Problems

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26 of 277 problems

Title	Topic	Acceptance	Difficulty	XP
Schedule a Nightly Cron JobInstall a daily job in another user's crontab at an exact time.easyLinux10 XP	Linux	New	easy	10
Find What Is Filling the DiskTrack down the subdirectory consuming the most space, past a decoy full of tiny files.easyLinux10 XP	Linux	New	easy	10
systemd Timers vs cronA backup must run daily at 02:00 on a VM that is often powered off overnight. If the run is missed, it should happen soon after the next boot. Which systemd timmediumLinux5 XP	Linux	New	medium	5
Loading Kernel ModulesYou need to load the vfiopci kernel module, which depends on other modules that are not loaded yet. Which command handles the dependencies for you?easyLinux3 XP	Linux	New	easy	3
Undo a Bad Commit Without Rewriting HistoryA shared branch contains a commit that broke production. Undo just that commit safely.mediumGit20 XP	Git	New	medium	20
Find the Commit That Introduced a BugSearch a long history to find exactly which commit added a dangerous setting.hardGit40 XP	Git	New	hard	40
Running as Non-rootWhy is it recommended to add a USER instruction (a non-root user) to production Dockerfiles?mediumDocker5 XP	Docker	New	medium	5
The Problem with :latestWhat is the main risk of deploying images referenced as myapp:latest?easyDocker3 XP	Docker	New	easy	3
Fix Pods Stuck in PendingA Deployment asks for more CPU than any node has. Find out why its Pods never start and right-size the requests.easyKubernetes10 XP	Kubernetes	New	easy	10
Schedule a CronJob and Run It NowCreate a CronJob with a precise schedule and history settings, then trigger a one-off Job from it that completes.mediumKubernetes20 XP	Kubernetes	New	medium	20
Run a Workload on a Dedicated NodeA node is reserved with a taint. Get one Deployment onto that node, and only that node, while everything else stays off it.mediumKubernetes20 XP	Kubernetes	New	medium	20
Build a Production Overlay with KustomizeReuse shared manifests without touching them, with an overlay that changes the namespace, replicas, image and labels.mediumKubernetes20 XP	Kubernetes	New	medium	20
Pending on Purpose, Pending by MistakeA batch workload must run on the node reserved for it, but its Pods never get placed. Fix the workload, not the nodes.mediumKubernetes20 XP	Kubernetes	New	medium	20
Stuck in PendingA new release never starts; its Pods sit in Pending. Read the scheduler's events, find the cause and fix it the right way.mediumKubernetes20 XP	Kubernetes	New	medium	20
Patch a Chart Without Forking ItA vendor chart has no values for the scheduling rule your platform requires. Install it with a Kustomize post-renderer that adds it, so the change stays part of the release.hardKubernetes40 XP	Kubernetes	New	hard	40
Secrets as Files, Not Environment VariablesAn app reads its database password from an environment variable, where it leaks into crash dumps and debug output. Move it to a read-only file only the app's user can read.easyKubernetes10 XP	Kubernetes	New	easy	10
Who Can Read the Production Secrets?Audit RBAC across the cluster to find the ServiceAccount that can read Secrets in the payments namespace without needing to, record it, and revoke exactly that access.mediumKubernetes20 XP	Kubernetes	New	medium	20
Restoring an etcd SnapshotOn a kubeadm cluster you took a backup with etcdctl snapshot save /opt/snap.db. After an accidental deletion you run etcdutl snapshot restore /opt/snap.db --dathardKubernetes8 XP	Kubernetes	New	hard	8
Requests and LimitsA container has resources.requests.memory: 256Mi and resources.limits.memory: 512Mi. Which statement is correct?mediumKubernetes5 XP	Kubernetes	New	medium	5
Kustomize Overlaysbase/ holds a Deployment and a Service. Production needs 5 replicas and the image tag 2.4.1, without copying the base manifests. What is the Kustomize way?mediumKubernetes5 XP	Kubernetes	New	medium	5
Taints and TolerationsA node has the taint gpu=true:NoSchedule. A Pod has a matching toleration but no node selector or affinity. Which is true?hardKubernetes8 XP	Kubernetes	New	hard	8
HPA, VPA and Cluster AutoscalerDuring a traffic spike, the HorizontalPodAutoscaler scales api from 4 to 20 replicas, but 6 new Pods stay Pending with 0/5 nodes are available: Insufficient cpumediumKubernetes5 XP	Kubernetes	New	medium	5
Well-Architected PillarsDuring a Well-Architected review, the team discusses deploying across multiple Availability Zones, testing recovery procedures, and having the system automaticaeasyCloud3 XP	Cloud	New	easy	3
Shield vs WAF vs GuardDutyA web app behind an Application Load Balancer is receiving requests with SQL injection payloads in the query string. You want to block these requests before themediumCloud5 XP	Cloud	New	medium	5
Using Module OutputsThe root module calls a child module with module "network" { source = "./modules/network" }. Inside it, the VPC is awsvpc.main. How does the root module get theeasyTerraform3 XP	Terraform	New	easy	3
Variables and OutputsIn a reusable Terraform module, how do callers pass values in, and how does the module expose values out?easyTerraform3 XP	Terraform	New	easy	3