Azure Storage is a massively scalable, durable cloud storage service. A single Storage Account provides access to several types of storage — blobs, files, queues, and tables — all within the same account.
Storage Account Types
- Standard general-purpose v2 (GPv2): Supports Blob, File, Queue, Table. The recommended default for most scenarios.
- Premium Block Blobs: SSD-backed, for high transaction rates and low-latency blob workloads.
- Premium File Shares: SSD-backed Azure Files for latency-sensitive SMB/NFS workloads.
- Premium Page Blobs: For VM OS disks (Azure Disk Storage).
Azure Blob Storage
Blob Storage is Azure's object storage service for unstructured data. Blobs are organised in containers (similar to GCP buckets or AWS S3 buckets). Use cases: images, videos, logs, backups, static websites.
Three blob types:
- Block blobs: Optimised for uploading large objects. The standard choice for most data.
- Append blobs: Optimised for append operations. Best for logging.
- Page blobs: Optimised for random read/write. Used by Azure VM disks.
Blob Access Tiers
| Tier | Access Frequency | Storage Cost | Retrieval Cost |
|---|---|---|---|
| Hot | Frequently accessed | Highest | Lowest |
| Cool | Infrequently (once/month) | Lower | Low (30-day min) |
| Cold | Rarely (once/quarter) | Lower still | Medium (90-day min) |
| Archive | Rarely (once/year) | Lowest | Highest (180-day min, hours to rehydrate) |
Lifecycle Management Policies automatically transition blobs between tiers or delete them after a specified number of days — reducing manual cost management.
Azure Files
Azure Files provides fully managed cloud file shares accessible over the SMB (Windows) and NFS (Linux) protocols. Files can be mounted simultaneously on Windows, Linux, and macOS — both on-premises and in Azure.
Use cases:
- Replace on-premises NAS/file servers
- Shared configuration files for multiple VMs
- Lift-and-shift applications that expect a file system interface
Azure Disk Storage
Azure Disk Storage provides block-level storage volumes (similar to Persistent Disk in GCP). Types:
| Type | Max IOPS | Best For |
|---|---|---|
| Ultra Disk | 160,000 | Most demanding databases, SAP HANA |
| Premium SSD v2 | 80,000 | Latency-sensitive databases |
| Premium SSD | 20,000 | Production VMs and databases |
| Standard SSD | 6,000 | Web servers, dev/test |
| Standard HDD | 2,000 | Backups, archival |
Redundancy Options
| Option | Copies | Locations |
|---|---|---|
| LRS (Locally Redundant Storage) | 3 | Single data centre |
| ZRS (Zone-Redundant Storage) | 3 | 3 AZs in one region |
| GRS (Geo-Redundant Storage) | 6 | Primary + paired region (LRS each) |
| GZRS (Geo-Zone-Redundant Storage) | 6 | 3 AZs in primary + LRS in paired region |
For critical data, use GRS or GZRS and enable Read-access GRS (RA-GRS) to allow reading from the secondary region even during primary outages.