From MySQL to GaussDB(for MySQL)

Supported Source and Destination Databases

Database Account Permission Requirements

Supported Migration Objects

Precautions

Prerequisites

• You have logged in to the DRS console.
• For details about the DB types and versions supported by real-time migration, see Real-Time Migration.

• You have read DRS Pre-Check Items and Precautions.

Procedure

1. On the Online Migration Management page, click Create Migration Task.
2. On the Create Replication Instance page, specify the task name, description, and the replication instance details, and click Create Now.
   • Task information description

     Table 5 Task information

     Parameter	Description
     Task Name	The task name must start with a letter and consist of 4 to 50 characters. It can contain only letters, digits, hyphens (-), and underscores (_).
     Description	The description consists of a maximum of 256 characters and cannot contain special characters !=<>'&"\

   • Replication instance information

     Table 6 Replication instance settings

     Parameter	Description
     Data Flow	Select To the cloud. The destination is a DB instance on the current cloud.
     Source DB Engine	Select MySQL.
     Destination DB Engine	Select GaussDB(for MySQL).
     Network Type	Available options: VPC, Public network, and VPN or Direct Connect. By default, the value is Public network. VPC is suitable for migrations between cloud databases of the same account in the same region. VPN or Direct Connect is suitable for migrations from on-premises databases to cloud databases or between cloud databases across regions. Public network is suitable for migration from on-premises databases or external cloud databases to destination databases.
     Destination DB Instance	Select the GaussDB(for MySQL) instance you have created.
     Replication Instance Subnet	The subnet where the replication instance resides. You can also click View Subnets to go to the network console to view the subnet where the instance resides. By default, the DRS instance and the destination DB instance are in the same subnet. You need to select the subnet where the DRS instance resides, and there are available IP addresses for the subnet. To ensure that the replication instance is successfully created, only subnets with DHCP enabled are displayed.
     Migration Type	Full: This migration type is suitable for scenarios where service interruption is acceptable. All objects in non-system databases are migrated to the destination database at one time, including tables, views, stored procedures, and triggers. NOTE: If you are performing a full migration, do not perform operations on the source database. Otherwise, data generated in the source database during the migration will not be synchronized to the destination database. Full+Incremental: This migration type allows you to migrate data without interrupting services. After a full migration initializes the destination database, an incremental migration initiates and parses logs to ensure data consistency between the source and destination databases. NOTE: If you select Full+Incremental, data generated during the full migration will be continuously synchronized to the destination database, and the source remains accessible.
     Destination DB Instance Access	Read-only During the migration, the destination database is read-only. After the migration is complete, it restores to the read/write status. This option ensures the integrity and success rate of data migration. If a migration task fails, the destination database restores to the read/write state. After the migration task is resumed, the destination database becomes read-only. The access settings of the destination instance are also affected by the access settings of the DB instance itself. Therefore, you are advised not to set the access settings of the DB instance on the RDS console. If the destination database is set to read-only for a migration task, you can disable read-only on the task details page. After read-only is disabled, the destination database cannot be set back to read-only. Even if the migration task fails and then resumed and started, the destination database cannot be set to read-only. Read/Write During the migration, the destination database can be queried or modified. Data being migrated may be modified when operations are performed or applications are connected. It should be noted that background processes can often generate or modify data, which may result in data conflicts, task faults, and upload failures. Do not select this option if you do not fully understand the risks. Set the destination database to Read/Write only when you need to modify other data in the database during the migration. The task cannot be modified after being created.
     Specify EIP	This parameter is available when you select Public network for Network Type. Select an EIP to be bound to the DRS instance. DRS will automatically bind the specified EIP to the DRS instance and unbind the EIP after the task is complete.

   • AZ

     Table 7 Task AZ

     Parameter	Description
     AZ	Select the AZ where you want to create the DRS task. Selecting the one housing the source or destination database can provide better performance.

   • Enterprise Project and Tags

     Table 8 Enterprise Project and Tags

     Parameter	Description
     Enterprise Project	An enterprise project you would like to use to centrally manage your cloud resources and members. Select an enterprise project from the drop-down list. The default project is default.
     Tags	Tags a task. This configuration is optional. Adding tags helps you better identify and manage your tasks. Each task can have up to 20 tags. After a task is created, you can view its tag details on the Tags tab. For details, see Tag Management.

   Note

   If a task fails to be created, DRS retains the task for three days by default. After three days, the task automatically stops.

3. On the Configure Source and Destination Databases page, wait until the replication instance is created. Then, specify source and destination database information and click Test Connection for both the source and destination databases to check whether they have been connected to the replication instance. After the connection tests are successful, select the check box before the agreement and click Next.
   • Source database configuration

     Table 9 Source database settings

     Parameter	Description
     IP Address or Domain Name	The IP address or domain name of the source database.
     Port	The port of the source database. Range: 1 – 65535
     Database Username	The username for accessing the source database.
     Database Password	The password for the database username.
     SSL Connection	SSL encrypts the connections between the source and destination databases. If SSL is enabled, upload the SSL CA root certificate. NOTE: The maximum size of a single certificate file that can be uploaded is 500 KB. If SSL is disabled, your data may be at risk.

