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How To: Install Linux Kernel 3.18.1 in Ubuntu/Linux Mint Systems

The Linux Kernel 3.18.1 is now available for the users, announced Linus Torvalds. This Linux Kernel version comes with plenty of fixes and improvements. This article will guide you to install or upgrade to Linux Kernel 3.18.1 in your Ubuntu or Linux Mint system.


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How to setup a mail server with Postfix and Dovecot on Ubuntu / Debian

Mail system for your own domain You have your own domain name and your very own vps/dedicated server and want to use the domain name for emails. So you need to setup a mail server using an smtp server and an imap/pop server. This tutorial shows you how to setup Postfix (smtp server) and Dovecot (imap/pop server). The task of the smtp server is to accept incoming mails and relay outgoing mails from authorised users on the system. Whereas Dovecot allows authorized users to access their Inbox and...
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The Next Generation Penetration Testing Distro.

The most advanced, powerful and yet beautiful penetration testing distribution ever created.Lined up with ultimate collection of tools for pro Ethical Hackers and Cyber Security Experts.

Simplify security in your IT infrastructure with Cyborg. Its real strength comes from the understanding that a tester requires a strong and efficient system,that benefits from a strong selection of tools, integrated with a stable linux environment.




It has 700 + tools while other penetration distro have 300+ and also dedicated tools for and menu for mobile security and malware analysis . Also it is easy to compare it with others as to make a better OS than others ,we have to outperform them. 


Distro Features:-

*Exploitation Toolkit:- Toolkit to test the integrity of your IT Infrastructure.Best exploit of for best results

*Reverse Engineering:- Reversing the core code for the analysis by going backwards through the development cycle

*Forensics:- Uncover the Digital evidence. Investigate them and interpreting electronic data for use in a court of law.

*Stress Testing:- Determine the amount of stress your computer, network, program or device can bear.

*Mobile Security:- Penetrate the mobile security and fix the vulnerabilities of it . Mobile Security covers every known platform for smartphones.

*Wireless Security:- Secure your wireless world. Cyborg have top level tools to test your security.

















Howto Decorate Bash Prompt

The Bash shell provide users with a very customisable prompt through the variable named PS1 for the primary prompt and PS2 for the secondary prompt. This Howto is the basics to get started.

Simplest method to test changes to the prompt is by entering the following at the prompt and the immediate changes will be shown at the user prompt in the next press of the "Enter" key.

export PS1='Hello world$ '

This will display the words "Hello world$" followed by a space before the cursor.

Backslash-escaped Special Character

Users find it useful with their server hostname, user name, date, time, directory and all sorts of stuff displayed with their prompt. The list can be found at Bash Prompt from TLDP, here are listed a few;

  1. \d - the date  in  "Weekday  Month  Date"  format (e.g., "Tue May 26")
  2. \e - indicate an ASCII escape character (033)
  3. \h - the hostname up to the first '.'
  4. \n - newline
  5. \t - the current time in 24-hour HH:MM:SS format
  6. \T - the current time in 12-hour HH:MM:SS format
  7. \u - the username of the current user
  8. \W - the basename of the current working directory

Example 1: Common user name, server host name and working directory display

export PS1='[\u@\h \W]\$'

Example 2: Display current time and prompt in 2nd line

export PS1='\d [\u@\h \W]\n\t \$'


Font colour is a assigned with the sequence \[\e[colourcode\] where the colour code in combination of font style and ansi colour code (see TLDP). All colour escape sequences must be followed by letter 'm'.

