💾 Cloud Storage 101: From Blobs to Disks, and Everything in Between

Welcome back, data wrangler!
Last week, we mapped out the roads of the cloud with Azure Networking. This week in “Back to the cloud”, we’re landing on a vital destination: Azure Storage.

✅ 1. Core Azure Storage Services

🔷 2. Azure Blob Storage (Most Tested)

• Stores unstructured data (images, videos, logs, backups, big data).

• Access via HTTP/HTTPS, REST API, SDKs.

• Supports tiers for cost management:

  • Hot: Frequently accessed (higher cost).

  • Cool: Infrequently accessed (cheaper storage, higher access cost).

  • Archive: Rarely accessed (very cheap, high latency to retrieve).

📌 Blob Types:

• Block blob: Large files, binary data (e.g., videos, documents)

• Append blob: Ideal for logs

• Page blob: Used for Azure VM disks

📁 3. Azure File Storage

• Fully managed shared file system in the cloud.

• Access via SMB or NFS protocols (mountable on Windows, Linux, macOS).

• Azure File Sync lets you cache Azure Files on on-prem servers (hybrid scenario).

📌 Use when you need:

• Traditional file shares

• Cloud backup for on-prem file servers

• Centralized storage accessible by many VMs

💽 4. Azure Disk Storage

• Provides persistent block-level storage for Azure VMs.

• Types:

  • OS Disk – VM boot volume

  • Data Disk – Additional attached storage

• Performance Tiers:

  • Standard HDD: Low-cost, low-performance

  • Standard SSD: Better performance, still low-cost

  • Premium SSD: High-performance workloads (databases, production)

  • Ultra Disk: Extreme performance (high IOPS), very expensive

📌 Attached only to VMs.

📨 5. Azure Queue Storage

• Stores messages for reliable communication between services.

• Supports millions of messages, up to 64KB each.

• Used in asynchronous messaging scenarios (like microservices).

📌 Use to decouple app components and ensure resilient workflows.

🔑 6. Azure Table Storage

• NoSQL key-value store for structured, non-relational data.

• Fast, cheap, and simple.

• Use for:

  • Storing metadata

  • App settings

  • Sensor or IoT data

📌 Schema-less, highly scalable, and lower-cost than traditional databases.

💾 7. Storage Account Types

📌 Always prefer GPv2 unless there's a specific performance need.

🔐 8. Security & Access Control

• Encryption at rest by default (using Azure-managed keys or customer-managed keys).

• Supports HTTPS for secure data transfer.

• Shared Access Signature (SAS): Grants limited-time, scoped access to storage resources.

• Azure AD integration for identity-based access control (e.g., RBAC).

• Private Endpoints: Secure access to storage over VNet (no public IP).

🧪 9. High Availability & Redundancy Options

📌 Choose ZRS or GRS for critical data. LRS is cheapest but least resilient.

💰 10. Storage Pricing Model

• Based on:

  • Type of storage (Blob, File, etc.)

  • Storage tier (Hot, Cool, Archive)

  • Operations (read/write/delete)

  • Data transfer (egress)

📌 Hot = expensive to store, cheap to access 📌 Archive = cheap to store, expensive to access

⚙️ 11. Management Tools

• Azure Portal: GUI-based management.

• Azure Storage Explorer: Desktop tool to manage blobs, files, queues.

• Azure CLI / PowerShell: For scripted management.

• ARM Templates / Bicep: For infrastructure as code.

✅ AZ-900 Key Storage Use Cases (Match the Service)

🧠 Final Exam Tips for Azure Storage (AZ-900)

• Know Blob tiers (Hot, Cool, Archive) and their tradeoffs.

• Understand redundancy levels: LRS vs ZRS vs GRS.

• Know what storage type fits what scenario.

• Know what Shared Access Signature (SAS) is for.