THE DEV BENCH
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Linux Foundation Certified System Administrator · LFCS

One workspace for passing the LFCS — a fully hands-on, performance-based exam (you solve real tasks on a live command line, no multiple choice). The labs are the real work; the five domain decks and the recall exam lock in the commands and concepts behind them. Authored against the official Linux Foundation domains.

The honest read: the LFCS is 100% hands-on — you fix and configure a real system at the prompt, no multiple choice. So the labs are the real study plan; the decks and practice exam exist to lock in the exact commands, flags, and file locations you need in reflex memory. Front-load Operations Deployment and Networking — together they're half the exam.

Deep work · LFCStotal
or log

The exam at a glance

verified July 2026
Cost$445 (exam + 1 retake)
FormatPerformance-based · live CLI · online proctored
Duration2 hours
Passing score~67%
Validity3 years
EnvironmentUbuntu or CentOS/RHEL, your choice

Passing score and validity are shown as standard/as-seen — the Linux Foundation doesn't publish an exact cut score. Confirm current cost, format, and policy on the official certification page before you book.

Certification roadmap

sequence
LFS101Introduction to LinuxOptional prep

Free self-paced course (Linux Foundation / edX)

Recommended, not required. Do it first if the basics (filesystem, shell, permissions, processes) are shaky. Free — see resources below.

LFCSCertified System AdministratorThe goal

Performance-based · live CLI · 2 hrs · ~67% to pass † · 3-year validity † · $445 (1 free retake)

The target of this workspace. 100% hands-on — you solve real tasks on a live command line, no multiple choice. Proves you can administer a Linux system: manage users, storage, networking, and services under time pressure.

CKACertified Kubernetes AdministratorNatural next

Performance-based · advanced

Builds directly on LFCS — Kubernetes admin is Linux admin plus orchestration, same performance-based style and the same Killercoda practice ecosystem. There's a full CKA workspace here too.

Exam domains — weight your study by these

official weights

The five official Linux Foundation domains, in weight order. Under each: the recall deck and the hands-on lab where you actually practice it — so you can go straight from “what's tested” to “where I drill it.”

Operations Deployment25% of the exam

systemd services & targets, the boot process & GRUB, scheduling (cron/at/systemd timers), package management, kernel modules & sysctl, process priorities, and SELinux basics.

Networking25% of the exam

IP config & routing (the `ip` suite), persistent config (NetworkManager/netplan), DNS resolution, firewalls (firewalld & nftables), SSH, port inspection (`ss`), and time sync.

Storage20% of the exam

Partitions & filesystems, mounting via /etc/fstab (by UUID), LVM (PV→VG→LV) & growing volumes, swap, ext4-vs-XFS resizing, quotas, RAID, and LUKS encryption.

Essential Commands20% of the exam

File operations, text processing (grep/sed/awk), permissions & ownership (numeric + special bits), links, archives & compression (tar/gzip), find, and globbing.

Users and Groups10% of the exam

Account & group lifecycle, the usermod -aG append trap, password/account aging, the passwd/shadow/group files, and sudo via sudoers.

Operations Deployment (25%) + Networking (25%) = half the exam. Because it's performance-based, practice by DOING each task on a live shell, not by memorizing flags. The five decks carry 106 cards distributed to match these weights.

Hands-on labs — the real practice

live · do these most

The LFCS is solving real tasks at the prompt — so this is where you should spend most of your time. Both run in the browser.

Note: the in-browser labs open on Killercoda. Auto-grading turns on once the Dev Bench Killercoda account is connected; until then, use them as guided practice and check your work against the scenario steps. For always-on graded reps, the free killercoda.com Linux playgrounds are the closest free thing to the real exam's live-shell format.

Flashcard decks — the recall layer

5 decks · 106 cards
Operations Deployment (25%)26 cards — the biggest domain. systemd (start vs enable, mask, targets, daemon-reload), the boot process & GRUB, cron/at/systemd timers, package management, kernel modules & sysctl, signals & niceness, and SELinux. Start here; it's a quarter of the exam.

The other four domains

Practice exam

live · 85-question pool
LFCS — Linux Sysadmin Practice ExamA fresh 40-question draw each attempt from a domain-weighted 85-question pool, scored at 70%. Command/concept MCQs with worked explanations and a per-domain weak-area breakdown. Progress saves in your browser — no login.

The real LFCS is hands-on, so this MCQ quiz is a recall/weak-area tool — it does not replace the labs. Use it to find gaps, then close them at the prompt.

Skill map — where to practice each thing

the workspace
SkillPractice withStatus
Solve real admin tasks at a live shell (all domains)Linux lab — Learn + Break-fixready
Shell fluency, pipelines & text processing (Essential Commands)Bash labready
Commands, flags & file locations in reflex memoryThe 5 LFCS decks (106 cards)ready
Exam-format recall & weak-area findingLFCS practice exam (draw 40, pass 70%)ready
Full disposable Linux environments under a timerkillercoda.com (external, free)external

A study routine

  1. 1.Live over notes: for every command you learn, run it on a real shell until the syntax is reflex. Performance exams reward speed and muscle memory, not recognition — spend most of your time in the Linux lab and on Killercoda.
  2. 2.Front-load Operations Deployment (25%) and Networking (25%) — half the exam. Do each deck, then reproduce every command in the Linux lab.
  3. 3.Drill storage as a whole workflow: partition → mkfs → mount → fstab (by UUID) → LVM grow. It's 20% and it's where timing pressure bites; `lvextend -r` and the XFS-can't-shrink rule are classic traps.
  4. 4.Use the practice exam to find weak domains, then close them at the prompt — the per-domain breakdown tells you exactly where to drill.
  5. 5.Practice under a timer. The exam is 2 hours of tasks — build the habit of solving cleanly, using `man`/`tldr` on-box, and moving on. Hit the exam's ~67% on the practice quiz three times before you book.

Curated resources — free-first

verified July 2026

Everything you need to LEARN the LFCS is free (the official domains + LFS101 + Killercoda). Only the exam voucher and the optional courses cost money. Every link checked live (July 2026); prices/versions shift, so treat costs as “as seen.”

Start your reps