This topic describes how to configure Transparent Data Encryption (TDE) for an ApsaraDB RDS for SQL Server instance. TDE can perform real-time I/O encryption and decryption on data files. Data is encrypted before it is written to a disk and is decrypted when it is read from a disk and written to the memory. After TDE is enabled for your RDS instance, the size of data files in the instance does not increase. You can use TDE without the need to modify the configurations of your application.
Prerequisites
- The RDS instance must run one of the following database engine versions:
- SQL Server 2019 SE
- SQL Server EE
- Your RDS instance belongs to the general-purpose instance family or the dedicated instance family.
- Your RDS instance is not a read-only instance. For more information, see Create a read-only ApsaraDB RDS for SQL Server instance.
- If you want to use Bring Your Own Keys (BYOKs), the certificate, private key, and password that are used for encryption and decryption are obtained.
Usage notes
- TDE cannot be disabled after it is enabled for an RDS instance. TDE can be enabled or disabled for a database based on your business requirements.
- If you use Key Management Service (KMS) to generate a key after you enable TDE for
an RDS instance, you must disable TDE for the RDS instance before you restore the
data of the RDS instance to a self-managed database. For more information, see Disable TDE.
Note After you disable TDE, some transaction logs are still encrypted. The backup files that are downloaded cannot be used to restore the data of the RDS instance. In this case, wait until three log backups and one full backup are complete on the RDS instance. Then, download the most recent full backup file that is generated. This full backup file contains the decrypted data of the RDS instance. For more information, see Database Encryption in SQL Server 2008 Enterprise Edition. For more information about how to configure a backup policy, see Back up an ApsaraDB RDS for SQL Server instance.
- After you enable TDE for an RDS instance, the CPU utilization of the RDS instance significantly increases.
Enable TDE
Disable TDE
After TDE is enabled for an RDS instance, TDE cannot be disabled. To disable TDE for a database, you can remove the database from the Selected Databases section.
- Access RDS Instances, select a region at the top, and then click the ID of the target RDS instance.
- In the left-side navigation pane, click Data Security.
- Click the TDE tab. Then, click TDE Settings.
- Select databases from the Selected Databases section, click the
icon to move the selected databases to the Unselected Databases section, and then click OK.