Linux provides us a way with which we can create symbolic links or symlinks, that issimply pointing to another file or folder on your machine.Now let's understand what symbolic links actually mean and how to make use of it.Symbolic links in simple terms mean advanced shortcuts. A symbolic link that you create will appear to be the same as the original file or folder which it is pointing to, even though it’s simply a link.For example, let’s say that you have a program that needs to store its files at /home/user/Downloads/.program. But you actually want to store those files on ... Read More

We know that we can make use of the top command to print all the processes that are running in the background. Though the top command is used to print the list of processes or threads that are currently managed by the Linux kernel, it is still not a convenient way to check if a particular service is running in the background or not.In order to understand how to check whether a particular service is running or not, we first must understand what a service actually means in Linux. A service is basically a process or group of processes that ... Read More

Use the plot method of matplotlib and set the legend with different sets of colors.StepsSet the X-axis label using plt.xlabel() method.Set the Y-axis label using plt.ylabel() method.Plot the lines using plt.plot() method with [9, 5], [2, 5] and [4, 7, 8] array.Initialize two variables; location = 0 for the best location and border_drawn_flag = True (True, if border to be drawn for legend. False, if border is not drawn).Use plt.legend() method for the legend and set the location and border_drawn_flag accordingly to get the perfect legend in the diagram.Show the figure using plt.show() method.Exampleimport matplotlib.pyplot as plt plt.ylabel("Y-axis ") ... Read More

Tmux is a terminal multiple for Unix OS. It provides multiple terminal sessions to its users. It is used when we are using cloud-based services (like Azure, AWS) for the creation of separate terminals for different remote users.While working with web services, one needs to create an EC2 instance on the webserver provided by the company to work on it by creating a session.Now, let’s see the steps of working on a UNIX (Ubuntu) webserver.Step 1 − Write/copy the IP address of your AWS console and download the key file from the console. You will get these from your vendor ... Read More

The Linux GUI based terminal window has many colours and font settings which can be enhanced as per the user choice. All these can be done using the shell commands and not just by clicking mouse buttons in the GUI component settings.Most of these settings are handled through variables whose value can be changed or assigned by commands. In this article we will see how to handle the terminal prompt settings in Ubuntu based systems.The PS1 VariableIt is a environment variable which controls the primary prompt string which is displayed when the shell is ready to read a command. There ... Read More

Are you new to Linux/Ubuntu? Do you know, which version of Ubuntu/Linux is currently installed on your machine? If you are in a dilemma, then this article explains you about how to find out Linux version currently installed on your machine.Method 1Use the following command to find Ubuntu version as shown below −$cat /etc/*-releaseThe sample output should be like this –DISTRIB_ID=Ubuntu DISTRIB_RELEASE=16.04 DISTRIB_CODENAME=xenial DISTRIB_DESCRIPTION="Ubuntu 16.04.1 LTS" NAME="Ubuntu" VERSION="16.04.1 LTS (Xenial Xerus)" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 16.04.1 LTS" VERSION_ID="16.04" HOME_URL="http://www.ubuntu.com/" SUPPORT_URL="http://help.ubuntu.com/" BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/" UBUNTU_CODENAME=xenialTo get the kernel information about Linux machine, use the following command as shown below −$ hostnamectlSample output should be ... Read More

In this article, we will learn how to increase the swap space, which will solve the memory errors in applications. This will cover how to add a swap file to an Ubuntu Linux.Anyway, this is recommended to utilize the spinning hard disk drivers for swap as SSD can cause issues with hardware degradation over time. Due to this reason, do not enable swap on Cloud where the SSD storage is provided.What is Swap file?The Swap is a place where the OS can store temporary data as it can no longer holds in RAM. Basically, this will increase the ability of ... Read More

In this article, we will learn about how to fix the Dirty Cow Linux Vulnerability. The Dirty Cow Linux Vulnerability was escalated on Oct 19 2016 as it is a privilege escalation vulnerability in the Linux OS on kernel level which was disclosed with the name as Dirty COW as it will create a condition that kernel handles COW (Copy-on-Write), which exists for a long time since 2007 from kernel version 2.6.22 as most of the servers are at risk.Dirty Cow means that a regular or an unprivileged user on the server will gain write access to all the files ... Read More

In this article, we will learn how to secure Mongo DB on Ubuntu 16.04. In previous versions the Mongo DB is vulnerable to automated exploits because, by default, there is no authentication which was allowed to interact with the database, any user can create, read, modify and destroy the database and the contents, this is because of the Mongo DB daemon which can listen to all interfaces as default settings.Enabling Authentication and Adding Admin UserThis issue has been mitigated in the latest versions of Mongo DB after version 3.x releases, however, the authentication is still disabled as default settings, so ... Read More

Sysdig is an open source application, It captures system state and activity from a running Linux instance, then saves, filters and analyzes. It is scriptable in Lua and consists of a command line interface and an effective interactive UI, Sysdig is a combination of strace + tcpdump + htop + iftop + lsof + transaction tracing + awesome sauce. This article explains about -“How To Monitor Your Ubuntu System with Sysdig”.Installing SysdigConfigure the apt repository with trusted Draios GPG key as shown below –# curl -s https://s3.amazonaws.com/download.draios.com/DRAIOS-GPG-KEY.public | apt-key add - # curl -s -o /etc/apt/sources.list.d/draios.list http://download.draios.com/stable/deb/draios.listTo update the package ... Read More