Intro Unless you’re a sysadmin or worked with GNU/Linux servers for a long time, it’s very possible that you’ve never heard about a chroot jail. This is a very old topic, seriously, I learned how to create a jail about 15 years ago, yet it remains a very useful concept today. Let’s say you have your own server, and you decide to mount your own mini-hosting project. Somehow, you need to give your users access via SSH so they can do their stuff.
Intro Days ago, I bought my first VPS with Debian 12 installed. Just a few days after it was up and running, I began checking the system logs, where the SSH service caught my attention. To my surprise, there were several attempts to connect to port 22, including some brute-forcing attempts to access users that didn’t exist on my server. I mean, I know it’s a public IP and the World Wide Web, but come on, not even 48 hours online and I’ve already had several intrusion attempts, mostly coming from Asia.