Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Articles by Satish Kumar
Page 24 of 94
How to Delete Old Unused Kernels in CentOS, RHEL and Fedora?
Kernel management is a crucial system administration task in CentOS, RHEL, and Fedora. When you install kernel updates, the old versions are kept as a safety measure, but over time these can accumulate and consume valuable disk space, potentially causing boot issues or system slowdowns. Removing old unused kernels frees up disk space, reduces boot menu clutter, and eliminates potential security vulnerabilities in outdated kernel versions. However, it's important to always keep at least one or two recent kernels as backup in case the current kernel encounters issues. Checking the Current Kernel Version Before removing any kernels, ...
Read MoreWhy Should We Disable Root-login over SSH on Linux
Root-login over SSH is a common method for gaining access to a Linux server, but it poses significant security risks. In this article, we will explore the reasons why disabling root-login over SSH is a critical security practice, and provide step-by-step examples of how to implement this safeguard. What is Root-Login Over SSH? When a Linux server is set up, the root user is created by default. The root user is the most powerful user on the system, with unrestricted privileges to perform any task, including making changes to system configuration, installing software, creating users, and accessing all ...
Read MoreHow to create multiple level subdomains with apache2 and or PHP
Subdomains are a powerful way to organize your website into distinct sections, making navigation easier for visitors. Creating multiple level subdomains like blog.example.com or shop.blog.example.com can be accomplished efficiently using Apache2 web server configuration and PHP scripting. This approach allows for flexible website architecture and improved content organization. What are Subdomains? Subdomains create separate sections of your website with unique URLs. Instead of placing all content on www.example.com, you can create dedicated areas like blog.example.com for articles or shop.example.com for e-commerce. This structure improves user experience, simplifies content management, and can enhance SEO by creating focused content areas. ...
Read More10 Examples of How to Use New Advanced Package Tool (APT) in Ubuntu/Debian
Advanced Package Tool (APT) is the default package management system for Ubuntu and Debian Linux distributions. It provides a powerful command-line interface for installing, updating, removing, and managing software packages. APT simplifies software management by automatically handling dependencies and maintaining package integrity. Updating the Package Cache Before installing or updating packages, it's essential to refresh the package cache. The package cache contains information about all available software packages in the configured repositories. sudo apt update This command downloads the latest package information from all configured repositories and updates the local package database. Installing ...
Read MoreHow to Clean a Linux Zombie Process
A Linux zombie process is a process that has completed execution, but its parent process has not yet collected its exit status. These processes remain in the system's process table consuming minimal resources but can accumulate over time. Understanding how to identify, handle, and prevent zombie processes is essential for maintaining system health. Zombie processes occur when a child process finishes but the parent hasn't called wait() or waitpid() to read the child's exit status. The process becomes a "zombie" − neither fully alive nor completely dead. What Are Zombie Processes When a process terminates, it doesn't ...
Read MoreMulti Pointer X (MPX) support
Multi Pointer X (MPX) support is a feature of the X Window System that enables multiple users to interact with a single computer simultaneously, each with their own keyboard and mouse. This capability transforms a single workstation into a collaborative platform where several people can work independently on the same machine, making it valuable for educational environments, design studios, and accessibility applications. What is Multi Pointer X (MPX) Support? The X Window System is a foundational windowing system used on Unix-like operating systems such as Linux and macOS. Traditionally, X servers handle input from a single keyboard and ...
Read MoreHow Do so (Shared Object) Filenames Work in Linux
Shared Objects (SO) are dynamic libraries in Linux that contain code and data shared between multiple processes. Similar to DLLs in Windows, SO files enable efficient memory usage and modular programming by allowing multiple programs to share the same library code loaded in memory. What are Shared Objects? Shared objects are files containing executable code and data that can be loaded and linked at runtime. When a program needs functionality from a shared library, the dynamic linker loads the SO file into memory and makes it available to the requesting process. Multiple programs can simultaneously use the same ...
Read More10 Interesting Linux Command Line Tricks and Tips
The command line interface (CLI) is a powerful feature of Linux operating systems that allows users to execute commands directly through text input. While it may appear intimidating initially, mastering CLI commands can significantly boost productivity and system control. This article covers essential Linux command line tricks and tips to enhance your terminal experience. Navigation Essentials Efficient navigation forms the foundation of command line mastery. These basic commands will help you move through the filesystem with confidence. Directory Navigation Use the cd command to change directories. Here are the most common navigation patterns − ...
Read MoreRedirecting the Output of an Already Running Process on Linux
Redirecting the output of an already running process on Linux is a powerful technique that allows you to capture or reroute the stdout and stderr streams of processes that are currently executing. This capability is essential for system administrators and developers who need to monitor, debug, or analyze process output without interrupting the running application. Using /proc File System for Direct Redirection The most direct method involves manipulating file descriptors through the /proc filesystem. Every running process has file descriptors accessible via /proc/PID/fd/. Redirecting stdout to a File # Find the process ID ps aux ...
Read MoreEasy way of installing Eclipse plugins on Ubuntu
Eclipse is one of the most popular integrated development environments (IDEs) used by software developers worldwide. It offers a comprehensive range of features including code editing, debugging, testing, and deployment. To extend Eclipse's functionality, developers often need to install additional plugins. This guide demonstrates the straightforward process of installing Eclipse plugins on Ubuntu using the built-in Eclipse Marketplace. Prerequisites Before installing Eclipse plugins, ensure that Eclipse is already installed on your Ubuntu system. If Eclipse is not installed, download it from the official Eclipse website. Once Eclipse is ready, you can proceed with the plugin installation steps below. ...
Read More