# Knowledge Check: Storage Fundamentals

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**1. Two containers in the same Pod need to share files with each other, but nothing needs to
survive the Pod being replaced. What's the simplest correct choice?**

*Answer:* `emptyDir` — shared within the Pod, deliberately temporary, exactly matching the
requirement. Reaching for a PV/PVC here would be more machinery than the problem needs.

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**2. A Pod using a PVC is deleted and a new Pod is created referencing the SAME PVC. What
happens to the data?**

*Answer:* It's preserved. The PVC and its bound PV exist independently of any specific Pod — the
new Pod picks up exactly where the data was left, which is the entire reason to use persistent
storage instead of `emptyDir` for anything that needs to outlive a single Pod's lifetime.

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**3. True or false: a Pod's manifest must specify exactly which PersistentVolume backs its
storage request.**

*Answer:* False. A Pod references a PVC (a request), not a PV directly — the binding between
PVC and an actual PV is resolved separately, which is exactly the indirection that lets the same
Pod manifest work regardless of which physical storage ends up behind it.

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**4. What does a StorageClass's reclaim policy actually control, and why would a team choose
`Retain` over `Delete` for a production database's storage?**

*Answer:* It controls what happens to the underlying storage after its PVC is deleted. `Retain`
keeps the data around for manual recovery instead of immediately destroying it — a safety
margin against an accidental `kubectl delete pvc` on something genuinely important, at the cost
of needing manual cleanup later.

## Instructor Notes

**Facilitation:** Question 2 is worth confirming lands correctly — it's the single fact that
justifies the entire PV/PVC indirection existing at all.

**Approximate timing:** 5 minutes.