World K4: Notes, Lockers & Packages

Lockers: PV and PVC

You will learn: to ask for storage with a PVC, so data outlives the pod that wrote it.

Checked with Kubernetes 1.37 on 31 Oct 2026

The problem

You are here: cluster kind-dev namespace default

~/shop $ kubectl exec cashier -- sh -c 'echo nasi lemak x2 >> /tmp/orders.txt'~/shop $ kubectl delete pod cashierpod "cashier" deleted from default namespace~/shop $ kubectl apply -f cashier.yamlpod/cashier created~/shop $ kubectl wait --for=condition=Ready pod/cashier --timeout=60spod/cashier condition met~/shop $ kubectl exec cashier -- cat /tmp/orders.txtcat: can't open '/tmp/orders.txt': No such file or directorycommand terminated with exit code 1

The cashier kept today’s orders inside its box. The pod was replaced. Every order is gone. You need a locker that stays.

Watch

Tap the line that says how big the locker is.

0 of 1 found

You fill in a locker request slip. That slip is a (PVC). It says how big, and how many may use it.

Predict

You apply the claim. kubectl get pvc says Pending. Why?

Try it

Apply the claim, then the cashier pod that uses it. Check the claim again.

You are here: cluster kind-dev namespace default

dev-control-planeOpenManager

No trays here.

dev-workerOpen

No trays here.

dev-worker2Open

No trays here.

Time: +0s (sped up)

Hint

cat cashier.yaml shows where the pod names the claim.

Watch

You are here: cluster kind-dev namespace default

~/shop $ kubectl get pvcNAME     STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   VOLUMEATTRIBUTESCLASS   AGEorders   Bound    pvc-14148d20-7191-41bd-b0ee-9b62e9454543   1Gi        RWO            standard       <unset>                 14s~/shop $ kubectl get pvNAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM            STORAGECLASS   VOLUMEATTRIBUTESCLASS   REASON   AGEpvc-14148d20-7191-41bd-b0ee-9b62e9454543   1Gi        RWO            Delete           Bound    default/orders   standard       <unset>                          14s

The slip is now Bound to a (PV): the real locker. Nobody built it by hand. The next lesson shows who did.

Try it

The cashier wrote an order into the locker. Replace the pod. Then read the orders.

You are here: cluster kind-dev namespace default

dev-control-planeOpenManager

No trays here.

dev-workerOpen

cashier

dev-worker2Open

No trays here.

Time: +0s (sped up)

Check

PV or PVC? Sort each one.

Drag a card into a box. Or tap the card, then tap the box.

You did it!

You can now keep data in a locker that outlives its pod.

Go deeper (optional)

Careful: kind’s standard class has reclaimPolicy: Delete. Delete the claim, and the PV and its data go too. Use Retain for data you must keep. While a pod uses the claim, deleting it waits. The claim shows Terminating until that pod is gone.

Real rep (optional), on a practice kind cluster:

Real mission

In the practice terminal above, cat claim.yaml and cashier.yaml. Save both on your machine.
Ask for a locker.
kubectl apply -f claim.yaml
Start the cashier.
kubectl apply -f cashier.yaml
Watch the slip turn Bound.
kubectl get pvc,pv
Write an order.
kubectl exec cashier -- sh -c 'echo teh tarik >> /data/orders.txt'
Tidy up. This deletes the data too.
kubectl delete -f cashier.yaml -f claim.yaml

0 of 6 steps done · Your ticks are saved.