Problems

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24 of 277 problems

Title	Topic	Acceptance	Difficulty	XP
Find Files by Name, Size and AgeSearch a directory tree for files matching a name, a minimum size and a recent modification time.easyLinux10 XP	Linux	New	easy	10
Fix "Permission denied" on Service DataA service account cannot write its own data directory. Find the real cause and fix it without loosening permissions.easyLinux10 XP	Linux	New	easy	10
Find Every Config That Uses a SettingSearch a whole configuration tree for files that still reference a deprecated hostname.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
Which Package Owns a FileOn a RHEL server you find /usr/bin/dig and want to know which installed package it came from. Which command answers that?easyLinux3 XP	Linux	New	easy	3
Count Matching Files RecursivelyWrite a script that counts matching files in any directory tree, handling odd file names and bad input.easyShell10 XP	Shell	New	easy	10
Search and Replace Across Many FilesUpgrade every http:// endpoint to https:// in all config files of a tree, and only in config files.easyShell10 XP	Shell	New	easy	10
Top Talkers in an Access LogBuild a pipeline that finds the busiest client IPs in a web server log and formats the report exactly.mediumShell20 XP	Shell	New	medium	20
Filenames with Spaces in PipelinesYou need to delete all .tmp files under a directory; some names contain spaces and newlines. Which command is safe?hardShell8 XP	Shell	New	hard	8
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
Fix a Deployment Stuck Pulling Its ImageA rollout is stuck with Pods in ImagePullBackOff. Find the broken image reference and get every replica running.easyKubernetes10 XP	Kubernetes	New	easy	10
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
Roll Back a Broken Helm UpgradeThe latest Helm upgrade broke a release. Find the last good revision in its history and roll back to it.mediumKubernetes20 XP	Kubernetes	New	medium	20
Remove Releases of a Deprecated ChartFind every release that still runs a deprecated chart version, in any namespace, and uninstall only those.easyKubernetes10 XP	Kubernetes	New	easy	10
Fix a Chart That Won't InstallA colleague's chart fails to install. Find what is wrong with it, fix the chart, and install it.mediumKubernetes20 XP	Kubernetes	New	medium	20
A Deployment That Creates No PodsA Deployment sits at zero Pods and there are no Pending Pods to describe. Find what blocks it and fix the Deployment.mediumKubernetes20 XP	Kubernetes	New	medium	20
The Policy That Lets Nothing InA NetworkPolicy should let the frontend reach the backend, yet every request times out. Find the mistake in the policy and fix it without opening anything else.mediumKubernetes20 XP	Kubernetes	New	medium	20
Unreachable from OutsideAn external health checker polls the app on a fixed port of every node and gets nothing. Find what is wrong with the Service and fix it.mediumKubernetes20 XP	Kubernetes	New	medium	20
The Ingress Returns 404 and 503The shop's Ingress serves nothing it should. Find what doesn't match between the Ingress, its class and the Services, and fix it.mediumKubernetes20 XP	Kubernetes	New	medium	20
The Route That Never AttachedAn HTTPRoute was applied without errors, but the Gateway ignores it. Find why it isn't attached or can't reach its backend, and fix it.hardKubernetes40 XP	Kubernetes	New	hard	40
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
An Upgrade Stuck in Its HookA Helm upgrade failed because its pre-upgrade hook timed out. Find the hook that never finished, then complete the upgrade the team wanted.mediumKubernetes20 XP	Kubernetes	New	medium	20
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
Sorting with kubectlYou need to find the Pod in namespace prod whose first container has restarted the most. Which command works?easyKubernetes3 XP	Kubernetes	New	easy	3