Ansi colour code

  1. Black      0;30m
  2. Dark Gray     1;30m
  3. Blue        0;34m    
  4. Light Blue    1;34m
  5. Green       0;32m    
  6. Light Green   1;32m
  7. Cyan        0;36m    
  8. Light Cyan    1;36m
  9. Red         0;31m    
  10. Light Red     1;31m
  11. Purple      0;35m    
  12. Light Purple  1;35m
  13. Brown       0;33m    
  14. Yellow        1;33m
  15. Light Gray  0;37m    
  16. White         1;37m

\[\e[m\] Closing colour code

Example 1: Display common prompt as green and following character typed is also green. Its shown 2 ways of writing same prompt

export PS1='[\[\e[0;32m\]\u@\h \W]\$ 'export PS1='[\[\033[0;32m\]\u@\h \W]\$ '

Example 2: Display common prompt as green and following character typed is default colour

export PS1='[\[\e[0;32m\]\u@\h \W[\e[m\]]\$ '

Example 3: Contrast colours to highlight

export PS1='\[\e[1;34m\]\u\[\e[1;33m\]@\[\e[1;32m\]\h\[\e[1;37m\](\[\e[1;31m\]\W\[\e[1;37m\]) \[\e[1;36m\]\$ \[\e[0m\]'

Saving changes

Changes can be saved to ~/.bashrc to make sure that it is applied each time a user access the terminal.

To make this global, add the PS1 line to the /etc/bashrc. This however is always overridden by the user's ~/.bashrc configuration.

Example of ~/.bashrc:

# .bashrc# Source global definitions
if [ -f /etc/bashrc ]; then
    . /etc/bashrc
# User specific aliases and functions

What would become of this world if we could not share knowledge

We are living in an age where free flow of information has become vital to human progress. Information is free because is it believed that the more we share, the more we learn, the more we do. That is the open source philosophy. Make software free, not as in cost, but as in freedom to change and recreate. 

I personally do not want to live in a world that keeps valuable information that supports innovation behind bars. We learn from others. Ideas come in many forms. The more ideas implemented within a product, the more usefull and complex it becomes. Importantly, it never stops evolving. 

I am an avocate of sharing information, but under a specific category. The only information that I care to share and collect is technological information that either helps improve or develop new technological products or technological services. It is information that we all need and cannot live without. Decide for yourself. Invision a world without open source.


Why open source runs the world


Star Wars Luke Skywalker freecomputerdesktopwallpaper 1600





TCPdump Tutorial for Beginners

Tcpdump is a UNIX/Linux command line tool used to sniff and analyze network packets. Tcpdump offers similar functionality to that of the popular Wireshark application when used in command line mode and allows you to apply various filters to limit packet collection or packet output.

This is an introductory tutorial to tcpdump, filtering packets, as well as applying various filters and expressions.


Global Cloud Computing Virtualization Market Strategies, Shares & Forecasts 2016

Virtualization of software and servers creates ways to create more effective automated control of business process. The on-demand deployment model depends on the implementation of cloud computing. The ability to deploy virtual application images on any platform at any time has increased significantly. Business software as a service SaaS applications and cloud computing models have matured and adoption has become an issue for every IT department.

Private cloud systems provide security, response time, and service availability. Applications, platforms, and infrastructure are evolving separately. SaaS software as a service application is widely known by the computing model. Platform as a service (PaaS) and infrastructure as a service (IaaS) complement SaaS as compelling aspects of cloud computing and infrastructure services. An organization's application development team and the application portfolio need to be managed as a piecemeal part of the IT infrastructure. It is generally managed on an application by application basis. Applications represent a major source of IT value and are a large IT cost component.

Markets depend on virtualization to make information technology delivery a utility. On demand systems scale to meet the needs of users and users only pay for the capacity they use. Strategies relate to different ways to position software, hardware and services for the most effective product set. The 2010 study has 736 pages, 231 tables and figures.

The popularity of the on-demand deployment model has increased significantly. Systems provide security, response time, and service availability. SaaS software as a service application is widely known by the computing model illustrates. Business applications and computing models have matured and adoption has become an issue for every IT department. Platform as a service (PaaS) and infrastructure as a service (IaaS) have joined SaaS as compelling aspects of cloud computing applications and infrastructure services.

