Ubuntu on Servicios Rogeliowar

Fail2ban to protect SSH and Nginx: practical configuration on Ubuntu

Thu, 30 Apr 2026 00:00:00 +0000

The Problem: Brute Force Attacks
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After exposing my Ubuntu server to the internet, I spent a night reviewing logs. SSH received failed login attempts every second. Nginx also had suspicious requests to common routes. I needed something to block these attempts automatically. Fail2ban was my solution.

Installation
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sudo apt update
sudo apt install fail2ban
sudo systemctl start fail2ban
sudo systemctl enable fail2ban

Verify that it’s running:

SSH authentication by public key: disable passwords on Ubuntu Server

Thu, 30 Apr 2026 00:00:00 +0000

Why Switch to Key-Based Authentication
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After months of maintaining a home server with open SSH access, I got tired of brute force password attacks. Switching to public key authentication was the best security decision I made. Keys are mathematically impossible to crack through brute force, while passwords are always a target.

SSH Key Generation
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First, generate a key pair on your local machine (not on the server):

Ubuntu on Servicios Rogeliowar

Fail2ban to protect SSH and Nginx: practical configuration on Ubuntu

The Problem: Brute Force Attacks #

Installation #

SSH authentication by public key: disable passwords on Ubuntu Server

Why Switch to Key-Based Authentication #

SSH Key Generation #

The Problem: Brute Force Attacks
#

Installation
#

Why Switch to Key-Based Authentication
#

SSH Key Generation
#