Category Archives: Tips and Tricks

How to setup Google Public DNS on Ubuntu (11.10/12.04)

DNS i.e Domain Name System is a Naming System responsible for translating the human friendly domain names to I.P address. In most of the cases, by default – you would be using your ISP’s DNS server which may be slow or some geographical restrictions might be there. In such cases, it’s often recommended to use DNS service provided by third party such as OpenDNS (refer to article about setting up OpenDNS in Ubuntu, basically the process are same – only the I.P address of the servers are different) or the Google Public DNS, did I forget to mention that both DNS service are Free! (in general). it supports IPv4 as well as IPv6.

So, if you are not sure where to use ISP DNS server or Google Public DNS then you must know about some additional benefits of using Google Public DNS –

  • Faster DNS Lookup
  • Improved Security (Protection from phishing sites/domans)
  • No redirection (additionally, you can also access the sites blocked from ISP DNS Provider)

Change your Internet Settings to use Google Public DNS

Although the tutorial is primarily targeted for Ubuntu users but it should also work well on similar GNU/Linux distributions such as Debian, Linux Mint, OpenSuse etc. Just follow the simple steps and enjoy faster web surfing with Google Public DNS.


#1. Go to Network -> Edit Network Connections


#2. Select your Network connection, you want to setup with Google Public DNS and click Edit. Then go to IPv4 Settings tab and select “Automatic (DHCP) addresses only ” in the Method section.

google public dns

#3. Now, specify the IP address in DNS Servers field and click on SAVE. Then restart your Router to start using Google Public DNS servers.,

Recommended Reading(s) and Reference(s)

10 Applications You Must Try on Ubuntu 11.10/12.04

Ubuntu has now become the most popular GNU/Linux distribution among the desktop users and developers, so now a days you can find almost any application for any kind of task, most of them are free softwares but some are commercial too.

At the time of writing this post – I’m using Ubuntu 11.10 (which is the latest sable release) – so the applications has been tested on 11.10; Ubuntu 12.04 LTS will be out, in next few months, I’ve tried alpha versions and I’m sure these applications would also work well on 12.04 (and earlier versions such as 11.04/10.04 …) or other similar GNU/Linux distro such as Linux Mint, Debian, etc. So I’ve made a top 10 list of some cool Applications that is worth trying!

10 Awesome Free Softwares for Ubuntu

10. Zim


Zim is a cross-platform desktop wiki application that just works. it is well suitable for taking/organizing notes, TODO list, brainstorming thoughts or innovative ideas. You might have used a notes management application such as Evernote or OneNote (which is quite popular) but the simplicity of Zim will make you a fan of it. The notes are stored on the desktop in a plain text format and it’s saved automatically. You can even create new page just by linking to non-existing page.

A lot of cool plugins are available to add some extra cool features to Zim. Go to Edit -> Preferences ->Plugins and enable the plugins you want to use. Some of the most useful plugins are –

  • Spellchecker
  • tags
  • Insert Equation
  • Insert Diagram
  • Insert Screenshot
  • Insert Symbol
  • Tray Icon
  • quick note
  • version control (Bazzar VCS)
  • Link Map (some sort of Mind Map)

Most of the above plugins are really cool! Here is a snapshot of Link Map view (first enable the plugin and go to View -> Link Map View) – representing the structure of my notes.

link-map-view in Zim

In Ubuntu you can install it in one simple command –

sudo apt-get install zim

Other users can get it from official download page.

9. Steadyflow


Steadyflow a simple and easy to use Download Manager based on GTK+. The GUI tends to follow minimal approach, in order to encourage simplicity, it’s pretty clean and straightforward. To begin the download process, enter the URL of the file, then locate the folder where you want to save it, specify a file name (although it will be automatically done by the application – so you can leave the field default if you don’t want any specific file name) then There is one great feature – that can be used to execute commands or trigger another application when the download is complete, by default leave to “Do nothing upon completion” if you don’t want to trigger any action on completion.

Pausing and Resuming download activities is very simple and there is one tray icon in bottom right corner to control the application.


