Fix broken Kubernetes. Walk into your CKA ready.
Exam-style tasks on a live cluster in your browser: a Service with no endpoints, an Ingress that answers 404, a NetworkPolicy that blocks DNS. A grader checks the cluster itself, and timed mock exams follow the official format for the CKA, CKAD and CKS, with a new draw every attempt. Linux, Git and shell labs are included too.
Free to start. No credit card, nothing to install. Independent practice, not affiliated with the Linux Foundation or CNCF.
Practice on the tools infrastructure teams use
LinuxShellGitDockerKubernetesCI/CDTerraformThe skills infrastructure jobs actually test
110 hands-on labs and 167 quiz questions today, written from scratch. New topics ship in the order learners ask for them.
Linux administration
20 hands-on labs, 28 quizzes
Files, permissions, users, processes, logs and scheduling on a real server.
Practice LinuxShell & Bash scripting
9 hands-on labs, 5 quizzes
Pipelines, jq, and scripts that are safe to run from cron and CI.
Practice ShellGit
12 hands-on labs, 16 quizzes
Branches, merges, conflicts and rescuing history without breaking teammates.
Practice GitKubernetes
69 hands-on labs, 48 quizzes
Workloads, Services, storage, RBAC and troubleshooting, CKA style.
Practice Kubernetes
Theory today, hands-on labs next
- Docker & containers
12 quiz questions
- Cloud & AWS
26 quiz questions
- Networking
8 quiz questions
- CI/CD & GitHub Actions
6 quiz questions
- Terraform & IaC
18 quiz questions
Python for DevOps
In development
Go for infrastructure
In development
Missing a topic?
Ansible, Azure, observability, databases…
How a problem works
- 1
Read a real-world task
Every problem is a situation you would meet at work, with names, ports and values randomised just for you — so answers can't be copied.
- 2
Solve it on a real machine
A fresh, isolated Linux sandbox opens in your browser. Use any approach: the grader never checks which commands you typed, only the result.
- 3
Submit, then learn the why
See exactly which requirements pass or fail — no hints. Once you're done, the full solution explains the reasoning and the classic mistakes.
Fix “Permission denied” on service data
EasyGrader waiting for submit
- state directory is owned by amir
- ledger.db is owned by amir
- Permission bits were left alone (750 / 640)
- amir can write into the state directory
Mock exams where you choose how you're graded
Timed exams on one shared machine, with new tasks every attempt. Check each task the moment you finish it — or rehearse the real thing and get graded only at the end. Either way you get partial credit, your weak skills and every solution.
- Check as you go: see which requirements pass, fix, check again
- Graded at the end: the certification-style rehearsal
- Mock, level and theory exams — or build your own
A coach that knows what to practise next
Every problem is tagged with the skills it exercises. BrokenCluster follows how each skill is growing and builds a short plan every day: skills to grow, one review, one stretch. Every solve earns XP, levels and milestones — reading a solution never costs you anything.
Today's plan
- medium
Grant exactly one command via sudo
Skill to grow: sudo
- medium
Resolve a merge conflict
Skill to grow: merging
- easy
Find files by name, size and age
Review
- hard
Find the commit that introduced a bug
Stretch
Weekly contests with a certificate for every place
Every week, a live contest on real machines in three divisions — from mostly theory to mostly hard hands-on work. Finish 1st or 150th: you get a verifiable certificate with your place to share, and season points that only go up.
This season's board is wide open
Take part in the next contest and your name is on it.
Roadmaps from first command to job-ready
Ordered paths per topic that mix labs and theory, with progress you can see — and a level exam to prove it. Verifiable BrokenCluster certificates are next.
Teaching Linux, DevOps or cloud?
Give every student a safe machine and automatic grading. We build problem sets around your curriculum and datasets, with class leaderboards and reports that show who is stuck on what.
- Custom problem sets for your course
- Instructor dashboard and progress reports
- Private class leaderboards
- Free pilot semester for early partners
- Plan a pilot with us
Free to start. Pro when you're serious.
Pro costs less than one month of most course platforms, and you can cancel any time.
Free
$0
- Most labs and quizzes
- 5 lab sessions a day
- Weekly contests with certificates
Pro Best for job seekers
$9/month
- Every problem and roadmap
- Every mock and level exam, plus your own
- Longer, near-unlimited lab sessions
Questions people ask
Do I need a cloud account or a powerful computer?+
No. Labs run on our servers in isolated sandboxes. You only need a browser. Cloud provider topics are practiced with quizzes now and with simulated CLIs later — never on a real account that could bill you.
Why no hints?+
Real incidents don't come with hints. The grader tells you precisely which requirement fails, never how to fix it. When you are done — or stuck — the full solution explains every step. Reading it never costs you anything: solve the lab afterwards and you still earn the full XP.
Is this a certification prep site?+
It's practice for the skills behind certifications like CKA, LFCS or cloud associate exams, with original problems only. We are not affiliated with any certification body and never use real exam questions.
What happens to the commands I type?+
They are stored with your attempt so we can see where people get stuck and improve problems — and so the grader can explain failures better in the future. Details are in the privacy policy, and you can export or delete your data any time.
Can I cancel Pro?+
Yes, in one click from Settings. You keep Pro until the end of the period you paid for.
Your first lab takes about five minutes.
Pick a problem, open the terminal, and see how far you get.