1.3 - Cloud storage and database types
Cloud+ CV0-004 objective 1.3 covers cloud storage and database services. Object storage keeps unstructured data as objects with metadata, accessed over HTTP, and scales massively - ideal for backups, media and static content. Block and file storage suit VMs and shared file systems respectively. Storage tiers trade cost for access speed: an archive tier is cheapest for rarely accessed data you can wait minutes or hours to retrieve, while hot tiers cost more for instant access. A managed relational database offloads tasks like patching the DB engine and backups from the customer. A write-behind cache acknowledges the client immediately and defers writes, which risks data loss on failure. Expect scenario questions that describe a data type, access pattern, cost goal or managed offload and ask which storage type, tier or database option fits.
Unstructured objects + metadata over HTTP = object storage. Cheapest, slow retrieval = archive tier. Managed DB = provider patches the engine + backups. Write-behind cache = fast acks but risk of data loss on failure.
Practice questions
1. Which storage type keeps unstructured data as objects with metadata, accessed over an HTTP API?
- Block storage
- File storage
- Object storage (correct answer)
- Ephemeral disk
Object storage (e.g., S3) stores objects + metadata and is reached by HTTP/REST. Block storage attaches as a raw volume; file storage uses a shared filesystem.
2. Which storage type presents raw volumes to a VM that the OS formats with its own filesystem?
- Block storage (correct answer)
- Object storage
- File storage
- Archive storage
Block storage exposes raw volumes; the guest OS formats and mounts them, giving low latency for databases and boot disks. Object storage uses an HTTP API instead.
3. A queue lets a producer keep working while consumers process messages later. This pattern mainly provides:
- Stronger encryption
- Loose coupling (correct answer)
- Higher precision
- Shorter TTL
A message queue decouples producers from consumers so each scales and fails independently, smoothing spikes. It does not by itself add encryption or precision.
4. A globally distributed set of edge caches that serves content from the location nearest each user is a:
- Load balancer
- CDN (correct answer)
- VPN gateway
- Message bus
A CDN (content delivery network) caches static assets at edge locations near users, cutting latency and origin load. A load balancer only spreads traffic across backends.
5. Which storage type is best for a shared filesystem mounted by many VMs over SMB or NFS?
- Object storage
- File storage (correct answer)
- Block storage
- Cold archive
File storage exposes a shared filesystem over SMB or NFS that multiple clients mount concurrently. Block storage is usually attached to one instance; object storage uses HTTP.
6. Which storage tier is cheapest per GB but has retrieval delays, suiting rarely accessed archives?
- Hot object tier
- Standard block
- Cold archive tier (correct answer)
- In-memory cache
A cold archive tier stores rarely used data at the lowest cost but with retrieval latency of minutes to hours. Hot tiers cost more per GB but return data instantly.