Data Disaster Recovery provides features for PolarDB-X instances, such as geo-redundancy, long-term archiving, and distributed backup. This topic describes how to use Data Disaster Recovery to logically back up and restore a PolarDB-X instance.
Prerequisites
A PolarDB-X 1.0 instance is created. The data of the PolarDB-X 1.0 instance is stored in an ApsaraDB RDS for MySQL instance that runs MySQL 5.x or 8.x.
Features
Feature | Description |
SQL file backup | Data Disaster Recovery logically backs up data in the JSON format. |
Geo-redundancy | Data Disaster Recovery can back up a PolarDB-X instance to an Object Storage Service (OSS) bucket that is located in the specific destination region and restore the backup data to a new PolarDB-X instance that is deployed in the source region, destination region, or another region. |
Long-term archiving | Data Disaster Recovery can retain your backup data for up to ten years. After ten years, Data Disaster Recovery transfers backup sets to Archive Storage. |
Backup speed limit | Data Disaster Recovery allows you to limit the backup speed to reduce the negative impact of backup operations on database performance. |
Distributed backup | Data Disaster Recovery provides the distributed backup feature for backup schedules of the large or xlarge type. This feature allows you to back up and restore multiple nodes at the same time. |
Create a backup schedule
For more information, see Create a backup schedule.
When you purchase a backup schedule, set the Data Source Type parameter to PolarDB-X and the Backup Method parameter to Logical Backup.
Configure a backup schedule
Log on to the Data Management (DMS) console V5.0.
In the top navigation bar, choose .
NoteIf you use the DMS console in simple mode, move the pointer over the
icon in the upper-left corner of the DMS console and choose . On the Backup Schedules page, find the backup schedule that you want to configure and click Configure Backup Schedule in the Actions column.
In the Configure Backup Source and Destination step, configure the backup source and destination, and click Next in the lower-right corner of the page.

Section
Parameter
Description
N/A
Schedule Name
The name of the backup schedule. Data Disaster Recovery automatically generates a backup schedule name. We recommend that you enter a descriptive name that is easy to identify. Backup schedule names do not need to be unique.
Backup Source Information
Backup Mode
The method that is used to back up data. By default, the backup method that you selected when you purchased the backup schedule is used. In this example, Logical Backup is used.
Database Location
The location of the source database. Select PolarDB-X Instance.
Instance Region
The region in which the source database instance resides.
Database Type
The type of the source database. Select PolarDB-X (Formerly DRDS).
ID of PolarDB-X Instance
The ID of the PolarDB-X instance on which the source database is deployed.
Database Name
The name of the source database.
Database Account
The username of the account that is used to connect to the source database. The account must have permissions to back up the database. For more information, see Required permissions for different types of database accounts.
Password
The password of the account that is used to connect to the database that you want to back up.
After you enter the username and password of the database account, click Test Connection next to the password to check whether the information about the database that you want to back up is valid. If the specified parameters are valid, the Test Passed message is displayed. If the Test Failed message is displayed, click Check next to Test Failed. Modify the information about the database that you want to back up based on the check results.
Compliance warranty regarding cross-border data transfers
Read and agree to the compliance commitment by selecting the check box.
Backup Destination Information
Backup Storage Type
The storage type of the backup data. Valid values:
DBS Storage (recommended): Backup data is stored in Data Disaster Recovery without the need to create an Object Storage Service (OSS) bucket. You are charged based on the volume of your data that is stored in Data Disaster Recovery. For more information about the billing method, see Storage fees.
OSS For User: You must create a bucket in the OSS console in advance. For more information, see Create buckets.
NoteIn this example, DBS Storage (recommended) is selected. If you select OSS For User, you must configure the OSS Bucket Name parameter. Only the Standard storage class is supported.
If you want to store a large amount of data, we recommend that you purchase a subscription storage plan to offset Data Disaster Recovery built-in storage fees. Data Disaster Recovery storage plans are more cost-efficient than the pay-as-you-go billing method.
Storage Encryption
The method that is used to encrypt the stored data. Valid values:
Encrypted (recommended): AES-256 is used to encrypt the stored data.
The server-side encryption feature is used in OSS. When you upload an object to a bucket for which server-side encryption is enabled, OSS encrypts and stores the object. When you download the encrypted object from OSS, OSS decrypts the object and returns the decrypted object to you. For more information, see Server-side encryption.
Non-encrypted: The stored data is not encrypted.
In the Edit Backup Objects step, click Edit Backup Objects.
Data Disaster Recovery allows you to back up only an entire distributed database instance.
In the Configure Backup Time step, configure the parameters that are described in the following table and click Next.
