Azure SQL DTU to vCore Migration Steps for PAAS Databases on Cloud

In this article, we are going to talk about Azure SQL DTU to vCore Migration. I have already spoken about the advantages of moving to a vCore based pricing model on a different article. Generally, for customers who are just starting up with their online business, a DTU based deployment is the most cost-effective solution.

Azure SQL Hyperscale Tier

Over time, your application might need additional performance, and DTU models might not be sustainable. As a refresher, here is the calculation for vCores vs DTUs:

1 vCore of General Purpose = 100 DTUs Standard
1 vCore of Business Critical = 125 DTUs Premium
80 vCores = 8000 DTUs **

** A maximum of 4000 DTUs are support at the time of writing this article.

Why move to vCore models?

Transparent pricing for the virtual cores and memory that you use.
Low latency disk sub-system is offering excellent throughput for high-transactional tables.
Dedicated page writing server, offering low latency of 0.25 ms – 2.5 ms of response times
Dedicated NVMe Ultra SSD’s helps to achieve low-latency high-performance workloads
Hyperscale workloads depend on a dedicated log service to manage DMLs (Insert-Update & Deletes)

Restrictions

Moving to “Hyperscale Tier” is a one-way process, which means no going back.
TDE or “Transparent Data Encryption” is not supported (Hyperscale)
“Bulk logged” recovery model is not supported. (Hyperscale)
Point in item backup restores are not supported (Hyperscale)
Managed instances are not supported on a hyperscale tier.
In-memory OLTP objects cannot be migrated
CDT is not supported

Azure SQL DTU to vCore Migration Steps:

Migrating from SQL DTU based model to vCore is thankfully straightforward. The migration is in place and does not need a lot of downtimes. Moreover, the existing Azure SQL (logical server) can still host the databases under the vCore licensing mode. This means that there are no changes to the current connection string and no application changes are required.

What does change is the pricing tier and the fact that the “Hyperscale” does not allow you to come back to the DTU based service tier. With this in mind, follow the simple steps below to complete it:

Go to your Azure SQL Logical Server and select your Database.
Under the “Overview” menu on the left, click on the “Pricing Tier” hyperlink.
Select the service tier that you want to move to under the vCore pricing model.

That’s it! it takes less than a minute to complete the migration and you should be up and running shortly after. Here are some screenshots below for your reference:

Conclusion

As you can see from the example explained above, migration is easy and can be done anytime when you want to switch. Once you are fully aware of the performance benefits, we recommend going for it.

We hope our article was helpful with your Azure SQL DTU to vCore Migration plan. Your valuable feedback and suggestions are welcome in the comment box down below. Thanks for visiting!