Understanding Fedora, Redhat and CentOS

Talking about Linux Distribution these three are quite famous for maintaining the server and security perspectives. I don't mean to say there are only these three distributions for servers and network security, I would absolutely be wrong. In that case Slackware, Arch, Black Arch, Kali, Bodhi are some name which shouldn't be missed. I agree there are even more. But being interrelated with each other, people generally get confused about following three Linux Distributions: 

  • Fedora
  • Redhat
  • CentOS
They get confused regarding following points:
  •  Do they belong to same company?
  • As Redhat is available as a commercial version do other distributions cost money as well?
  • Who maintains them?
  • How  often their stable versions are released?

I was also little unclear previously, so I did a little study about these three distribution and went through wikipedia. Being convinced myself I draw this diagram listing their features in order top to button.

I wish this will  somehow help.


Do you think Ubuntu spies on you?

Answer: Yes it does I will show you how it does. I found out this said by Richard Stallman.

Free Software Foundation President Richard Stallman called Ubuntu Linux "spyware" because the operating system sends data to Ubuntu maker Canonical when a user searches the desktop.

"Ubuntu, a widely used and influential GNU/Linux distribution, has installed surveillance code," Stallman wrote in a post titled "Ubuntu Spyware: What to Do?" "When the user searches her own local files for a string using the Ubuntu desktop, Ubuntu sends that string to one of Canonical's servers. … Ubuntu uses the information about searches to show the user ads to buy various things from Amazon. Amazon commits many wrongs (see http://stallman.org/amazon.html); by promoting Amazon, Canonical contributes to them. However, the ads are not the core of the problem. The main issue is the spying. Canonical says it does not tell Amazon who searched for what. However, it is just as bad for Canonical to collect your personal information as it would have been for Amazon to collect it."


Google defines Spyware as a software that enables a user to obtain information about another's computer activities by transmitting data covertly from their hard drive.

How to do safe search?

In order to do safe browsing on your dashboard you need to filter result. Doing this you can let your interested machine to search for you. Just unclick the sources which you don't want to get you information. 
Debian has provided an easy method to browse your machine offline. In order to do so as shown in the picture below Off the on button and you are totally ofline. None of your searched data will be used by the online sources.


Why always to start from the scratch and bang your head on the wall getting stocked on a very tiny simple problem. So I wish some true Linux genius would maintain two specific kind of blog i.e. codelinux and corelinux.


Where Bloggers would describe every minute details about Linux Based OS, every simple idea and information regarding the development of Linux and its stability in various distributions.A blogger could prepare some kind of course / syllabus which would consider specially beginners and experts as well and clearly identify that beginners can accomplish following things and will need to study following materials in order to reach next level.

Learning the theories are only not sufficient to be smart because  learning linux is nothing until you are  not able to perform it( say code / modify / customize it).
And most of the time every action on linux is performed through codes or commands. So  I wish a blog or blogger to describe code and concepts behind how it  works. Experts can easily identify where beginners may have problems in understanding the flow , so they can comment on it and every beginners could easily learn from it.


In case your laptop is never used by anobody else, then I see no use of Guest Session. Guest session is only necessary if you let other people to share your laptop. In my case I never let anyone to use my laptop, hence for me my user account is enough. So I removed the gurst session from my device.In order to remove the guest session, do following things in your terminal:
  • First open your terminal:  CTRL+ALT+T
  • Then type: sudo gedit /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf
  • In your text editor simply add this line of code allow-guest=false
Now save your configuration file, Close it and restart, this is what you will see:

Troubleshoot Network Manager, Apache, Wireless...

Today's Blog is all about networking stuffs and I will be covering following points:
  1. Know your Network Controller Device with lspci
  2. Display all interfaces which are currently available, even if down with ifconfig
  3. Enable the service networking 
  4. Enable Apache server
  5. Then Enable Network Manager with network-manager
  6. Then  Enable your WiFi with nmcli nm


Then we are all set to run the internet.And now we are some basic troubleshooter about networking, though networking is a huge this would be the first step. Not actually first first step in networking is always theory The Basics of Networking, but we are not dealing with it today. So lets begin

1. In order to know  the hardware devices assembled in your laptop open your TERMINAL CTRL+ALT+T and then type lspci .
This displays all the hardware devices  like PCI BRIDGE, SATA controller, SMBus, USB Controller, Audio Device assembled in your laptop / computer. 

My Network controller is:
02:00.0 Network controller: Broadcom Corporation BCM4313 802.11bgn Wireless Network Adapter (rev 01)

2. So now we need to know the interfaces that are available in our UBUNTU.  To see this type ifconfig in the terminal and you will see the output like this :

3. To access the internet first your hardware device should be activated, In order to do so type 
sudo service networking  and press tab twice which displays  arguments like:
 force-reload       reload        restart       start         stop
Perform any you need.

