Linux

🚀 Introduction If you’re managing a Linux server, you’ll quickly come across the systemctl command. It allows you to control services (programs running in the background like Nginx, SSH, MySQL, etc.) and manage their automatic startup. For beginners, this command might seem intimidating at first. Don’t worry — we’ll go over everything step by step, from the basics to more advanced usage. 🔧 What is a service? A service in Linux is a program that runs in the background (called a daemon). Examples of services: ...

🌐 Introduction: What is a Web Server and Why Use Nginx? When you type an address in your browser (like example.com), your browser sends an HTTP request to a server. The web server is the program that receives this request and sends back a response—usually an HTML page. Nginx is a fast and lightweight web server, capable of handling a large number of concurrent connections. It is often used for: ...

🔍 Why use htop? When your server slows down or you want to monitor the system activity in real-time, htop is a simple, effective, and visual tool. It’s a modern alternative to the top command. With htop, you can: View CPU, memory, and swap usage Identify resource-intensive processes Sort, filter, and kill processes easily Use a colorful, interactive, and clear interface 🛠️ Installing htop ➤ On Debian / Ubuntu: sudo apt update sudo apt install htop ➤ On CentOS / RHEL / Fedora: sudo dnf install htop # or 'yum install htop' on CentOS 7 👁️‍🗨️ Understanding the htop interface Simply run: ...

Why use an SSH key? When connecting to a Linux server, we often use SSH (Secure Shell). By default, SSH allows login with a password — but this is not secure. The best practice is to use an SSH key, a kind of digital password that is much harder to guess or break. 1. Generate an SSH key pair On your local computer, open a terminal and run: ssh-keygen -t rsa -b 4096 -C "your.email@example.com" Explanation: ...

Objective of this article: You have two Linux machines (or a local computer and a remote server), and you want to transfer files between them over the network, securely. We’ll see three classic tools: scp, rsync, and sftp. 📦 Why transfer files over SSH? SSH (Secure Shell) is not just for remote terminal access. It can also be used to transfer files securely. Unlike FTP or HTTP, all data is encrypted end-to-end. ...

Goal of this article: You’ve just installed a Linux server for the first time (on a VPS or physical machine) and don’t know where to start to secure it? This guide is for you. I’ll walk you through 5 essential steps to protect your server right after installation. 🛑 1. Create a non-root user with sudo On Linux, the root user has full control over the system. But logging in directly as root is dangerous: a single typo can break your system, and it’s also a top target for attackers. ...

🖥️ The Unsung Role of the Systems Administrator A Silent but Vital Presence The systems administrator ensures IT infrastructure runs smoothly, securely, and reliably. While their work often goes unnoticed when done right, it’s foundational — without them, services go down, backups fail, and security crumbles. A Continuously Evolving Role Once limited to managing physical servers and tape backups, today’s sysadmin operates in hybrid, cloud-native environments. From Linux shells to AWS, and from virtualization to Kubernetes orchestration, the job has become deeply multifaceted — demanding both breadth and depth. ...