A cloud architect is documenting the storage types used across an IaaS deployment. One tier presents raw block devices that are attached to a single virtual machine, formatted with a file system by the guest operating system, and used to run a relational database. Which storage type does this description identify?
- AObject storage, where each item is stored as a discrete object with metadata and retrieved over an HTTP-based API by its key
- BVolume storage, where a block device is attached to an instance and the guest operating system applies its own file system Correct
- CEphemeral storage, where the capacity is destroyed automatically the moment the instance is stopped or terminated
- DLong-term archival storage, which is optimised for infrequent access and low cost at the expense of retrieval latency
Why A is wrong: Object storage is tempting because it is the other headline cloud storage class, but it exposes items through an API by key rather than a raw block device that the guest OS formats and mounts, so it cannot host a file system for a database in this way.
Why B is correct: Correct: volume (block) storage presents a raw device to one instance, which the guest OS partitions and formats, making it the standard choice for databases and boot volumes in IaaS.
Why C is wrong: Ephemeral storage is also block-based and locally attached, which makes it tempting, but its defining trait is that data is lost when the instance stops, whereas the description implies persistent database storage.
Why D is wrong: Archival storage is a plausible distractor because it is a named cloud tier, but it targets cold, rarely read data and imposes retrieval delays, which is unsuitable for an actively running relational database.