Learn the vocabulary of persistent disk storage attached to ephemeral cloud containers.
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At standup, a dev mentions attaching persistent disk storage to a container so its data survives even after the container restarts. What is this feature called?
A persistent volume attaches durable disk storage to a container that survives restarts, redeployments, and even the container being recreated, unlike the container's own ephemeral filesystem which resets each time. This is essential for any workload that needs to retain data, like a database, across the container's lifecycle. Without a persistent volume, a container's local disk state is treated as fully disposable.
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During a design review, the team wants a volume to be tied to a specific physical region so the attached compute instance must run close to where the data actually lives. Which concept explains this constraint?
Volume-to-region data locality means a persistent volume physically exists in a specific region, so the compute instance using it generally must run in that same region to access the storage efficiently, or often at all. This constraint is a meaningful architectural consideration when designing a globally distributed application, since it limits where a stateful workload can actually run. Stateless workloads without an attached volume don't face this same regional pinning.
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In a code review, a dev configures a scheduled process to copy a volume's contents to external storage on a recurring basis. What does this represent?
Automated volume backup copies a persistent volume's data to external storage on a recurring schedule, protecting against data loss if the primary volume becomes corrupted or is accidentally deleted. Relying solely on the primary volume with no separate backup means a single failure point could result in permanent data loss. This backup practice is standard for any workload storing data the team can't afford to lose.
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An incident report shows an application was redeployed and its uploaded files disappeared because they had been written to the container's local filesystem instead of the attached volume. What practice would prevent this?
Ensuring the application writes persistent data to the specific mounted volume path, rather than an arbitrary location on the container's own ephemeral filesystem, is what actually makes that data survive a redeployment. Assuming the container's local filesystem persists on its own is a common misconception that leads to exactly this kind of silent data loss. Configuring the application correctly to target the volume mount point is a necessary setup step, not something that happens automatically just because a volume exists.
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During a PR review, a teammate asks why the team attaches a persistent volume to a database container instead of relying on the container's default ephemeral storage. What is the reasoning?
A container's default ephemeral filesystem is wiped clean whenever the container restarts or is recreated, which would mean losing all database data on every routine redeployment. A persistent volume exists independently of the container's own lifecycle, so the data survives exactly the kind of restart that would otherwise destroy it. This durability is a fundamental requirement for any stateful workload like a database.