Can I decrease the disk space from a SQL Managed Instance

Question

I have a SQL Managed Instance that is currently using 7TB of disk space, I need to temporarily increase disk space to 8TB, after I'm done using that extra space, can I downscale disk size without changing the vCPU settings?

Does any of the changes require a downtime?

Answer 1

Hello SÉRGIO RICARDO LESSA JUNIOR, you can absolutely bump your Azure SQL Managed Instance up from 7 TB to 8 TB of storage and then drop it back down to 7 TB (or whatever size you actually need) without touching the vCPU count. Here’s how it works:

Increase storage only

• In the Azure portal go to your SQL Managed Instance → Compute + storage → move the storage slider to 8 TB → Apply.
  • Or run the CLI/PowerShell command to update only the storage property (no need to touch --vcores).
  Use the extra space for your workload Decrease storage only
  • Once you’re done, make sure your actual data usage is ≤ your target (in your case ≥ 7 TB).
  • Go back to Compute + storage and slide back to 7 TB (or via CLI/PowerShell again).

Important notes on downtime:

• But if you only change the storage size, there is no service restart or node failover—storage-only updates are online and won’t cause downtime.
• Just be sure you never go below the actual used space (you can’t shrink below what’s allocated to your databases).

https://learn.microsoft.com/en-us/azure/azure-sql/database/single-database-scale?view=azuresql&source=recommendations&tabs=azure-portal
https://learn.microsoft.com/en-us/azure/azure-sql/managed-instance/service-tiers-managed-instance-vcore?view=azuresql&tabs=azure-powershell
https://learn.microsoft.com/en-us/azure/azure-sql/managed-instance/file-space-manage?view=azuresql-mi