Parameter
Description
Full-scale Backup Frequency
The frequency of the backup schedule. Valid values: Periodic Backup and Single Backup.
NoteIf you select Periodic Backup, you must configure the Full Data Backup Recurrence and Start At parameters.
Full Data Backup Recurrence
The days of the week on which Data Disaster Recovery runs the backup schedule. You can select one or more days of a week. Select at least one day of the week.
Start At
The start time of the backup. We recommend that you set a point in time within off-peak hours. Example: 01:00.
NoteIf a previous full data backup is not finished at the start time of the next backup, Data Disaster Recovery skips the next backup.
Incremental Backup
Data Disaster Recovery does not support the incremental backup for PolarDB-X instances.
Maximum Concurrent Threads for Full Data Backup
The maximum number of concurrent threads available for a full backup. You can set this parameter to adjust the backup speed. For example, you can reduce the number of backup threads to minimize impacts on the database.
In the Edit Lifecycle step, configure the lifecycle for a full backup set in the Configure Full Data Backup Lifecycle section.
After the preceding configurations are complete, click Precheck in the lower-right corner of the page.
If the Precheck Passed message appears, click Start Task.
NoteIf the backup schedule status changes to Running, the backup schedule takes effect.
If an exception or error occurs when you start the backup schedule, troubleshoot the exception or error at the earliest opportunity. For more information, see How do I fix errors for an abnormal backup schedule? If your issue persists after you use the solution that is provided in the preceding topic, contact technical support in the DingTalk group (ID: 35585947).
Restore a PolarDB-X instance
Log on to the DMS console V5.0.
In the top navigation bar, choose .
NoteIf you use the DMS console in simple mode, move the pointer over the
icon in the upper-left corner of the DMS console and choose . On the Backup Schedules page, find the backup schedule that you want to manage and click Manage in the Actions column.
On the Configure Task page, click Restore Database in the upper-right corner.
In the Set Time Restored To step of the Create Restore Task wizard, configure the parameters that are described in the following table and click Next.

Section
Parameter
Description
N/A
Task Name
The name of the restore task. Data Disaster Recovery automatically generates a task name. We recommend that you specify a name that can help you identify the task. Task names do not need to be unique.
Set Time Restored To
Time Range Available to Restore
The time range from the point in time when the first full backup set is created to the point in time when the latest full backup set is created. The database can be restored to a point in time within the time range.
Restore To
The point in time to which you want to restore the source database. The value must be within the time range that is specified by the Time Range Available to Restore parameter. You can set this parameter to the time when a full backup set is created.
Configure Destination Database
Database Location
The location of the destination database. Select PolarDB-X Instance.
Instance Region
The region in which the destination instance resides.
Database Type
The type of the destination database. Select PolarDB-X (Formerly DRDS).
PolarDB Instance ID
The ID of the destination PolarDB-X instance. If you restore data to the source PolarDB-X instance, the data in the source database may be overwritten. We recommend that you restore the data to a new PolarDB-X instance.
Database Name
The name of the destination database.
Database Account
The username of the account used to connect to the destination database. The account must have the read/write permissions on the destination database.
Password
The password of the account that is used to connect to the destination database.
Compliance warranty regarding cross-border data transfers
Read and agree to the compliance commitment by selecting the check box.
In the Configure Objects to Restore step, configure the parameters that are described in the following table and click Precheck.
Parameter
Description
Conflict Handling
You can select only Fail When Object with the Same Name Exists for the Conflict Handling parameter.
Objects to Restore
Select the database or table that you want to restore in the Available section and click the right arrow to add it to the Selected section.
NoteData Disaster Recovery allows you to restore a single database or table. This reduces the amount of data to be restored and shortens the recovery time objective (RTO).
In the Configure Objects to Restore step, configure the parameters that are described in the following table and click Precheck.
Parameter
Description
Conflict Handling
By default, Rename Object with the Same Name is selected for the Conflict Handling parameter. For example, if the
job_infotable to be restored shares the same name with a table in the destination database, the system renames the restored table in the following format:job_info_dbs_<Restore task ID>_<Timestamp>.Objects to Restore
Select the database or table that you want to restore in the Available section and click the rightwards arrow to add it to the Selected section.
NoteData Disaster Recovery allows you to restore some databases by database or table. This reduces the amount of data to be restored and shortens the RTO. For more information about the supported restoration granularity, see Supported database types and features.
If the Precheck Passed message appears in the Precheck dialog box, click Start Task.
To view the database restoration progress, click Restore Tasks in the left-side navigation pane.
NoteThe restoration duration depends on the specifications of the backup schedule and the size of the database to be restored. The restoration duration is shorter for a backup schedule with higher specifications. For more information, see Performance tests on logical backup and physical backup.