Linux server tutorials
Step-by-step tutorials for a Linux server: VPNs, web servers, databases, containers, security and backups. Each one names the distributions it was tested on.
2 of 45 tutorials in Security tested on Debian 13 Stable
How to create a sudo user and disable root login on Ubuntu and Debian
Add a normal user with sudo rights on Ubuntu or Debian, give it your SSH key, then stop root logging in over SSH without locking yourself out.
How to install CrowdSec on Ubuntu and Debian
Install the CrowdSec engine and its nftables firewall bouncer, watch SSH and nginx logs, allowlist your own addresses, and see what it blocks.