When I was preparing for the LFCS, I kept running into the same generic advice: “know your basics,” “practice a lot.”
Helpful, sure — but not exactly actionable.
So in this post, I want to share what actually worked for me and helped me pass the LFCS with 95/100. Hopefully this saves you some stress and gives you a clearer path forward.
Start with KodeKloud
KodeKloud mock exams were a lifesaver. They replicate the exam style really well and got me comfortable with solving CLI-based tasks under time pressure.
If you’re new to timed, hands-on exams, start here. It’s the best warm-up you can give yourself.
Use Killer.sh Wisely
With the LFCS purchase, you get two free Killer.sh sessions. My advice: don’t burn through both immediately.
- Use one before your actual exam — ideally twice by resetting it.
- Save the other in case you need a retake.
Why? If you don’t pass the first time, you get a free second attempt, and having a fresh Killer.sh session can be a real confidence booster.
Know Your Weaknesses
Everyone has weak spots. For me, it was iptables and storage management. The good news? Once you put in the practice, they’re not as scary as they seem.
1. iptables
There was a heavy question around iptables. If you’re not comfortable writing rules from scratch, this can cost you the exam.
Focus on being able to:
- Block and allow ports
- Set up basic NAT and forwarding
- Save and restore rules
2. Storage (LVM, Disks, Mounting)
Understand the flow from physical disks to logical volumes:
- Create partitions
- Format them
- Mount them
- Extend volumes and resize filesystems
Get Comfortable with VIM
Even if you’re not a daily VIM user, being able to jump quickly around a file is a huge stress-saver during the exam.
The shortcuts I used most often:
/word— search for a word:set nu— show line numbers:30— jump to line 30Shift + $— end of current lineShift + G— end of fileg— beginning of file
A couple of hours of practice here will pay off big time.
Schedule Your Exam in the Morning
Nothing fancy here — just common sense. Take it when you’re freshest, not after a long workday.
Morning exams = fresh brain, fewer distractions, better focus.
Always Check Which Host You’re On
This one bit me. I actually solved a task on the wrong host and got zero points.
Don’t repeat my mistake — double-check every time you SSH into a new machine. In my exam, there were 17 tasks and 17 machines, one per task.
Use apropos
Forget a command or tool? Don’t panic. Just use:
apropos "selinux"
or:
man -k selinux
This saved me multiple times when I blanked on a command name.
Don’t Rush — You Have Two Chances
The LFCS is tough but fair. Think of your first attempt as a real-world lab:
- If you pass, fantastic.
- If not, you get another chance, and you’ll go into it with way more clarity.
Either way, every hour you spend practicing makes you a stronger sysadmin.
Final Thoughts
The LFCS is a hands-on, real-world challenge — and that’s what makes it valuable. Take your time, practice your weak spots, and remember: even if you stumble, you’ll come back stronger on your second try.