     Note

     The IP address, domain name, username, and password of the source database are encrypted and stored in DRS, and will be cleared after the task is deleted.

   • Destination database configuration

     Table 10 Destination database settings

     Parameter	Description
     DB Instance Name	The GaussDB(for MySQL) instance selected during the migration task creation. This parameter cannot be changed.
     Database Username	The username for accessing the destination database.
     Database Password	The password for the database username.
     Migrate Definer to User	Indicates whether to migrate the Definers of all source database objects to the destination database user entered during the connection test. Yes The Definers of all source database objects will be migrated to the user. Other users do not have permissions for database objects unless these users are authorized. For details on authorization, see How Do I Maintain the Original Service User Permission System After Definer Is Forcibly Converted During MySQL Migration?

     Note

     The username and password of the destination database are encrypted and stored in DRS, and will be cleared after the task is deleted.

4. On the Set Task page, select migration objects and click Next.

   Table 11 Migrate Object

   Parameter	Description
   Flow Control	You can choose whether to control the flow. Flow Control takes effect in the full phase only. Yes You can customize the maximum migration speed. During the migration, the migration speed of each task (or each subtask in multi-task mode) does not exceed the value of this parameter. In addition, you can set the time range based on your service requirements. The traffic rate setting usually includes setting of a rate limiting time period and a traffic rate value. Flow can be controlled all day or during specific time ranges. The default value is Always. A maximum of 10 time ranges can be set, and they cannot overlap. The flow rate must be set based on the service scenario and cannot exceed 9,999 MB/s. No The migration speed is not limited and the outbound bandwidth of the source database is maximally used, which will increase the read burden on the source database. For example, if the outbound bandwidth of the source database is 100 MB/s and 80% bandwidth is used, the I/O consumption on the source database is 80 MB/s. NOTE: Flow control mode takes effect only during a full migration. You can also change the flow control mode after creating a task. For details, see Modifying the Flow Control Mode.
   Migrate Account	During a database migration, accounts need to be migrated separately. You can choose whether to migrate the accounts based on service requirements. If you select Yes, you can select the accounts to be migrated as required. Yes If you need to migrate accounts, see Migrating Accounts. No During migration, accounts, permissions, and passwords are not migrated.
   Create Indexes Along With Table Structure	Indicates whether to create indexes along with the table structure in the full migration phase. Yes: Indexes are migrated when the table structure is migrated in the full migration phase. No: Indexes are migrated separately after data migration.
   Migrate Object	The left pane displays the source database objects, and the right pane displays the selected objects. You can choose to migrate all objects, tables, or databases based on your service requirements. All: All objects in the source database are migrated to the destination database. After the migration, the object names will remain the same as those in the source database and cannot be modified. Tables: The selected table-level objects will be migrated. Databases: The selected database-level objects will be migrated. If the source database is changed, click in the upper right corner before selecting migration objects to ensure that the objects to be selected are from the changed source database. NOTE: If you choose not to migrate all of the databases, the migration may fail because the objects, such as stored procedures and views, in the databases to be migrated may have dependencies on other objects that are not migrated. To prevent migration failure, migrate all of the databases. If an object name contains spaces, the spaces before and after the object name are not displayed. If there are two or more consecutive spaces in the middle of the object name, only one space is displayed. The name of the selected migration object cannot contain spaces. To quickly select the desired database objects, you can use the search function.

5. On the Check Task page, check the migration task.
   • If any check fails, review the cause and rectify the fault. After the fault is rectified, click Check Again.
   • If the check is complete and the check success rate is 100%, click Next.
     Note

     You can proceed to the next step only when all checks are successful. If there are any items that require confirmation, view and confirm the details first before proceeding to the next step.

6. On the displayed page, specify Start Time, Send Notifications, SMN Topic, Delay Threshold (s), and Stop Abnormal Tasks After and confirm that the configured information is correct and click Submit to submit the task.

   Table 12 Task startup settings

   Parameter	Description
   Start Time	Set Start Time to Start upon task creation or Start at a specified time based on site requirements. The Start at a specified time option is recommended. NOTE: The migration task may affect the performance of the source and destination databases. You are advised to start the task in off-peak hours and reserve two to three days for data verification.
   Send Notifications	This parameter is optional. If the status, latency metric, or data of the migration task is abnormal, DRS will send you a notification.
   SMN Topic	This parameter is available only after you enable Send Notifications and create a topic on the SMN console and add a subscriber.

7. After the task is submitted, view and manage it on the Online Migration Management page.
   • You can view the task status. For more information about task status, see Task Statuses.
   • You can click in the upper right corner to view the latest task status.
   • After the full migration is complete, you can use data comparison to check whether the data is consistent before and after the migration.
   • By default, DRS retains a task in the Configuration state for three days. After three days, DRS automatically deletes background resources, but the task status remains unchanged. When you reconfigure the task, DRS applies for resources again.
   • For a public network task, DRS needs to delete background resources after you stop the task. The EIP bound to the task cannot be restored to the Unbound state until background resources are deleted.