The IBM mainframe has the reliability, scalability, security, large block of memory, shared workload capability, and remote support capability needed in cloud computing. These are called the ity features. IBM mainframe leads enterprise cloud computing. IBM mainframe strategy seeks to permit users to utilize data, applications and services from any device and from any location based on open standards.

The IBM mainframe is able to virtualize new workload. The IFL virtualization provides a stable secure hosting environment for thousands of application images. IBM SOA cloud software is the leading integration system with 72% market share of a rapidly growing systems architecture. The code modules provide a way to make flexible systems that respond to changing market conditions.

Cisco virtualization is delivered through Unified Computing. As a premier networking company, Cisco has designed a compelling architecture that bridges the silos in the data center. A unified architecture uses industry standard technologies. Key to Cisco's approach is the ability to unite compute, network, storage access, and virtualization resources. A single energy efficient system can reduce IT infrastructure costs and complexity. It is used to extend capital assets and improve business agility.

Hewlett Packard High-performance computing (HPC) markets are powered by the adoption of Linux clusters. High-performance computing (HPC) markets are powered by the adoption of Linux clusters. Cluster complexity is rampant hardware parallelism: systems averaging thousands of processors, each of them a multi-core chip whose core count doubles every 18.24 months.

Hardware parallelism trend the additional issues of third-partysoftware costs, weak interconnect performance, the difficulty of scaling many applications beyond a single node, storage and data management, power, cooling, and facility space.

Cluster complexity quickly begins to skyrocket. Hewlett-Packard (HP) has the HPC cluster market share leadership position. Competitive advantage has been achieve principally by working to alleviate cluster complexity through a coordinated strategy of investment and innovation, HPC-centric product planning and design, external partnerships, application expertise and focus.

System integration, sales, and support are part of the HPC cluster solution. HP havs dominated the market by focusing on alleviating this complexity for datacenter administrators and end users. HP's broad product portfolio for HPC also leverages the company's innovations for the mainstream enterprise IT market and advances from HP Labs.

HP has taken a customer-centric, technology-agnostic approach that offers buyers a wide range of technology and product choices. The company has amassed the inhouse domain expertise needed to act as a trusted advisor to HPC users. HP has an innovative approach to the HPC market. The company is positioned to sustain its strong presence. The ability to exploit near-term growth trends depends on continuing to grow out the cluster capability leveraging virtualization.

The major management objectives for this critical area of applications implementation include improving service-oriented architecture (SOA) adoption, increasing Software Development Life Cycle (SDLC) efficiency, improving cost management, and reducing ineffective spending.

Get Sample Copy of Global Cloud Computing Virtualization Market Report @

The fundamental aspect of cloud applications implementation relates to flexibility. The ability to be responsive to changing market conditions is central to the modern IT management task. The desire for systems that support flexibility is anticipated to spur rapid growth of cloud computing. Cloud computing markets at $20.3 billion in 2009 are anticipated to reach $100.4 billion by 2016.


Fedora 21 VS Ubuntu 14.10 ( performance /User experience)

Hi Linuxites, 

would like to share my recent observations between Fedora 21 ( just released ) vs UBuntu 14.10. 

Configuration of my machine :: SONY VAIO VPCEB1E03, core i3 ( 1st generation), 8GB ram, 320gb HDD,

Background :: Just one week back installed Ubuntu 14.0 on my laptop by erasing windows 7.  Impressed with the  look and feel of Ubuntu, within few minutes able to use it.  Today installed fedora 21 official release on the same m/c by erasing Ubuntu 14.10.  My observations are like the following.  Just trying to settle down whether i have to go with UBuntu way or fedora way (?) .  Lets see what i have decided!!

