Focused, hands-on DevOps and server-side problems with hints, feedback, and automated solution checks.
Build five ways to combine containers in one Pod: a sidecar that extends the app, an init container that finishes before the app starts, a native sidecar with a startup guarantee, an ambassador that mutates an outbound call, and an adapter that translates an inbound one.
Build a StatefulSet with a headless Service, watch ordered Pod creation, verify per-replica PVC naming, scale down and back up, prove stable identity, then roll an image update and roll back using ControllerRevision history.
Run one Pod per node with a DaemonSet, roll an image update, roll back to the previous revision, and restrict coverage to a subset of nodes with a nodeSelector.
Build a ReplicaSet by hand, observe self-healing, then update its template and end up with Pods running different images. Layer a Deployment on top and confirm the full ownership chain.
Build a Pod from scratch, exec into it, try to edit an immutable field, explore all three restart policies, and observe graceful termination.
Observe the Delete and Retain reclaim policies in action, recover a Released PV by patching claimRef, and recover data by creating a new PV pointing to the same storage directory.
Explore how the DefaultStorageClass admission controller injects storage classes, explicitly name a StorageClass, switch the cluster default, and inspect where local-path stores volumes on the node.
Learn the three static PV binding patterns - generic match, label selector, and bidirectional claimRef - then use a no-provisioner StorageClass with WaitForFirstConsumer to pin storage to a specific node.
Use emptyDir volumes to share data between containers, understand the volume lifecycle across container restarts and pod deletion, and explore memory-backed ephemeral storage.
Create a CronJob, trigger Jobs manually, limit job history, suspend the schedule, and observe all three concurrencyPolicy modes: Allow, Forbid, and Replace.
