undefined labs - 20 hands-on challenges
Solve 20 real undefined challenges in an isolated container in your browser. No setup, no fake shells.
- Debug a CrashLooping Pod - beginner · Use Pod events and logs to recover a broken workload.
- Repair Namespace Scoping - beginner · Place a team workload in its intended namespace.
- Correct Workload Labels - beginner · Repair metadata so an operational label query returns the full production fleet.
- Recover a Failed Job - beginner · Repair a one-shot batch workload and its restart policy.
- Right-Size a Worker Pod - beginner · Resolve scheduling pressure and an OOMKilled container.
- Repair Service Discovery - intermediate · Restore traffic between a frontend and its backend Service.
- Fix Projected Configuration - intermediate · Correct ConfigMap and Secret projections in an application Pod.
- Separate Liveness and Readiness - intermediate · Restore storefront endpoints by assigning health probes their correct roles.
- Recover the Database Pool - intermediate · Unblock PgBouncer initialization and point its pool at PostgreSQL.
- Debug a Redis Sidecar Pod - intermediate · Inspect per-container logs and repair a cache/exporter pair.
- Enforce Least-Privilege RBAC - advanced · Replace wildcard access with the exact permissions an auditor needs.
- Recover a Rollout and HPA - advanced · Fix scheduling and readiness, then scale a Deployment under load.
- Restore the Storefront Gateway - advanced · Repair Kong declarative routing and cross-namespace network policy.
- Restore Redis Stateful Identity - advanced · Recover stable ordinals, headless discovery, and a safe cache policy.
- Make Maintenance Disruption-Safe - advanced · Repair dedicated-node placement and a PodDisruptionBudget before a drain.
- Stop Overlapping CronJobs - beginner · Control missed schedules, concurrency, and Job history.
- Harden a Pod Security Context - beginner · Bring a privileged workload up to the Restricted security standard.
- Bind a Pending PVC - intermediate · Match storage class and access modes to available persistent storage.
- Repair cert-manager TLS Issuance - intermediate · Fix issuer scope and the TLS Secret contract for a Certificate.
- Recover Kafka Replication and Consumption - advanced · Restore ISR health, right-size brokers, and prove produce/consume through a real Kafka protocol endpoint.