How long does it take to migrate a SQL Azure server from one subscription to another?

Question

Hi
We've migrated all our apps to a new subscription but haven't done the databases yet to minimise disruption to users.

Can anyone help me to understand . . .

1. How long does it take for a database migration to another subscription?
2. Will the databases be offline during the migration?

thanks

Answer 1

When you move Azure SQL server, there will not be any downtime. See the below from the documentation.

"For example, if you move an Azure SQL logical server, its databases and other dependent resources to a new resource group or subscription, applications that use the databases experience no downtime. They can still read and write to the databases. The lock can last for a maximum of four hours, but most moves complete in much less time."

Refer: https://learn.microsoft.com/en-us/azure/azure-resource-manager/management/move-resource-group-and-subscription

Hope this helps

Answer 2

The validation phase prior to the migration start takes 1-2 minutes. The migration succeeds almost inmediately in less than 15 seconds (East US).

At all times the database a 2 GB database was online. I did not have to update firewall rules,

Answer 3

Hi @MarkP Thank you for your question and for using Azure services.

**How long does it take for a database migration to another subscription? **
It doesn't matter whether you are migrating from one subscription to another or one region to another. It is the same concept as any other database migration except that within Azure, the migration will use the Azure backbone for networking bandwidth which will usually have better bandwidth compared to on-premises-to-Azure bandwidth. I would recommend testing to estimate the time as it can depend on the size of the database backups and the target data ingestion / restore throughput.

**Will the databases be offline during the migration? **
If you use migration tools like DMS or Azure Data Studio migration extension, you can migrate either in an online or offline method. Online method is for those scenarios that cannot afford the database to be offline for a long time.

Hope that helps

Regards,
Oury