Day 1 — Linux for DevOps: The Mindset Shift

This content originally appeared on DEV Community and was authored by Dan Higgins

Welcome to Day 1 of 30 Days of Linux for DevOps!
If you’re here, you already know something important:

DevOps isn’t about tools… it’s about knowing what’s happening under the hood.
And the engine under almost every cloud service, container, CI/CD runner, and Kubernetes node is Linux.

Today isn’t about memorizing commands.
It’s about building the DevOps mindset that connects Linux → Cloud → Automation → Systems thinking.

So let’s kick things off.

📚 Table of Contents

• What makes Linux for DevOps different from Linux for beginners?
• Today’s Goal: Learn how DevOps engineers observe a system
• See where you are (DevOps style)
• Navigate like you're working in production
• See what your system is doing right now
• View logs like an SRE
• Today’s DevOps mini challenge
• Day 1 Wrap Up

What makes Linux for DevOps different from Linux for beginners?

Beginners learn commands so they don’t feel lost.
DevOps engineers learn commands because they need to debug, automate, optimize, and control systems at scale.

Here’s the difference:

Beginner:

“ls shows files.”

DevOps Engineer:

“ls -lh tells me file sizes, permissions, ownership, and helps me spot weird stuff in log directories.”

Same command.
Different purpose.
Different mindset.

Today’s Goal: Learn how DevOps engineers observe a system

Before you automate anything, deploy anything, or build anything…
you must know how to look at a system and understand what’s going on.

So today we cover the DevOps essentials:

✔ What's running
✔ What's using resources
✔ How to find logs
✔ How to navigate like a pro

Let’s jump in.

See where you are (DevOps style)

Forget plain pwd.
We add context:

Why this matters:
Every server, container, or Kubernetes node could be different.
A DevOps engineer always checks:

Who am I? (User, root, restricted?)

Where am I? (Directory? Partition? Container?)

What machine am I on? (Production? Staging? EC2?)

This prevents mistakes like… deploying to the wrong environment.
(I'm just glad it's in the sandbox!)

Navigate like you're working in production

Skip the basics — let’s use flags DevOps engineers actually use:

Why?
-a shows hidden files (very important for configs).
-h shows sizes you can read (1K, 10M, 1G).
-l shows ownership + permissions.

This is how you spot things like:

log files exploding in size

weird hidden scripts

wrong ownership on app directories

See what your system is doing right now

This is where DevOps thinking really begins.

✔ Check running processes

✔ Live system view (your new best friend)

Why this matters:
When a service is slow, a pod is failing, or a CI runner is stuck —
your first job is to observe system behavior.

CPU spikes?
Memory leak?
Zombie processes?
You’ll see it here.

View logs like an SRE

Logs are where DevOps engineers spend half their life.
Let’s get comfortable with them from Day 1.

Try this in /var/log:

Then open a log:

Real-time log streaming:

This is how you troubleshoot:

failing services

permission issues

network errors

kernel events

container crashes

If you can read logs, you can fix anything.

Today’s DevOps mini challenge

Create a simple “system snapshot” script and save it:

Make it executable and run it:

Congrats — you just created your first DevOps-style diagnostic tool!

Day 1 wrap up

Today you didn’t just learn some commands.
You learned how DevOps engineers observe, analyze, and understand a system before doing anything else.

This mindset will guide you through the next 29 days — and into real DevOps work.

See you tomorrow for Day 2: “Navigating Logs Like an SRE.”

Let’s keep building something real

This content originally appeared on DEV Community and was authored by Dan Higgins