RDS for SQL Server Constraints

RDS for SQL Server only supports DB instances under the License Included model and does not support "bring your own license" (BYOL). After a DB instance is created, it contains the Microsoft SQL Server software license.

To ensure data security, there are certain constraints on using .

RDS for SQL Server DB instances are classified into three types: single, primary/standby, and cluster. Different types support different functions.

Naming

**Table 1** Naming
Item	Constraints
Instance name	4 to 64 characters long Must start with a letter. Only letters (case sensitive), digits, hyphens (-), and underscores (_) are allowed.
Database name	1 to 64 characters long Only letters, digits, hyphens (-), underscores (_), and periods (.) are allowed. It cannot start or end with an RDS for SQL Server system database name. RDS for SQL Server system databases include master, msdb, model, tempdb, resource, rdsdistribution, and rdsadmin. Databases cannot be created for a DB instance that is being restored or whose instance class is being changed. Databases with HA relationships can be renamed only after the replication relationships are removed.
Account name	1 to 128 characters long Only letters, digits, hyphens (-), and underscores (_) are allowed. It must be different from system accounts. System accounts include rdsadmin, rdsuser, rdsbackup, and rdsmirror.
Backup name	4 to 64 characters long Must start with a letter. Only letters (case sensitive), digits, hyphens (-), and underscores (_) are allowed.
Parameter template name	1 to 64 characters long Only letters (case sensitive), digits, hyphens (-), underscores (_), and periods (.) are allowed.

Security

**Table 2** Security
Item	Constraints
rdsuser roles	The administrator account of RDS for SQL Server is rdsuser, which has roles processadmin, public, and dbcreator but does not have the following roles: bulkadmin diskadmin securityadmin serveradmin sysadmin
rdsuser password	8 to 32 characters long Must contain at least three types of the following characters: uppercase letters, lowercase letters, digits, and special characters (~!@#$%^*-_=+?,).
Database port	RDS for SQL Server instances can use port 1433 (default) or ports 2100 to 9500 (excluding 5355 and 5985). For RDS for SQL Server 2017 and 2019 Enterprise, Standard, and Web editions, ports 5050, 5353, and 5986 cannot be used, either.
Disk encryption	If you enable disk encryption during instance creation, the disk encryption status and the key cannot be changed later.
VPC	The VPC where a DB instance is located cannot be changed after the instance is created.
Security group	By default, you can create a maximum of 100 security groups in your cloud account. By default, you can add up to 50 security group rules to a security group. One RDS DB instance can be associated with multiple security groups, and one security group can be associated with multiple RDS DB instances. When creating a DB instance, you can select multiple security groups. For better network performance, you are advised to select no more than five security groups.
System account	To provide O&M services, the system automatically creates system accounts when you create RDS for SQL Server DB instances. These system accounts are unavailable to you. rdsadmin: an account that has the sysadmin role and is used to query DB instance information, monitor instance status, rectify faults, migrate data, and restore data. rdsmirror: a primary/standby replication account, used to create mirroring endpoints. rdsbackup: a backup account, used for backend backup. Mike: a Windows system account of RDS for SQL Server. It is used to initialize SQL statements during the DB instance initialization, including creating the rdsadmin database and related accounts.
Instance parameter	To ensure the optimal performance of RDS, you can modify parameters in the parameter template you created as needed.

Instance Operations

**Table 3** Instance operations
Item	Constraints
Instance deployment	ECSs where DB instances are deployed are not directly visible to you. You can only access the DB instances through IP addresses and database ports.
High CPU usage	If the CPU usage is high or close to 100%, data read/write and database access will become slow, and an error will be reported during data deletion.
Rebooting a DB instance	DB instances cannot be rebooted through commands. They must be rebooted through the RDS console.
Stopping or starting a DB instance	You can temporarily stop pay-per-use instances to save money. After stopping your instance, you can restart it to begin using it again.
Viewing backups	You can download backups for local storage. To download a backup, you can use OBS Browser+ or the download URL.
Log management	RDS for SQL Server logging is enabled by default and cannot be disabled.
Recycle bin	RDS allows you to move deleted pay-per-use DB instances to the recycle bin. You can rebuild a DB instance that was deleted up to 7 days ago from the recycle bin.

Functions

**Table 4** Functions
Item	Single	Primary/Standby	Cluster
Maximum number of databases	100	100	100
Number of database accounts	Unlimited	Unlimited	Unlimited
Creation of user, LOGIN, or database	Supported	Supported	Supported
Database-level DDL trigger	Supported	Supported	Supported
Database permission authorization	Supported	Supported	Supported
KILL permission	Supported	Supported	Supported
SQL Profiler	Supported	Supported	Supported
Tuning Adviser	Supported	Supported	Supported
Change Data Capture (CDC)	Supported	Supported	Supported
Change tracking	Supported	Supported	Supported
Windows domain account login	Supported	Supported	Supported
SQL Server Integration Services (SSIS)	Not supported	Not supported	Not supported
SQL Server Analysis Services (SSAS)	Not supported	Not supported	Not supported
R Services	Not supported	Not supported	Not supported
Asynchronous communication	Not supported	Not supported	Not supported
Policy management	Not supported	Not supported	Not supported
Private domain name	Supported	Supported	Supported
SQL Agent job	Supported	Supported	Supported