

Install scrapy

sudo pip install Scrapy

The above scripts will install scrapy

Algorithms

I am taking algorithms course in coursera.

Python week 4

Week 4 of coursera.
Been busy with odd jobs just not able to finish the assignments and be done with it.
I hope to complete all video lectures and assignments today.

Julia Meetup

I had an amazing experience organizing the first Julia meetup in Inmobi with Abhijit and Kiran.
Gave my first formal open source talk and it felt great.
Link to my slides - http://www.slideshare.net/KrishnaKalyan3/julia-meetup-bangalore

Distributed Cache - Pig

I had been trying to use Distributed-Cache in Pig.
After a lot of trial and errors behold SUCCESS!
Lets get to the meat.

	package UDF;
	import java.io.BufferedReader;
	import java.io.FileReader;
	import java.io.IOException;
	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map.Entry;
	import java.util.regex.Matcher;
	import java.util.regex.Pattern;
	import org.apache.hadoop.fs.Path;
	import org.apache.pig.EvalFunc;
	import org.apache.pig.backend.executionengine.ExecException;
	import org.apache.pig.data.Tuple;
	import org.apache.pig.impl.util.WrappedIOException;
	public class Regex extends EvalFunc<String> {
	static HashMap<String, String> map = new HashMap<String, String>();
	public List<String> getCacheFiles() {
	Path lookup_file = new Path(
	"hdfs://localhost.localdomain:8020/user/cloudera/top");
	List<String> list = new ArrayList<String>(1);
	list.add(lookup_file + "#id_lookup");
	return list;
	}
	public void VectorizeData() throws IOException {
	FileReader fr = new FileReader("./id_lookup");
	BufferedReader brd = new BufferedReader(fr);
	String line;
	while ((line = brd.readLine()) != null) {
	String str[] = line.split("#");
	map.put(str[0], str[1]);
	}
	fr.close();
	}
	private String Regex(String tweet) throws ExecException {
	// TODO Auto-generated method stub
	for (Entry<String, String> entry : map.entrySet()) {
	Pattern r = Pattern.compile(map.get(entry.getKey()));
	Matcher m = r.matcher(tweet);
	if (m.find() == true) {
	return entry.getValue();
	}
	}
	return null;
	}
	public String exec(Tuple input) throws IOException {
	if (input == null || input.size() < 1 || input.get(0) == null)
	return null;
	try {
	VectorizeData();
	String str = (String) input.get(0);
	return Regex(str);
	} catch (Exception e) {
	throw WrappedIOException.wrap(
	"Caught exception processing input row ", e);
	}
	}
	}

view raw gistfile1.txt hosted with ❤ by GitHub

Lets go through the steps.
a)Create an Eval UDF
b)Initialize Distributed Cache using getCachedFiles()
c)Initialize the Data Structure using step b.
d)Finally apply your logic on the data.

Python Week 3

Week 3 was easy. I also managed to score a whooping 92% in the test.

I am enjoying the mini assignments. Hope to complete every thing.

Cheers!

Krishna

Python Week 2

I completed the mini project however i forgot to give my weekly quiz :( . I was mad at my self for doing this after long research i found that i would be loosing around ~2% from my final score.

:(

Learning Python

Just for the record i am a big fan of python. Main reason my frustration with JAVA.
I am taking the interactive python course in Coursera.
Just finished week 0.
Wish me luck. I want to complete at least 1 MOOC fully.
Will post weekly updates on how it goes.

HBase

I have always excited with the NOSQL hype. End result HBase certification.
I took up the cloudera certification.

My thoughts:
It was a good investment of time and money.
Really exposes you to BigData NoSql Space.
It improved my over understanding of the NoSQL BigData Eco-System.

Now off to prepare for the Cloudera Admin Program.

Cheers!! 

Using Sublime Text - JULIA (Ubuntu)

Installing Sublime Text 2

sudo add-apt-repository ppa:webupd8team/sublime-text-3
sudo apt-get update
sudo apt-get install sublime-text-installer


Run Julia
julia
Pkg.add("ZMQ")
Pkg.add("IJulia")


And then follow the steps in this Site:
https://github.com/karbarcca/Sublime-IJulia