Performance / User experience  ( UBuntu 14.10 vs Fedora 21-5 official release )

Ubuntu 14.10::

Looks impressive, Terminal window is beautifully coloured, graphics are good, heavy weight icons Seems, everything is OK, graphics drivers are installed no  issues.  But, I am facing few problems, like fan control always my FAN is running very fast and making noise, RAM is eaten up around 1.8 to 2.2 GB.  Started rhythm box music player, after playing sometime closed it. Executed top command, and it is showing still music player is running and utilizing CPU (??), I have to manually shut down the player.   Now, coming to application search box , when I type from keyboard my letters are being displayed very slowly, applications display is very very slow at this moment, my FAN makes so much noise.  Disabled web searching options in the settings, still i have same issues.  Software updates are installed without any issues.  GCC 4.9.1 is working fine.  kernel 3.16.x

Fedora 21-5 ( Official release ) ::

Instsalled, compared to Ubuntu installation seems this is fast.  everything is fine.  Now, repeated same actions from GNOME window manager.  graphics drivers are installed no issues.  surprisingly regarding FAN control, my fan is so silent and it is not making any noise, so so so quiet.  RAM is around 780MB is eaten up when I opened firefox, rhythm box music player and few terminals.  it was never above 1 GB.. thats impressive(same applications were opened with Ubuntu 14.10 also, it was RAM hungry 1.8 GB to 2.2GB).  applications are closed and immediately disappeared from my TOP command menu.  The surprising and I like very much is application search box.... Unlike in UBuntu Unity desktop search option, the Fedora 21 search is very fast , display is very fast, text input is very fast, i have tested really half an hour and seems, everything is awesome. FAN is not making any noise very quiet.  I havent even disabled web searching.  Software upadtes are installed without any issue.  Well, one awkward situation with fedora 21 is without using GNOME TWEAK TOOL, i cannot get my minimize and maximize buttons in terminal.  Fedora terminal windows are good,  but compared to Ubuntu terminals they are less attractivre. GCC 4.9.2 is working fine.  Kernel is 3.17.x

Conclusion :

I am a computer engineering graduate and software architect.  I thought i will stick to UBuntu because of its impressive looks.  But, due its resource hungry nature  and slow response times from desktop point of view, I think i will stick to FEDORA 21.  btw, I have two more laptops which run REDHAT ENTERPRISE LINUX 7.0 and SUSE ENTERPRISE LINUX 12.0 commercial versions, using core i7 and core i5 respectively .  RHEL 7.0 is more impressive from user experience point of view compared to all others.  

UBuntu applications and Fedora 21 applications are almost all are same.  Same packages, same utilities, i think I can do everything with both the versions from LINUX POINT OF VIEW. 

If UBUntu improves its response times with its window manager Unity , then it will become a great desktop compared to other versions.  Seems, UBuntu team is concentrating only on good looks without bothering about response times.  Their  team should concentrate on improving  response times. 

For the moment next 6 months, i will stick with fedora 21 only, Lets see what UBuntu 15.04 will come up with an answer to Fedora 21. 



How To : Install Linux Kernel 3.17.6 in Ubuntu/Linux Mint Systems

The Linux Kernel 3.17.6 is now available for the users, announced Linus Torvalds. This Linux Kernel version comes with plenty of fixes and improvements. This article will guide you to install or upgrade to Linux Kernel 3.17.6 in your Ubuntu or Linux Mint system.

Read complete article Here.


A beginner's guide to bash

A Brief Introduction
Bash or Bourne again shell is a replacement to the original unix shell written by Stephen Bourne at Bell Labs.

It offers vast improvements over the original shell, which include
Integer arithmetic,
Indexed arrays,
Command line editing,
Unlimited command history.

Bash scripts are available by default on most Linux distributions.


Send mail from command line on Linux using external SMTP server

SMTP servers If you have just setup an smtp server, like Postfix or Exim, then you would want to test it out to check if it is receiving and relaying emails properly or not. If you do not want to setup a mail client like Thunderbird on your local machine and want to run a quick command to send out mails via these smtp servers, then this post shows you how. 1. mailx command The mailx command is available from many different packages like mailutils,...
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