To install Steadyflow Download Manager, execute the command or visit official page (for more detail) –

sudo apt-get install steadyflow

8. Pinta Image Editor


Pinta is a simple and easy to use, beginner friendly image editing/drawing application, very similar to Microsoft Paint program. It is a free software, available for all platforms, the latest stable version is Pinta 1.1 (released few months ago). It has lot of cool features like Drawing Tools/Shapes, Customizable workspace, Unlimited layers, Full History etc, Adjustment and cool effects (e.g Artistic Effects for Oil Painting, Pencil Sketch and Ink Sketch), although it doesn’t have all sophisticated features like GIMP and Adobe Photoshop but still worth useful for quick editing, specially for beginners (probably due to its simplicity and ease of use).

Installing Pinta Image Editor in Ubuntu 11.10/12.04

sudo apt-get install pinta

or Download It (older versions or other GNU/Linux distro)

7. K3b

k3b - Disc Creator

K3b is a CD/DVD burning application for GNU/Linux based distributions. K3b is a feature rich /sophisticated disc creating application – so you can create different kinds of CD/DVD – very easily using K3b.

Important Features of K3b at a Glance

  • Create Audio CD
  • Create Data CD
  • Create Mixed Mode CD
  • Create Video CD
  • CD Copy
  • DVD Burning
  • CD Ripping
  • DVD Ripping
  • Write ISO Image

Full Features List (Official Website)

Install K3b on Ubuntu

sudo apt-get install k3b

6. Pencil

pencil - cartoon creator

Pencil is a Cartoon drawing program. It focuses on simplicity but it has a lot of features – that will allow you to create cool cartoons/hand drawings and animations. Pencil is very easy to use and it is available not only for GNU/Linux but also for Windows and Mac.

Install Pencil in Ubuntu

sudo apt-get install pencil

5. Synapse


Synapse is a semantic launcher that enables you to launch applications or find files/documents quickly using Zeitgeist Engine (a service that logs user activity and events, so it helps Synapse in searching stuffs semantically). Simply – start the application and kick start the apps or files you are looking for, and – it seems better than Unity’s Lens. If you haven’t tried any quick App launcher yet, then you must give it a try – as it may help you in boosting your overall productivity by cutting down the time you usually spends on searching files or starting applications.

Install Synapse in Ubuntu

sudo apt-get install synapse

Now, just hit Ctrl+Space and Enjoy! (or you can launch (Vow!, that’s a Meta Launch :)) Synapse from Applications -> Accessories -> Synapse). Some plugins are also available – which can even help you in finding and executing terminal commands, take a look at the preferences section for more options.

4. Mount Manager


Mount Manager is a simple and easy to use Disk/Partition management software for Ubuntu users. You can Mount/Unmount partitions, edit settings/mount point, change /etc/fstab (which contains FileSystems details and used by many programs including GRUB bootloader, for more info look at man page). It is a robust, stable and easy to use, and of course it is a beginner friendly because on top right you can also read documentation about the options/things you are customizing.

To install Mount Manager in Ubuntu, just execute the command –

sudo apt-get install mountmanager

3. Clementine

Clementine Media Player on Ubuntu

Clementine is a sophisticated Music Player and Organizer, inspired from Amarok 1.4. The Application focuses on speed and easy search/play of your music files/albums. It has a lot of cool features including Smart/Dynamic playlists, tabbed playlists with various import/export options, tag editing, visualizations, supports Ogg, mp3, Vorbis, FLAC, AAC etc, queue manager, desktop notifications, go to official site for more details about the features. It is a cross-platform application, in Ubuntu you can find it in Software Center. It integrates seamlessly with Grooveshark,, Spotify and others.

Install Clementine Music Player in Ubuntu 11.10/12.04

Open a terminal (Ctrl+Alt+t) and execute –

sudo apt-get install clementine

2. digiKam


digiKam is an advanced digital photo management application. it’s a cross platform Application that allows you to manage/organize collections of photo effectively, in a professional way. It is a cross-platform application. It has simple and easy to use interface.

digiKam will allow you to import pictures, organize, view, edit and share it in various ways. Check out the official site for Full List of Features and user guide/manual.

In Ubuntu 11.10/12.04 you can install digikam from terminal –

sudo apt-get install digikam

1. Miro


Miro is a Music and Video player, and you can play not only your local music files but also the internet TV, YouTube etc. Besides that, there is also an option to download the file if you want – so basically miro is a great application that will allow you to play all kinds of stuffs – from one place, it’s kind of ‘All in One’ Entertainment box. The user interface looks cool! and the application is available for all platforms.

