Author: Rahul

The shebang, also known as a “hashbang” or “sharpbang”, is an essential part of Bash scripts and other executable scripts in Unix-based systems. This seemingly simple line of code tells the operating system how to interpret and execute the script. In this article, we will explore the history and purpose of shebangs, common Bash shebangs and their meanings, how shebangs affect script portability, differences between shebangs in various Linux distributions, and tips for ensuring your Bash script runs as expected with the appropriate shebang. History and Purpose of Shebangs The shebang was introduced in Unix systems in the late 1970s…

Remote access to servers and other devices is a critical task for many professionals, including system administrators, developers, and IT technicians. SSH (Secure Shell) is a popular protocol used to connect to remote devices securely, and SSH clients are used to establish these connections. However, the command-line interface used by most SSH clients can be intimidating and difficult for some users. In this article, we’ll introduce you to some user-friendly SSH clients for Windows that make remote access easy. 1. MobaXterm MobaXterm is a user-friendly SSH client that’s designed for system administrators and power users. MobaXterm includes a tabbed interface,…

Postfix is a popular open-source mail transfer agent (MTA) used to route and deliver email on Linux systems. It provides a robust and efficient means of handling mail delivery. In this tutorial, we will show you how to configure Postfix to use Gmail’s SMTP service on Ubuntu and Debian-based systems. This setup allows you to send emails through Gmail’s infrastructure, providing better deliverability and reducing the chances of your emails being marked as spam. Prerequisites Before proceeding, ensure that you have the following: A system running Ubuntu or Debian-based distribution. A Gmail account or Google Workspace account with ‘Less secure…

PHP is a server-side scripting language that is used to develop dynamic web applications. Arrays are an essential part of PHP, and they allow developers to store and manipulate multiple values in a single variable. In this tutorial, we’ll discuss PHP arrays, their types, how to create and manipulate them, and some useful array functions. What is an Array in PHP? An array is a special type of variable that can store multiple values in a single variable. In PHP, arrays can store different types of data, such as integers, strings, and even other arrays. Each value in an array…

Flask is a popular and lightweight Python web framework that enables developers to build web applications with ease. One of the key aspects of deploying a Flask application is choosing the right web server and gateway interface. In this article, we will discuss how to deploy a Flask app using Apache and WSGI (Web Server Gateway Interface) on a Linux-based system. Apache is a powerful and widely-used web server, while WSGI is a standard interface between web servers and Python applications. This comprehensive guide will walk you through the entire process of deploying a Flask app with Apache and WSGI…

OpenSSL is a robust, full-featured open-source toolkit that implements SSL and TLS protocols, as well as a general-purpose cryptography library. It is widely used for managing SSL/TLS certificates, private keys, and Certificate Signing Requests (CSRs) in various systems. In this article, we’ll explore how to work with SSL certificates, private keys, and CSRs using OpenSSL, along with examples to help you understand each step. Introduction SSL Certificates: These digital certificates are used to establish a secure connection between a server and a client using SSL/TLS protocols. They contain information about the certificate holder, the certificate issuer, and the public key.…

Python is a popular programming language with a vast range of applications, including data science, web development, and automation. One of the most basic and essential data structures in Python is the list. A list is a collection of values or items that can be of any data type, including strings, integers, floats, and even other lists. In this article, we will explore how to create and read a list in Python. Creating a List To create a list in Python, we use square brackets [] and separate the items in the list using commas. Here is an example of…

Linux is a popular operating system used by millions of users around the world. One common task when working with Linux is creating and managing directories. In this article, we will cover how to create a directory in Linux only if it does not already exist. This is useful when writing scripts or when performing tasks that require creating multiple directories with unique names. Using the ‘mkdir’ Command with ‘-p’ Option The ‘mkdir’ command is the most basic way to create a directory in Linux. The ‘-p’ option allows you to create a directory only if it does not already…

Bash, the Bourne-Again SHell, is a popular command-line shell and scripting language that is widely used for its simplicity and ease of use. One of the most common tasks that one might need to perform using Bash is looping through the content of a file. In this article, we will explore different methods to loop through a file’s content using Bash scripting, including reading line by line and word by word. Method 1: Using the ‘while’ Loop and ‘read’ Command The ‘while’ loop combined with the ‘read’ command is the most common method to loop through the content of a…

A firewall is a security system that monitors and controls the incoming and outgoing network traffic based on predefined security rules. It is an essential component of any secure network, whether it is a personal computer or a large enterprise network. Uncomplicated Firewall (UFW) is a user-friendly, command-line interface for managing iptables, the Linux kernel’s built-in firewall. Designed to be simple and easy to use, UFW helps administrators manage and enforce network security policies without delving into the complexities of iptables. In this article, we will explore common firewall rules and commands to help you get started with UFW. Installing…