In the server world, it’s a foregone conclusion that ports shouldn’t be exposed to the greater Internet if they don’t need to be. There are malicious bots everywhere that will try and randomly access anything connected to a network, and it’s best just to shut them off completely. If you have to have a port open, like 22 for SSH, it’ll need to be secured properly and monitored so that the administrator can keep track of it. Usually this is done in a system log and put to the side, but [Nick] wanted a more up-front reminder of just how many attempts were being made to log into his systems.
This build actively monitors attempts to log into his server on port 22 and notifies him via a numerical display and series of LEDs. It’s based on a Raspberry Pi Zero W housed in a 3D-printed case, and works by interfacing with a program called
fail2ban running on the server.
fail2ban‘s primary job is to block IP addresses that fail a certain number of login attempts on a server, but being FOSS it can be modified for situations like this. With some Python code running on the Pi, it is able to gather data fed to it from
fail2ban and display it.
[Nick] was able to see immediate results too. Within 24 hours he saw 1633 login attempts on a server with normal login enabled, which was promptly shown on the display. A video of the counter in action is linked below. You don’t always need a secondary display if you need real-time information on your server, though. This Pi server has its own display built right in to its case.