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Dan Higgins
Dan Higgins

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“Houston, We’ve Got a Firewall Problem” — A Day in the Life of a RHEL 9 Sysadmin

It’s Monday morning. You haven’t finished your first coffee, and the boss yells:
“We can’t access the web server!”

You squint at your screen like a hungover raccoon and SSH into the server. Welcome to life as a Linux sysadmin on RHEL 9.

Today, your mission: Fix the firewall, check SSH, and avoid accidentally nuking production.

📚 Table of Contents

Step 1: “Is This Thing Even Running?”

Let’s see what your firewall is doing. It might be sleeping on the job.

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Great, your firewall is alive and well — maybe too well. Let’s check if it’s blocking your traffic like an overzealous nightclub bouncer.

Step 2: Peek Behind the Firewall

Check which zones and services are active. This is like asking your firewall what doors it's guarding.

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No http or https? No wonder your site’s ghosting everyone.

Step 3: Let the Web Traffic In

Tell the firewall to stop being such a hermit and allow web traffic:

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Boom — doors open, dragons allowed (as long as they speak HTTP).

Step 4: Check SSH Before You Lock Yourself Out

Before you do anything reckless like restarting the firewall or rebooting, double-check SSH is running, or you'll end up locked out like a medieval jester.

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Running? Good. If not:

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Because nothing says "professional sysadmin" like bricking your own remote server.

Step 5: Celebrate with a Log Check

Check the logs to make sure everything didn’t silently explode behind the scenes:

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Look for red flags, weird errors, or secret plots against your uptime.

Why This Stuff Actually Matters

Funny stories aside — these situations happen every single day in the real world. Firewalls misconfigured, SSH services down, ports blocked — it’s all part of the sysadmin life.

Understanding how to use systemctl, manage firewalld, and troubleshoot services on RHEL 9 is crucial not just for passing certifications, but for actually doing the job. Reading theory is great, but real-world scenarios like this one solidify your knowledge and build confidence.

By getting hands-on, you’re not just studying — you’re becoming the person companies call when everything goes sideways. And trust me, they will go sideways.

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