Category Archives: Linux

29 September, 2026

The vi Cheat Sheet (2026 Edition): From Survival Keys to Power Moves

Use this vi cheat sheet to master survival keys and power moves. Learn vi modes, operator grammar, and vim extensions for fast config editing.

29 September, 2026

Linux Permissions Deep Dive: rwx, Octal, Special Bits, ACLs, and Capabilities

Master Linux permissions with this deep dive. Configure rwx, octal modes, POSIX ACLs, and capabilities to harden shared directories and stop permission denied errors.

29 September, 2026

Linux User and Group Management and Permissions: The Practitioner’s Guide

Master Linux user and group management with precise commands for sudo, permissions, and ACLs. Build secure identities and audit access control for your servers.

29 September, 2026

grep vs. egrep vs. fgrep: One Engine, Three Personalities

Learn the difference between grep, egrep, and fgrep. Fix legacy scripts, handle deprecation warnings, and choose the right mode for fast log analysis.

27 September, 2026

ITsecur Firewall for Webmin: A Point-and-Click IPTables GUI

Install the ITsecur Firewall Webmin module on Rocky Linux 9. Replace firewalld with iptables, configure NAT, and manage stateful rules via a point-and-click GUI.

21 September, 2026

Argus OSINT Framework: Installation and Deployment Guide for Ubuntu Server

Install Argus OSINT on Ubuntu Server using a Python virtual environment. Follow this step-by-step guide to deploy the toolkit for authorized network and web...

14 September, 2026

Deploying Recon-ng on Ubuntu Server: A Step-by-Step Installation Guide

Install Recon-ng on Ubuntu Server 24.04 using a Python virtual environment. Configure API keys, populate marketplace modules, and run your first OSINT scan securely.

5 September, 2026

Linux Partition Types Explained: What they do, checking size, consistency and health

Linux partition types explained: learn what /var, /boot, and swap do. Get the exact commands to check disk size, filesystem consistency, and drive health.

1 September, 2026

Deploying OpenSpeedTest on Ubuntu 24.04 LTS for Internal Network Speed Testing

Deploy OpenSpeedTest on Ubuntu 24.04 using Docker. Configure static IPs, UFW firewall rules, and TLS for a secure internal network speed test server.

24 August, 2026

ipcalc Deep Dive: Mastering Subnet Math Across Every Linux Implementation and Homebrew

Master ipcalc Linux subnetting across Debian, RHEL, and BusyBox. Identify your implementation, handle VLSM splitting, and avoid parsing traps in automation scripts.

1 August, 2026

TCP Flags Deep Dive: Meaning, Behavior, and Troubleshooting

Master TCP flags meaning and troubleshooting. Learn to read raw packet captures, diagnose handshake failures, and correlate wire behavior with FortiGate session states.

24 July, 2026

Deploying FortiClient on Ubuntu Linux: The Complete CLI Reference for Desktop and Headless Endpoints

Deploy FortiClient on Ubuntu via CLI. Install from repo or deb, register to EMS, and configure VPN profiles for headless servers and desktops.

22 July, 2026

Deploying a FortiGate as an IPsec IKEv2 Remote-Access VPN Concentrator for Linux Clients with FortiToken MFA

Configure a FortiGate IKEv2 VPN Linux concentrator with FortiToken MFA. This guide covers strongSwan client setup, EAP authentication, and port 443 traversal for remote...

20 July, 2026

Deploying FRRouting on Ubuntu 24.04 LTS: Production BGP and OSPF Routing

Configure FRRouting on Ubuntu 24.04 to build a production router. Learn step-by-step setup for OSPF backbone and eBGP sessions with route filtering and verification.

19 July, 2026

Building a Stateful Host Firewall and NAT Gateway with nftables

Build a production nftables stateful host firewall and NAT gateway. Get atomic, dual-stack configs for Linux that survive reboots and reloads cleanly.

19 July, 2026

FortiGate VDOM Deep Dive: Designing, Deploying, and Operating Multi-VDOM on FortiOS

Configure FortiGate multi-VDOM for tenant isolation. Learn to enable multi-VDOM mode, assign interfaces, and build inter-VDOM links with working CLI examples.

28 May, 2026

Kasm Workspace on Ubuntu Linux; How to deploy and configure VPN

Deploy Kasm Workspace on Ubuntu Linux using the official script. Configure OpenVPN egress providers to hide OSINT artifacts and protect your real IP address.

16 May, 2026

Understanding the Linux diff Command: A Practical Guide

Master the Linux diff command. Learn to read normal and unified output, compare directories, and apply patches with practical examples.