We're in Week 4 of my Linux series, and this week I want to start with a question: have you ever had your laptop fan suddenly start screaming while you were doing absolutely nothing?
I have. Many times 😂 And before this week, I'd just stare at it, close a few tabs and hope for the best. This week, some few chapters i revisited gave me the tools to actually ask the machine what it was doing. Come with me, because the story gets interesting.
First, I Taught the Computer to Do My Chores
Chapter 11 was shell scripting. Think about how much of our day is repetitive: backing up files, renaming things, running the same checks again and again. A script lets you write those steps once and never think about them again. That's basically what every app on your phone does for you, just on a smaller scale.
I went through variables, user input, arguments, exit codes, conditionals and loops. The routine is always the same:
nano myscript.sh # write the script
chmod +x myscript.sh # make it executable
./myscript.sh # run it
Tip: Watch the exit code. A 0 means "all good". Anything else means something went wrong. Automation that fails silently is how small problems become big ones, and in security, silent failures are exactly what attackers hope for.
Then I Asked My Machine to Introduce Itself
Chapter 12 was hardware: CPU, RAM, motherboard, storage and drivers. We buy laptops by specs, but how often do we check what is really inside? Linux will tell you straight, no sales pitch:
lscpu # displays CPU information
free -m # shows memory usage in megabytes
lspci # lists PCI devices
lsusb # lists USB devices
Tip: Plugged something in and it's not working? Run lsusb before blaming the cable. If the system can't even see the device, the problem is somewhere else.
And Then It Showed Me Its Diary
This is where it got juicy 👀
Chapter 13 showed me that your computer quietly writes down almost everything it does. Every process, every error, every strange event. It's like a diary, and Linux lets you read it.
These are the places to look:
/proc # information about processes and the kernel
/dev # files that represent devices
/sys # information about devices and the kernel
/var/log # where most system logs live
And these are the commands that read it for you:
ps aux # view running processes
top # monitor system activity live
dmesg # kernel messages
journalctl # investigate system logs
So that screaming fan? top would have shown me exactly which process was eating my CPU. Mystery solved in ten seconds, no panic needed.
In a world where we hear about data breaches almost every week, knowing how to read your own system's logs is a real superpower. Most people only look at logs after something has gone wrong. The better habit is to look before.
Finally, I Followed the Trail Out to the Internet
Chapter 14 was networking, and it connects to everything. Every video call, every online payment, every message you send travels through the same ideas: IP addresses (IPv4 and IPv6), DNS, DHCP, routers and servers.
ip addr show # displays network interfaces and IP addresses
ping # tests network connectivity
host / dig # investigate DNS information
ssh # secure remote access to another system
I also revisited two small files that do big work: /etc/hosts (local name-to-address mappings) and /etc/resolv.conf (which DNS servers your system uses).
Tip: Next time the internet "isn't working", don't just restart the router and pray. Go in order: ip addr show to check your address, ping to test the connection, dig to check DNS. You'll find the real problem much faster, and you'll look very smart doing it
The Honest Part
top and journalctl looked like a wall of text the first time I opened them 😭 My brain just froze. What worked was slowing down and reading one line at a time, instead of trying to understand everything at once. It's a good lesson for life, honestly.
What I'm Taking Away
Our lives now run on devices, apps and networks we barely think about. Linux sits underneath a huge part of that, from servers to phones to the cloud. This week reminded me that when you understand what your system is doing, you stop being a passenger and start being the driver. And in cybersecurity, that's the whole game.
A little progress at a time still counts. 💜
Now tell me: what's the strangest thing your computer has ever done that made you say "what is going on?" Drop it in the comments, I'd love to hear the stories 👇
The Duchess of Hackers
Full-Stack Developer | Digital Marketer | Cybersecurity Enthusiast