System Essentials
The foundation of Linux knowledge. Understanding these concepts makes everything else click.
Overview
Section titled “Overview”This section covers the core building blocks of Linux that every DevOps/SRE professional needs to understand. These aren’t just theoretical concepts—they’re the reality you interact with every time you run a command or debug an issue.
Modules
Section titled “Modules”| # | Module | Description | Time |
|---|---|---|---|
| 1.1 | Kernel & Architecture | Kernel vs userspace, modules, why containers share kernels | 25-30 min |
| 1.2 | Processes & systemd | PIDs, process lifecycle, signals, systemctl, units | 30-35 min |
| 1.3 | Filesystem Hierarchy | /etc, /var, /proc, /sys, inodes, mount points | 25-30 min |
| 1.4 | Users & Permissions | UIDs, groups, rwx, setuid, sudo, least privilege | 25-30 min |
Why This Section Matters
Section titled “Why This Section Matters”Every single thing you do on Linux touches these concepts:
- Running a container? The kernel provides process isolation
- Debugging a crash? Understanding processes helps you investigate
- Checking configuration? You need to know where files live
- Running kubectl? Permissions determine what you can do
Prerequisites
Section titled “Prerequisites”None. This is where you start.
Key Takeaways
Section titled “Key Takeaways”After completing this section, you’ll understand:
- How the Linux kernel manages everything (and why containers share it)
- What processes are and how they’re managed by systemd
- Where everything lives in Linux (and why it’s organized that way)
- How users and permissions protect systems
Related Sections
Section titled “Related Sections”- Next: Container Primitives — Apply these concepts to containerization
- Uses: These concepts underpin everything in the track