Why Core Storage Matters
Azure provides multiple storage options — but choosing the right one depends on whether you need unstructured data storage, file shares, key-value stores, or messaging. Many exam questions test whether you can map a workload requirement to the correct storage type.
1. Blob Storage
Definition:
Object storage for unstructured data such as images, videos, backups, and logs.
Tiers:
-
Hot → frequently accessed data.
-
Cool → infrequently accessed data (30+ days).
-
Archive → rarely accessed, lowest cost, retrieval latency hours.
Features:
-
Blob snapshots (point-in-time recovery).
-
Lifecycle management (automatic tiering).
-
Secure with SAS tokens, RBAC, or private endpoints.
Use Cases:
-
Storing backups, images, media.
-
Hosting static websites.
-
Data lake for analytics (Azure Data Lake Storage Gen2).
2. File Storage
Definition:
Fully managed SMB protocol-based file shares in the cloud.
Features:
-
Lift-and-shift for legacy apps that expect a file share.
-
Supports Azure File Sync (cache in on-prem Windows servers).
-
Can integrate with on-prem Active Directory.
Use Cases:
-
Shared file storage for multiple VMs.
-
Replacing or extending on-prem file servers.
-
Hybrid storage with caching.
3. Table Storage
Definition:
NoSQL key-value store for semi-structured data.
Features:
-
Schema-less design.
-
Large scale and high availability.
-
Cost-effective compared to relational DBs.
Use Cases:
-
IoT telemetry data.
-
User profiles, metadata storage.
-
Semi-structured log data.
4. Queue Storage
Definition:
Simple messaging service for decoupling applications.
Features:
-
Stores millions of messages (up to 64 KB each).
-
Messages delivered via polling model.
-
Not as advanced as Service Bus (no topics, sessions).
Use Cases:
-
Workload distribution between front-end and background processors.
-
Reliable communication between app components.
-
Basic async task management.
Example Enterprise Scenario
A healthcare system needs:
-
Patient records stored securely (structured + encrypted).
-
Medical images stored long-term.
-
Hybrid file storage accessible by both on-prem and cloud VMs.
-
A way for the patient portal to queue tasks for processing.
Correct design:
-
Use SQL DB with TDE for structured records.
-
Use Blob Archive tier for medical images.
-
Deploy Azure Files + File Sync for hybrid file access.
-
Use Queue Storage for portal task distribution.
Confusion Buster
-
Blob vs File Storage
-
Blob = unstructured, object-based.
-
File = structured, SMB protocol for legacy apps.
-
-
Table vs Cosmos DB
-
Table = simple, cost-effective NoSQL.
-
Cosmos DB = advanced NoSQL with global distribution.
-
-
Queue vs Service Bus
-
Queue = basic messaging, polling model.
-
Service Bus = advanced messaging (topics, sessions, DLQ).
-
Exam Tips
-
“Which storage option for video archives?” → Blob Archive Tier.
-
“Which service replaces on-prem file servers?” → Azure Files.
-
“Which service provides schema-less key-value store?” → Table Storage.
-
“Which service decouples app components with simple messaging?” → Queue Storage.
What to Expect in the Exam
-
Direct Q: “Which Azure storage is best for unstructured backups?” → Blob.
-
Scenario Q: “Company needs hybrid file storage with on-prem sync.” → Azure Files + File Sync.
-
Scenario Q: “App must process millions of async messages.” → Queue Storage.
-
Trick Q: “Table Storage provides global multi-region distribution.” → False (Cosmos DB does).