This topic provides answers to some frequently asked questions about the sandbox feature of Database Backup (DBS).
Overview
Fees and promotions
Point in time to which the data of a sandbox instance can be restored
Create a sandbox instance
Use of sandbox instances
How am I charged for the sandbox feature?
For more information, see DBS sandbox fees.
What is the time range to which the data of a sandbox instance can be restored?
The time range to which the data of a sandbox instance can be restored depends on whether the log backup feature is enabled for the source database instance. The log backup feature is also called the incremental backup feature.
If the log backup feature is enabled, you can restore the data to a point in time within the time range that starts when the most recent full backup set is created before the sandbox feature is enabled and ends when the last binary log file is created. You can restore the data to a point in time that is accurate to the second.
If the log backup feature is disabled, you can restore the data to a point in time within the time range that starts when the most recent full backup set is created before the sandbox feature is enabled and ends when the last full backup set is created. You can restore the data only to a point in time when a full backup set is created.
For more information about how to enable the log backup feature for the source database instance, see the following topics:
For information about how to enable the log backup feature for an ApsaraDB RDS for MySQL instance, see Use the log backup feature for an ApsaraDB RDS for MySQL instance.
For information about how to enable the log backup feature for a self-managed database, see Enable or disable incremental log backup.
What is the most recent point in time to which the data of a sandbox instance can be restored?
If the log backup feature is disabled for the source database instance, you can restore the data to the point in time when the last full backup set is created. If the log backup feature is enabled for the source database instance, you can restore the data to the point in time when the last binary log file is created.
If the source database instance is an ApsaraDB RDS for MySQL instance, you can view the backup data on the Backup and Restoration page in the ApsaraDB RDS console.
If the source database instance is a self-managed database, you can view the backup data on the details page of the backup schedule in the DBS console.
Why can I restore the data of a sandbox instance only to a point in time when a full backup set is created?
If the log backup feature is disabled for the source database instance, you cannot restore the data to an arbitrary point in time. You can restore the data only to a point in time when the last full backup set is created. For more information about how to enable the log backup feature for the source database instance, see the following topics:
For information about how to enable the log backup feature for an ApsaraDB RDS for MySQL instance, see Use the log backup feature for an ApsaraDB RDS for MySQL instance.
For information about how to enable the log backup feature for a self-managed database, see Enable or disable incremental log backup.
Do the specifications of sandbox instances affect the time required to restore the data of the sandbox instances?
No, the time required to restore the data of a sandbox instance is irrelevant to the specifications of the sandbox instance. However, sandbox instances with higher specifications provide better performance.
How long does it take to restore the data of a sandbox instance?
The time required to restore the data of a sandbox instance varies based on the point in time to which the data is restored.
If you restore the data to a point in time when a snapshot is created, it takes about two minutes to restore 1 TB of data. We recommend that you use this method.
If you want to restore the data to a specific point in time, you must first restore the data to a point in time when the most recent snapshot is created before the specified point in time. Then, you can restore the data to the specified point in time by replaying binary log files. When you replay binary log files, 512 MB of data can be restored every five minutes on average.
When does DBS generate snapshots for sandbox instances?
DBS generates snapshots for sandbox instances in the following scenarios:
The sandbox feature is enabled for the first time.
A full backup set is created for the source database instance.
Optional. If the log backup feature is enabled for the source database instance, DBS reads the binary log files that are backed up and generates snapshots on a regular basis. The interval at which DBS reads binary log files is about 10 minutes.
How do I connect to a sandbox instance?
You can connect to a sandbox instance by using the virtual private cloud (VPC) endpoint of the sandbox instance. You can view the endpoint of the sandbox instance in the sandbox instance list. The following figure shows an example sandbox instance displayed in the sandbox instance list. 
For more information, see Use DMS to access sandbox instances or Use ECS to access sandbox instances.
Why am I unable to log on to a sandbox instance by using an account that is created after the sandbox instance is created?
A database account that is created after the sandbox instance is created does not exist in the backup data. Therefore, you cannot use this account to log on to the sandbox instance. The configurations of a sandbox instance, such as the accounts and passwords, are the same as those in the backup data of the source database instance that is used to create the sandbox instance. You must log on to a sandbox instance by using the database accounts and passwords that are created before the sandbox instance is created.
How do I retain the data stored in a sandbox instance?
You can use Data Transmission Service (DTS) to migrate the data stored in a sandbox instance to an ApsaraDB RDS for MySQL instance. For more information, see Migrate data from a sandbox instance to an ApsaraDB RDS for MySQL instance.