Ubuntu Server Hardening — Part 1: The Essentials

Mon, 11 May 2026 00:00:00 +0000

This is the first post in a three-part series on hardening a public Ubuntu server.

In the previous post we secured SSH: replaced password login with key-based authentication, disabled root, and restricted which users can connect at all. That alone eliminates the majority of attacks targeting internet-facing servers.

But SSH is one layer. This series adds three more layers per post, ordered by how quickly you can apply them and how much impact they have. Start here — these three take less than fifteen minutes and protect against the most common active threats.

Hardening on Tobias Theel | Senior Software Engineer

Ubuntu Server Hardening — Part 1: The Essentials