Install Miro Music/Video Player / Downloader in Ubuntu 11.10/12.04

sudo apt-get install miro
access blocked website

How to Access blocked websites on Ubuntu

Earlier, I wrote an article about – how to block a website on Ubuntu and now I feel that I should also share some tips about unblocking a website on Ubuntu (or other GNU/Linux based operating system such as Linux Mint), just for the sake of free speech and liberty. It will also help you in bypassing Internet censorship etc if there are any, based on your geographical location.

Although the post has been written for Ubuntu users but some the tips may work well on other operating system too. I’ve tested these techniques on Ubuntu 10.04/12.04 LTS (Long Term Support) but it should work well with older and newer versions such as 14.04 LTS.

access blocked website

4 ways to unblock websites in Ubuntu

1. Using OpenDNS or Google DNS

OpenDNS can also be used in blocking a website but it is good for unblocking a website if your ISP is blocking access to your favorite sites. OpenDNS servers are far better DNS servers than your ISP DNS servers. They provide 100% uptime with extra security, so it will also boost your web surfing pleasure. But in some cases the latency may be high as compared to your ISP DNS server, so first test it well before completely switching to it.

Setup Open DNS in Ubuntu 12.04/14.04
Go to Network settings – > Configure -> IPv4 Settings -> Automatic DHCP Address Only and enter these IP address in Name servers field, separated by comma.,

[ More detailed instruction about opendns set up on Ubuntu ]

Google DNS IP,

2. Using Proxy Server

Proxy surfing is one of the most popular technique to unblock the websites which are blocked in a particular country. The website are banned based on the I.P address so the proxy surfing can easily bypass the IP filtering mechanism as it acts on the behalf of client (eg. Your Computer). There are many ways to use a proxy server – from Network settings (system level proxy) or browser settings (if you want to use proxy server for specific browser) but first you need access to proxy server. There are free proxy servers available that you can use but I won’t recommend that for anything related to sensitive data (e.g your email, password etc). Most of such free options are not reliable and secure enough in most cases.

Update! ZenMate is offering quite reliable service for free and you can install their extension (available for Chrome, Firefox etc). Check out ZenMate to find out more.


Tor is a free software and open network, the best way to access the Internet using virtual tunnel and thus form an anonymous network that will allow you to surf anonymously over the web – without any restriction. The Tor program isn’t only good for unblocking sites but also for privacy and security reasons, it will also prevent you from Internet Surveillance commonly i.e traffic analysis. It is available for all major platform.

Download Tor (If you’re not sure then go with bundled option)

3. By Editing Hosts File

This method is very simple and works if the site is blocked by counter method or if you know the IP address of the website (you want to unblock). Simply open /etc/hosts file and remove the entry for your favorite websites and flush the DNS cache to propagate the changes.

gksu gedit /etc/hosts

In other case if you know the IP address of target website, which blocked using some other mechanism such as ISP level or something else then add an entry (/etc/hosts) for that website along with the correct IP address. The second method seems to be logically correct – if a domain name is resolved at host level then the lookup process is terminated, so host level dns entry should bypass other DNS filtering e.g at ISP level. Therefore it is expected to work (but I have not tested yet, I’ll let you know if it works), give it a try it may work. But it may not work if the website’s IP address changes frequently – because in that case it would be difficult to update the etc/hosts file manually to reflect the new value of IP address.

Adding a DNS entry in etc/hosts file –


Then execute the following command – (to flush DNS cache)

sudo apt-get install nscd
sudo /etc/init.d/nscd restart

4. Use VPN

If you want to explore web without any restrictions then using VPN would be more easier and simple way to achieve that. Your Internet speed should be decent, plus you should be willing to spend some money on a decent VPN service.

I would recommend Private Internet Access, as I’m using this and I’m pretty happy with the service. It’s one of the most trusted VPN provider, they respect user’s privacy more than anyone else. (they’re anonymous VPN provider and they don’t log any connection)

Signup For Private Internet Access (costs $39.95 per Year or you can choose monthly plan if you wish)

If you need any help in setting up private internet access on Ubuntu, you should read this article on setting up VPN in Ubuntu.

