LinuxSecurity.com

We spend most of our time chasing endpoint infections and identity abuse. That's where the alerts are. That's where the tooling is. Meanwhile, the device that routes every login, session cookie, software update, and SaaS request can sit untouched for years.

Most of us have pulled something from the AUR because it was faster than packaging it ourselves. You need a tool; it's there, it builds cleanly, and the system keeps moving. No alerts. No obvious red flags. That's usually how supply chain issues begin, not with explosions but with convenience.

Intrusion detection and prevention systems are often treated as interchangeable. IPS is often described as IDS with blocking turned on. That sounds simple, but the moment traffic runs inline, mistakes start breaking real connections. IDS watches traffic and reports what looks suspicious, while IPS sits in the path and can block connections as they happen. Let's walk through that shift using simple Snort examples. The goal is to show what breaks once blocking is enabled and why that changes how you operate the system.

Most of us meet SELinux when something breaks. A service won't start, a port won't bind, a perfectly reasonable file write gets blocked, and the quickest path back to green looks like turning it off. That first experience sticks, and it shapes how people talk about SELinux afterward.