RDS SQL Server Serverless instances automatically scale computing resources based on workload demand, reducing costs and eliminating manual capacity planning.
You can also join the RDS Serverless DingTalk user group (Group ID: 41925003105) for consultation, communication, and feedback.
To ensure product stability and user experience, Alibaba Cloud will discontinue the sale of RDS for SQL Server serverless instances on November 3, 2025, and will stop providing related technical support on June 1, 2026. This includes, but is not limited to, new feature iterations and technical issue fixes. To ensure your product experience, convert your RDS for SQL Server serverless instances to pay-as-you-go instances as soon as possible.
Official launch
Serverless RDS instances will end their public preview from March 19, 2023 and will be officially launched on March 20, 2023. You can create a serverless RDS instance in the ApsaraDB RDS console.
-
Serverless RDS instances are available in the following regions: China (Shanghai), China (Hangzhou), China (Beijing), China (Zhangjiakou), China (Shenzhen), and China (Chengdu).
-
You can create a serverless RDS High-availability Edition instance that runs SQL Server 2016 Standard Edition, 2017 Standard Edition, or 2019 Standard Edition.
-
If you use a RAM user to create a serverless RDS instance, the AliyunRDSFullAccess policy must be attached to the RAM user. For more information, see Use RAM for resource authorization.
-
Service level agreement (SLA) commitments are not applicable to your serverless RDS instance or to the availability and liability of any relevant services. Alibaba Cloud shall not be liable for the adverse impacts of your use of serverless RDS instances and relevant services.
Overview
RDS SQL Server Serverless instances automatically scale computing resources with workload changes, optimizing costs and responsiveness.
The following figure compares resource utilization between a regular instance and a serverless instance under a fluctuating workload.
For a fluctuating workload:
-
Regular instance: Wastes resources during off-peak hours and lacks capacity during peak hours, affecting performance.
-
Serverless instance:
-
Scales resources with workload changes, minimizing idle capacity and reducing costs.
-
Matches peak-hour demand to maintain service stability.
-
Charges based on actual resource usage instead of fixed pricing, significantly reducing costs.
-
Eliminates manual configuration changes, improving O&M efficiency.
-
Optimized for high-throughput writes and high-concurrency workloads with elastic scaling for peak-and-trough access patterns.
-
Architecture
Benefits
-
Lower costs: No infrastructure management required. Instances are ready to use after creation and charge only for consumed resources.
-
Automatic elastic scaling: Computing resources scale automatically without manual scheduling, reducing O&M costs and risks.
-
Fully managed: Alibaba Cloud handles all O&M tasks, including upgrades, deployment, scaling, and alerts, ensuring continuous availability.
-
High availability: Built on a high-availability architecture.
Limits
-
Compared with regular RDS for SQL Server instances, RDS for SQL Server serverless instances do not support changing the time zone or character set, connecting to a self-managed domain, configuring Transparent Data Encryption (TDE), configuring Secure Sockets Layer (SSL) encryption, enabling disk encryption, upgrading the major engine version, or updating the minor engine version.
-
Serverless instances use the pay-as-you-go billing method. However, because they are sold based on RDS Capacity Units (RCUs), you cannot change the billing method of a serverless instance to subscription.
-
Serverless instances do not support the creation of read-only instances. To use read-only instances, create a primary instance with RDS Cluster Edition and then create read-only instances for it. Create an RDS for SQL Server instance and Overview of read-only RDS for SQL Server instances.
-
You cannot create database accounts with system administrator (SA) permissions or host accounts on a serverless instance. For more information, see Accounts and permissions.
Billing
For more information, see Serverless billing.
Use cases
-
Development and testing environments with fluctuating workloads.
-
SaaS applications, such as website building for small and medium-sized enterprises.
-
Educational use, such as teaching and student experiments.
-
IoT and edge computing with unpredictable workloads.
-
Fluctuating or unpredictable workloads.
-
Intermittent scheduled tasks.
-
Individual developers.
Get started
-
Adjust the RCU scaling range as needed. The instance automatically scales RCUs up or down within this range based on workload. Change the scaling range of RCUs.
-
Expand storage capacity manually when your storage needs increase.