Restoring a DB Instance from Backups

Scenarios

This section describes how to use an automated or manual backup to restore a DB instance to the status when the backup was created. The restoration is at the DB instance level.

When you restore a DB instance from a backup file, the backup file is downloaded from OBS and then restored to the DB instance at an average speed of 40 MB/s.

Constraints

• Constraints on restoring data to an existing DB instance:
  • If the target existing DB instance has been deleted, data cannot be restored to it.
  • Restoring to an existing DB instance will overwrite data on it and cause the existing DB instance to be unavailable.
  • To restore backup data to an existing DB instance, the selected DB instance must use the same DB engine and the same or a later version than the original DB instance.
  • Ensure that the storage space of the selected existing DB instance is greater than or equal to the storage space of the original DB instance. Otherwise, data will not be restored.

Procedure

1. Log in to the management console.
2. Click in the upper left corner of the page and choose Databases > Relational Database Service.
3. On the Backups page, select the backup to be restored and click Restore in the Operation column.

   Alternatively, click the target DB instance on the Instances page. On the displayed page, choose Backups & Restorations. On the displayed page, select the backup to be restored and click Restore in the Operation column.

4. Select a restoration method and click OK.
   • Create New Instance

     The Create New Instance page is displayed.

     • The DB engine and engine version of the new instance are the same as those of the original instance.
     • Storage space of the new DB instance is the same as that of the original DB instance by default and the new instance must be at least as large as the original DB instance.
   • Restore to Existing
     1. Select "I acknowledge that restoring to an existing DB instance will overwrite data on the instance and will cause the existing DB instance to be unavailable during the restoration. Only DB instances that can be used as target instances for the restoration are displayed here. Eligible instances must have the same DB engine type, version, and at least as much storage as the instance being restored." and click Next.
     2. Confirm the information and click OK.

5. View the restoration result. The result depends on which restoration method was selected:
   • Create New Instance

     A new DB instance is created using the backup data. The status of the DB instance changes from Creating to Available.

     The new DB instance is independent from the original one. If you need read replicas to offload read pressure, create one or more for the new DB instance.

     After the new instance is created, a full backup will be automatically triggered.

   • Restore to Existing

     On the Instances page, the status of the target existing DB instance changes from Restoring to Available. If the target existing DB instance contains read replicas, the read replica status is the same as the target existing DB instance status.

     After the restoration is complete, a full backup will be automatically triggered.