Linux ..some more advanced concepts :)

Apache - An Overview

● Most widely used web server on the planet

● Created by the creators of http protocol

● Over 65% market share● New protocol (waka) is

coming up – Apache 3.0

Apache – Features

● Multiple MPM– Prefork – Spawn process before they needed– Worker – For pure multi-threaded applications– Event – New, for multi-threaded applications

● Dynamic Module Loading– No need for recompilation, run time extensibility

● Virtual Hosting– Multiple web site on a single IP

Apache - Basics

Packages : httpd, httpd-devel

Start-up Script : /etc/init.d/httpd

Configuration Files : /etc/httpd/*, /var/www/*

Ports : 80 (http), 443 (https)

Daemon : /usr/sbin/httpd

Apache - Basics

Main Config File : /etc/httpd/conf/httpd.conf

Additional Modules : /etc/httpd/conf.d/*

Document Root : /var/www/html

Apache - Howto

● Installing apache● Basic Configuration● Enable / Disable Modules● Start / Stop / Monitor the web server● Configure PHP● Configure a test server with PHP and Apache

Virtual Hosting

Types of virtual hosts

– Name based

– Port Based

– Port Based

How to configure

# vi /etc/httpd/conf/httpd.conf

NameVirtualHost *:80

<VirtualHost *:80>

DocumentRoot /tmp/example.com

ServerName server.example.com

</VirtualHost>

<VirtualHost *:80>

DocumentRoot /tmp/test.com

ServerName server.test.com

</VirtualHost>

Mono

● An open Source C# and .NET development environment for Linux

● mod_mono : Apache 2.0/2.2 module that provides ASP.NET support for the web's favorite server, Apache.

Other web servers

● Lighttpd● Mongrel● Yaws

Reverse Proxies● Used for

● Caching● Security● Encryption● Load Distribution

● Examples● Nginx● Varnish● Squid

Databases

● Installing MySQL● Create a database● Install management

tools – phpMyAdmin● Install PostgreSQL

● Create a database● Install management

tools – phpPgAdmin

noSQL

● Not an RDBMS● No Table Schema● No joints● Very High Scalability – Horizontal● Used in high performance parallel computing● Examples

- Big Table, CouchDB, Cassandra, MongoDB

Types of file systems

● Disk File Systems

- Ext4, Ext3, ZFS, NTFS● FUSE – File System in User Space

- SSHFS, GlusterFS● Distributed / Parallel File Systems

- Luster, Google FS, Hadoop, MogileFS● Cluster File Systems

- GFS, OCFS, GPFS, CFS

Working on remote Server

● Ssh (secure shell)● Configure ssh server

● Automatic login

● Secure copy of files

● Remote command execution

● Rsync– Sync files between hosts– Widely used for backup

Cloud ComputingWhat is cloud computing

– You will get “Everything” As A Service

– Pay as per usage

– Dynamic Elasticity and Scalability

– High availability

Major Players

– Amazon

– RackSpace

Open Source Initiatives

– Open Stack

– Eucalyptus

– Open Nebula

VirtualizationWhat is Virtualization

Running multiple “instances” of OSs on a single machine

Types of virtualization

Full virtualization

Para virtualization

Advantages of virtulaization

Effective resource usage

Manageability

TCO

Linux Industry adoption● 99% of the Cloud platforms runs on Linux

● By 2014 Cloud will be a USD 10 Billion Business ● Mobile Application

● Andriod – Will dominate all other competition in coming future (Gartner Survey)

● All mission critical application

● Banking and Finance● Military● Space● Agriculture● Health

Careers In Linux

As a programmer● Java, Python, C, C++, Perl, SCALA, Ruby● MapReduce, Hyper Tables

As Administrator, Architect etc● Certification

– Red Hat (RHCE, RHCSS, RHCA)– Novell (CLP, CLE)– LPI (Level - 1, Level – 2, Level - 3)

Questions? Ask at www.iwillstudy.com/forum