Security on Manzolo Code Notes

SPF, DMARC and DKIM: The Email Security Triad

Mon, 16 Feb 2026 10:00:00 +0200

Understanding how SPF, DMARC, and DKIM work to protect your emails from spam and phishing

GPG Bash Playground

Sun, 28 Sep 2025 00:00:00 +0200

GPG Bash Playground Guide

Introduction

The GPG Bash Playground is an educational Bash script that demonstrates the practical use of GPG (GNU Privacy Guard) for key generation, public key exchange, encryption, and decryption. The script simulates a secure communication scenario by creating three users (Alice, Bob, and Carol), generating their GPG keys, exchanging public keys, and performing encrypted message exchanges. It includes comprehensive logging, error handling, and a debug mode for detailed output. This guide explains how to set up, run, and understand the script’s functionality.

SSH Forward Tunneling

Fri, 26 Sep 2025 10:00:00 +0100

SSH Forward Tunneling Guide

Introduction

SSH forward tunneling (also known as local port forwarding) allows you to securely connect to a remote service through an SSH server, making it appear as if the service is running on your local machine. This is useful for accessing services on a remote server or another machine in a secure network that aren’t directly accessible.

In this guide, we’ll cover the basics of SSH forward tunneling, explain how it works, and provide practical examples.

Uncomplicated Firewall

Fri, 26 Sep 2025 10:00:00 +0100

Ubuntu UFW Firewall Guide

Introduction

UFW (Uncomplicated Firewall) is a user-friendly interface for managing iptables firewall rules on Ubuntu systems. It simplifies the process of configuring firewall settings, making it accessible for beginners and efficient for advanced users. This guide covers essential UFW commands, practical examples, and tips for securing your Ubuntu server.

What is UFW?

UFW is a front-end for iptables, designed to make firewall configuration straightforward. It allows you to manage inbound and outbound network traffic by defining rules based on ports, protocols, and IP addresses.

Network Traffic Analysis with Wireshark (Debian/Ubuntu)

Sat, 04 Oct 2025 13:25:00 +0200

Network Traffic Analysis with Wireshark (Debian/Ubuntu)

Introduction

Wireshark is a powerful open-source tool for capturing and analyzing network traffic, widely used for debugging network issues, monitoring traffic, and security analysis. This guide explains how to install Wireshark on Debian/Ubuntu, capture traffic on a network interface, apply filters, and analyze packets for common protocols like HTTP and TCP. It includes practical examples for troubleshooting connectivity, inspecting web traffic, and identifying bandwidth usage.

LUKS Disk Encryption Management Guide (Debian/Ubuntu)

Fri, 03 Oct 2025 14:00:00 +0200

LUKS Disk Encryption Management Guide (Debian/Ubuntu)

Introduction

LUKS (Linux Unified Key Setup) is a standard for Linux disk encryption that provides a platform-independent way to encrypt block devices, such as partitions or entire disks. It supports multiple passphrases (keys), secure key derivation, and integration with other storage layers like LVM or ZFS. This guide explains how to create, modify, and manage encrypted disks with LUKS on Debian/Ubuntu systems, covering setup, key management, mounting, and maintenance.

OpenVPN Server Installation and Configuration Guide (Debian/Ubuntu)

Sat, 04 Oct 2025 11:00:00 +0200

OpenVPN Server Installation and Configuration Guide (Debian/Ubuntu)

Introduction

Setting up an OpenVPN server allows secure remote access to your network or resources. This guide explains how to install an OpenVPN server on Debian/Ubuntu, generate certificates and keys, configure the server, create user/client configurations, and connect from a client. It includes steps for creating multiple users and testing connections, making it ideal for home servers, small businesses, or secure remote access.