User account creation is one of the rare aspects of Linux administration where using text (command line) mode really isn’t any more challenging than using the usual graphical user interface tool. It goes without saying that it is an approachable step for a Linux newbie, and can go a long way in getting an idea about how to proceed in a command line environment.

The most obvious way to go about creating a user account is to use the useradd utility. Adduser is an alternative, which works exactly the same way as useradd (though it may or may not be present in all systems). For all practical purposes, they can be considered to be one and the same.

The Linux environment provides a number of protocols that are intended to create and administer networks, both simple and complex. Networks are the foundations of modern communications, and Linux-based networks account for quite a number of them.

TCP/IP is a layered network protocol first developed by the US Department of Defense for providing a communications bridge between computers of different makes. The protocol essentially aimed to keep the software and hardware portions of networking away from each other so as to avoid any potential conflicts. TCP/IP’s complete focus on interoperability and bridging has made it extremely popular for its focus on usability as opposed to semantics. This protocol is completely integrated into the Linux kernel, and is extremely popular due to its efficiency.

Linux is an operating system with a very wide range of variants. In the Linux environment, they are called distributions, or ‘distros’ in short. Often enough, the abundance of choice can be as much of a hindrance as a lack of it. This makes it boil down to evaluating yourself for what kind of user you are, your general needs, any specific issues and ease at working in a certain kind of environment. This is what makes choosing a Linux distro an important part of a foray into the Linux environment.

Free software, or, to be more specific, Linux, has not been as widespread and popular in enterprises as people had expected years back. This has always seemed like an anomaly to the public in general, and only served to further the myth that Linux is not meant to be used by anyone except pure techies. The proponents and supporters of proprietary software operating systems like Microsoft would like you to believe that Linux is very threadbare on actual features. The insinuation is that Linux is at the very bottom of the user-friendliness and convenience scale, and is simply a waste of time in the constraints of corporate life, such as deadlines.

A privileged program in Linux is one that has special access permissions (privileges) to use files or devices that are usually restricted. This can be done by either using the user ID of a privileged user (root based daemons fall into this category), or by a set user-ID-root (which gives the privileged program another identity effectively).

Privileged programs are a potential risk due to their use of restricted resources, and efforts need to be made to mitigate any potential misuse by someone with malicious intent.

A set-user-ID program can be made to only hold special privileges when it explicitly needs them. If the need for the privileges is only temporary, the program should be made to lose the privileges forever after its explicit purpose is served. For instance, if you want the program to drop its special privileges, add a line of code akin to:

Linux is not really the OS of choice for just absolutely nerdy coders. It has a number of hidden features that will get a chuckle or two out of you at the very least, and give you a great way to kill some time too! These hidden features are called Easter eggs, and Linux has a rather funny assortment of them!

1. An alien goat game!

To be exact, it is a game of GEGLs. In case you have absolutely no idea about what that stands for, it expands to ‘Genetically Engineered Goat, Large’. This hidden game in GNOME is called ‘Killer GEGLs from Outer Space’ and has creatures that resemble goats, only with an extra, alien looking paw by their side. All you need to do to start this game is to hit Alt+F2 on your keyboard, and type ‘gegls from outer space’ in the window that comes up. Have fun!

We all sometimes delete important files accidently. And sometimes we delete a few files thinking that they aren’t important, but later we might realize that we need them. It is best to keep a backup of files so that they can be easily recovered when they are required later. But even if you didn’t keep a backup, it is still possible to regain the deleted files in your Linux system. Let’s see how:

1. Find the partition in which the deleted file was stored. To do this, you can use the pwd command (print working directory) at the shell console.

A UNIX based system like Linux can have multiple file systems. These file systems can in turn have a number of groups, which in turn contain blocks of data and ‘inodes’. Each file system has a descriptor block, which is somewhat like the metadata attached to media files. An inode gives each file a specific identifier in the file system it is in. Each file can extend beyond just a single block of data, depending on its complexity and size.

Inodes

It is a data structure which contains data about a particular file. The ls command followed by –i will tell you about the inode of a file. The inode contains information about the location of the data blocks which contain the particular file you are interested in. It also tells you about the permissions granted to the user for a file, and its physical location.

Today while trying to install Gnome-RDP & after adding the universe repository to my list of repositories I kept getting the following error:

W:Failed to fetch gzip:/var/lib/apt/lists/partial/ae.archive.ubuntu.com_ubuntu_dists_natty_universe_binary-amd64_Packages Hash Sum mismatch, E:Some index files failed to download. They have been ignored, or old ones used instead.

As I am sure I would not be the only one having this error, I have decided to share the resolution path I have took to fix this error.

First step I went to the Ubuntu Software Center => Edit => Software Sources     where I found my  Download from is United Arab Emirates just change it back to Main Servers as shown in the screen shot below:

I have been using Ubuntu 64-bit for about 2 years now, & during that I had came across many 32-bit packages that I wanted to run them where no 64-bit version is provided of the same application. Though when ever I tried to install a 32-bit package on my 64-bit Ubuntu, I was always treated with the following error message:

‘package architecture (i386) does not match system (amd64)’

Many times I was able to avoid the above error by using the following command to install the desired package:

sudo dpkg -i –force-architecture pkgname_i386.deb

–force-architecture <== will tell Ubuntu to allow the installation of 32-bit package on the 64-bit version of Ubuntu.