Update! – Added 4th point (VPN section) above.
Image Credit : binsurf 
Reference(s) and Recommended Reading(s)


Batch png Optimizer for Ubuntu/Linux

PNG (Portable Network Graphics) is one of the most popular image format used over the web – most of the graphics designers uses png format for designing logo of a website or in computer artwork (because PNG is more suitable for computer generated images). Optimizing image is a good practice in modern web development/work because it will allow the pages to load much faster due to reduced image size. Google also recommends all web masters to use optimized images for faster loading of pages and you may already know that SPEED is one of the most important thing to consider while designing a website or a web application.

Now, you understand the importance of optimize image – but there should be a balance between the quality and the size of an image. Loss-less compression is what most people prefer while compressing/optimizing an image. On Linux based operating systems such as Ubuntu, Linux Mint, Fedora, OpenSuse, PCLinuxOS etc you can also use GIMP with save for web plugin to optimize png images (it also supports other popular image formats such as JPG, GIF etc).

GIMP (with image optimizer plugin) is good when you have few image but what you will do if you want to optimize hundreds of png files because because it doesn’t support batch optimization. That’s where the OptiPNG comes in, a great tool to optimize PNG image.


OptiPNG : Advanced PNG optimizer

OptiPNG is a an open source and cross-platform image compression/optimization tool. It supports batch processing i.e you can optimize bulk of png files in one simple command. It is very powerful application, as it provides you a lot of options such as compression level (1-7) where 1 is minimum and 7 is the maximum compression level. Page Speed (by Google Inc) – one of the most popular website optimization plugin/tool, uses OptiPNG for optimizing png files.

How to install OptiPNG

Ubuntu (11.10/12.04/12.10.. or Linux Mint, it should work with any Debian based distributions) users can install it by executing one simple command from terminal (Ctrl+Alt+t) –

sudo apt-get install optipng

Other user can download it from the official website. Primarily it’s a command line tool but front end for various platforms are also available, pretty useful if you don’t want to get your hands dirty with Terminal.

Optimizing Images using OptiPNG

To optimize image you can just give the file name as argument or specify compression level and other options. Just type optipng at terminal to see the help and options available for this tool.

For single image

optipng file_name.png

it will optimize the image and overrite the existing one, with default speed and compression level.

For Higher Compression (obviously the speed will decrease)

optipng -o7 file_name.png

Optimizing all png images of a directory (at higher compression level 7)

cd path_to_image_directory
optipng -o7 *.png
Editing Hosts file using Nano

how to block a website/domain in Ubuntu

There are lot of softwares available in the market – just to make some websites inaccessible from a computer, possibly for productivity reasons e.g blocking facebook, (facebook is killing productivity ? but I don’t think it’s good way, as I promote free speech, free information and of course, freedom!) or to filter out the sites having contents, which may not be suitable for some users (e.g if you want to block porn sites, to make it inaccessible for kids) or simply to block useless spam sites. Anyway, in this post, you will learn – how to block websites or domains in just a couple of click, without any third party softwares – in an efficient way.

Blocking a website or domain name on Ubuntu

Although, I’m using Ubuntu 11.10, but it should work fine with older (11.04/10.10/10.04..) or newer versions(12.04/12.10..) of Ubuntu, not only on Ubuntu but also on other Linux distributions such as Linux Mint, Fedora, OpenSuse, PCLinuxOS, etc. Just follow the simple steps –

Editing Hosts file using Nano

step #1 : Open a terminal (Ctrl+Alt+t) and execute the following command –

sudo gedit /etc/hosts


sudo nano /etc/hosts

if you prefer command line text editor and it’s more convenient to use in this case.

step #2 : Then add the following line to the file and click on Save (or Ctrl+s) or Ctrl+x, followed by ‘y‘ if you’re using nano text editor (one of the most popular command line text editor, like vim)     

where is a sample domain name which you want to block.

step #3 : That’s all, you’re done! Now open a browser and type the domain name (website address) you specified in above step – => Then you will get an error page such as the it couldn’t be connected to the server or the default server page of your local server (if you’ve installed apache2).

If the domain name is still not blocked then try to flush DNS cache using the nscd (Name Service Cache Daemon).

sudo apt-get install nscd
sudo /etc/init.d/nscd restart

That’s All :)

NOTE : The file system directories shouldn’t be writable for the users for which you have blocked the sites, because in that case they can easily revert the changes, so they shouldn’t be in sudoers or super user groups (add those users in somewhat less powerful group).