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GUI notifications from shell scripts in Linux allow you to display visual alerts and messages to users. Two primary tools accomplish this: notify-send for desktop notifications and zenity for interactive dialog boxes. Using the notify-send Command The notify-send command is part of the libnotify library and comes pre-installed on most Linux distributions. It displays brief desktop notifications that appear in the system notification area. Basic Syntax notify-send [options] Simple example displaying a notification − notify-send "Hello" "World" Common Options Option Description Example Values ... Read More
As demand for web hosting services grows, hosting providers are continually looking for ways to automate their billing processes. Commercial billing platforms offer a comprehensive solution, but not every provider has the budget for expensive proprietary software. Fortunately, open source billing platforms provide a cost-effective alternative to automate billing, client management, and payment processing. In this article, we will explore eight open source commercial billing platforms specifically designed for hosting providers. Top Open Source Billing Platforms WHMCS WHMCS is one of the most popular billing platforms for hosting providers. It offers complete client management and billing software with ... Read More
Linux is a widely used open-source operating system that offers users the flexibility to execute programs from any location on the system. Unlike other operating systems, Linux does not restrict programs to fixed directories, enabling users to access executables from anywhere. This feature is particularly advantageous when you need a program to run from multiple locations or when managing custom software installations. To execute programs from anywhere in Linux, the system uses the PATH environment variable, which contains a list of directories where Linux searches for executable files. Understanding how this works and where programs are typically stored is ... Read More
Virtual Private Network (VPN) technology is essential for secure remote access to networks and resources. OpenVPN Access Server is a popular VPN solution that provides a scalable and robust VPN infrastructure for enterprises and organizations of all sizes. In this tutorial, we will walk through the complete process of installing and configuring OpenVPN Access Server on Ubuntu 20.04. Prerequisites Before we start, ensure you have the following prerequisites − A VPS or dedicated server with Ubuntu 20.04 installed Root access to the server A domain name pointing to your server IP address A static IP address ... Read More
A Layered Operating System is an architectural approach where the operating system is divided into multiple hierarchical layers, each with specific functionalities. This design was developed as an improvement over early monolithic systems, providing better organization, maintainability, and modularity. Why Layering in Operating System? Layering provides distinct advantages in operating system design. Each layer can be defined separately and interact with adjacent layers as required. This approach makes it easier to create, maintain, and update the system since changes in one layer specification do not affect other layers. The layered structure also enhances debugging and testing capabilities, as ... Read More
Postfix is an open-source mail transfer agent (MTA) that allows users to send and receive email on Linux systems. It is an efficient and easy-to-use solution that can be configured to work with various email providers, including Gmail. In this article, we will show you the steps to configure Postfix using Gmail SMTP on Ubuntu. This process involves setting up your Gmail account to allow apps to access it, installing and configuring Postfix, and testing the setup to ensure it works correctly. Why Use Gmail SMTP with Postfix? Using Gmail SMTP with Postfix offers several benefits: ... Read More
Running a Java application as a service on Linux allows your application to start automatically at boot time, run in the background, and be managed using standard system commands. This approach ensures your Java applications remain running even after terminal sessions are closed and can be controlled through the system service manager. Understanding Linux Services A service (or daemon) in Linux is a background process that performs specific functions without direct user interaction. Services can be started automatically at boot time and controlled using command-line tools or system service managers like systemd or Upstart. To create a ... Read More
If you're a Linux user who often downloads files from the web, you might be familiar with slow download speeds that come with it. Fortunately, there's a tool called Axel that can help you accelerate your file downloads from command line. In this article, we'll discuss what Axel is, how it works, and how you can use it to speed up your downloads. What is Axel? Axel is a command-line tool that is used to accelerate file downloads in Linux. It is a lightweight and fast download accelerator that splits a single file into multiple parts and downloads ... Read More
When it comes to web applications and services, reverse proxy servers are a critical component that helps distribute traffic, improve security, and provide load-balancing capabilities. Open-source reverse proxy servers for Linux are readily available and offer an array of features that can be tailored to meet your specific requirements. In this article, we'll examine 8 top open-source reverse proxy servers for Linux, including their features, advantages, and limitations. NGINX NGINX is one of the most popular open-source reverse proxy servers for Linux. It's lightweight, fast, and offers a range of features such as load balancing, HTTP caching, ... Read More
OpenVPN is a popular open-source VPN protocol that enables secure and private communication over the internet. With OpenVPN, you can create a virtual private network accessible from anywhere, providing encrypted connections for remote users. This tutorial covers installing and configuring OpenVPN server on CentOS 8/7 systems. Prerequisites Before proceeding with the installation, ensure you have the following prerequisites − A CentOS 8/7 server with root access A static public IP address An SSH client installed on your local machine Basic knowledge of Linux command line Step 1 − Install OpenVPN Server First, install ... Read More