4.  To enable apache server in terminal type:

      sudo service apache2 start

5.  Now enable the network manager. In order to do so in terminal type:
     sudo service network-manager start 

6. Now First view the available connecting points Wireless point or Ethernet. To view the available wifi points in terminal type
     sudo nmcli con list

This displays the available devices With its UID and SSID.
Now to enable the wifi in terminal type:

      Sudo nmcli con up SSID or the UID

You can manipulate these basic networking commands and  triubleshoot on your own.


Can you Set a picture of yours as default Ubuntu Desktop Wallpaper?

Well, setting a picture of yours as a wallpaper is totally different then setting default images as wallpaper.That picture of yours after it is deleted or moved in another location, your wallpaper either gets blank or some default images are set as wallpaper.

So in order to set your image as default image you should  work on following steps:
I have tried this tweak  on both 12.04 LTS and 14.04LTS and it works absolutely fine.
  1. First copy your image to /usr/share/backgrounds/ Do this from terminal using root prompt or do it from Nautilus  typing nautilus in terminal, so that you will not face permission denial.
  2. Edit  the XML file /usr/share/backgrounds/contents/trusty.xml and paste this code:
Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format which is both human-readable and machine-readable. It is defined by the W3C's XML 1.0 Specification[2] and by several other related specifications,[3] all of which are free open standards.[4]  (Definition referenced from Wkipedia)


Instead of Aurora_500PX.jpg keep your filename.

     3. Edit file /usr/share/gnome-background-properties/trusty-wallpapers.xml

    <name>AURORA 500PX</name>

Edit your filename instead of Aurora_500PX.jpg

Default Ubuntu Wallpapers

Look there are fourteen default wallpapers in Ubuntu. Our purpose is to set our image in that list so that next time we won't have any problem even we lose the picture or move it to another location. 

You can see the image selected with red rectangle and its thumbnail inside the monitor on your left which is the AURORA Borealis  downloaded from 500PX.com
And you can even see I have messed up with images duplication.

Troubleshoot your dead screen in Ubuntu with LightDM.

Troubleshoot your dead screen in Ubuntu with LightDM.

This works great in times when you lose your user interface and reach a dead end.In order to troubleshoot your black screen you need to go through following steps:

  1. Open a Virtual Console
virtual console (VC) – also known as a virtual terminal (VT) – is a conceptual combination of the keyboard and display for a computer user interface. It is a feature of some operating systems such as BSDLinux, and UnixWare in which the system console of the computer can be used to switch between multiple virtual consoles to access unrelated user interfaces. Virtual consoles date back at least to Xenix in the 1980s. 
The Keyboard Combination to open Virtual Terminal is CTRL + ALT + F1. You can even use F2 to F6, but remember F7 is your recent console.

       2. Run LightDM from terminal

LightDM is an X display manager that aims to be lightweight, fast, extensible and multidesktop. It uses various front-ends to draw login interfaces, so-called Greeters. 

I understand that lightdm is the display manager like explorer.exe manages window's display. So a dead screen appears means your lightdm is off.Run it typing: 
sudo lightdm start in your terminal and you are into your interface.

NOTE: Definitions are referenced from wikipedia


My 'UBUNTU 14.04' takes too much time after first boot. Well genius people will have many tricks and tweaks to speed up their systems but as a beginner  I am researching in the internet about following things which can possibly boost up performance of Ubuntu:
  1. Packages / Software installed in my #Ubuntu.
  2. Distinguishing useful / obsolete software.
  3. Removing unnecessary software, Releasing space, which can increase the speed.
This could be one way of solving the problem of slow performance of speed.

Today I will show  some ways to see the packages  and software installed in Ubuntu.

  1. Synaptic Package Manager

To open the Synaptic Package Manager in terminal type:

[email protected]:~$ sudo synaptic

This will open the GUI of Synaptic Manager. From there you can explore the installed packages.

    2. dpkg --get-selections

To get a list of packages installed locally do this in your terminal:

[email protected]:~$ sudo dpkg --get-selections | grep -v deinstall

To save that list to a text file called packages on your desktop do this in your terminal:

[email protected]:~$ dpkg --get-selections | grep -v deinstall > ~/Desktop/packages

     3.  aptitute

To get just the packages which were expressly installed (not just installed as dependencies), you can run

[email protected]:~$ aptitude search '~i!~M'

This will also include a brief description, which you may want. If not, use the option -F '%p'

     4. Create Backup

Create a backup of what packages are currently installed:

[email protected]:~$ dpkg --get-selections > list.txt

Then (on another system) restore installations from that list:

[email protected]:~$ dpkg --clear-selections

[email protected]:~$ sudo dpkg --set-selections < list.txt

To get rid of stale packages

[email protected]:~$ sudo apt-get autoremove

To get installed like at backup time (i.e. to install packages set by dpkg --set-selections)

[email protected]:~$ sudo apt-get dselect-upgrade

There are many documentations available in the internet and I searched only few intelligent peoples'  brain. There are many users out there with creative ideas to manipulate terminals and  bash scripts. it can by you as well.

So now I know to list out all the packages and save them in txt file. Next time I will show some methods to remove the old and obsolete packages. In a few blogs we will be able to maintain the speed of our OS i.e. UBUNTU

See you guys soon.