RPiDAC - producing audio without a sound card

Excuse me…?

Yea, you read right. How to produce sound using a Raspberry Pi, without using its integrated sound card.

This idea was originally created for an IoT course I took; I thought it would be amusing for wider audiences as well, so I decided to write a blog post about it as well.


Attack of the SSH Bots - observations on SSH brute-forcing attempts


As publicly known, I have an active home server for a variety of purposes. I recently did something that could be said to be a major renovation; a big part of the internal software setups were replaced completely, and all of them were substantially updated or at least refactored to be better suitable for my current needs.

It is considered to be common knowledge that SSH bots are constantly on the hunt for vulnerable hosts. It is also an equally well known fact for me that my server was probed by these bots (as shown on firewall logs), but I had not systematically collected any statistical data about them.

So, for personal interest, I set up an automated statistical logger for SSH services. It observes SSH probing attempts, and jots down information in a easy-to-process format. The results were quite interesting indeed, in my personal opinion.

Note that all of these observations are about password-based login attempts. Even though my logging system would have logged failed public-key login attempts, absolutely zero of them occurred. This is an interesting observation in and of itself.