Manage Disks¶
Managing disks in Azure allows you to expand storage capacity or improve performance throughput. These operations can often be performed on running VMs with minimal disruption.
Disk Operation Matrix¶
| Operation | Downtime Required | CLI Command Example |
|---|---|---|
| Attach Data Disk | No | az vm disk attach |
| Detach Data Disk | Recommended | az vm disk detach |
| Expand Size | Usually no (online resize supported for most managed disks) | az disk update --size-gb 1024 |
| Change Tier | Yes (Stop/Deallocate) | az disk update --sku Premium_LRS |
Disk Management Workflow¶
graph TD
A[Identify Disk Need] --> B{Operation Type}
B -->|New Storage| C[Attach Managed Disk]
B -->|More Space| D[Resize Disk Online or Deallocate]
B -->|Better Perf| E[Stop VM/Deallocate]
D --> F[Resize in Portal/CLI]
E --> G[Update SKU: Std to Prem]
F --> H[Extend File System in OS]
C --> H
H --> I[Operation Complete]Warning
Decreasing the size of an Azure disk is NOT supported. You must create a new smaller disk and migrate data.
Note
Enable Encryption at Host to encrypt temp disk and disk caches.