Migration Management

Available in VPC

In Migration Management, you can create migration tasks to automate the step-by-step tasks required for migration. You can also check the status of migration tasks and restart, stop, complete, or delete them as needed.

Database migration proceeds through backup, recovery, and data synchronization stages.

• Backup (export): Backs up data from the source DB.
• Recovery (import): Recovers data to the target DB.
• Data synchronization (replication): Synchronizes data between the source and target DBs.

Prepare for migration

Before creating a migration task and starting migration, complete the following items:

• Configure access to the source and target DBs. (See Configure access to the source and target databases.)
• Create a source DB endpoint. (See Create an endpoint.)
• Verify that the target DB is running.
• If the source DB uses procedure definer accounts, create accounts on the target DB with the same ID and host. (See Manage DB user.)
• If you changed the source DB configuration, apply the same changes to the target DB. (See Manage DB config.)
• If the target DB contains databases with the same names as the source DB, delete them from the target database.

Create a migration task

You can easily migrate data from the source DB to the target DB by creating a migration task.

To create a migration task:

1. In the VPC environment of the NAVER Cloud Platform console, navigate to Menu > All services > Database > Database Migration Service.

2. Click the Migration management menu.

3. Click [Create a migration task].

4. Enter the following information:

   • Migration task name: Enter a name.
   • Source DB: Select the source DB identifier from the source DB endpoint.
     • [Edit an endpoint]: Click to modify the source DB connection information configured for the endpoint. (See Create an endpoint.)
   • Endpoint URL, DB port, DB user: Display the source database information configured for the endpoint when you select the Source DB.
   • Target DB: Select the target DB created on NAVER Cloud Platform.

5. Click [Test connection] to test the connection between the source and target DBs.

   • If the test succeeds, the DB engine version and GTID mode information are entered automatically.
   • If an error occurs, a notification popup appears.

6. Enter the following information:

   • Backup type: Select mysqldump or mydumper.
   • Thread limit:
     • If the backup type is mysqldump, the value is fixed at 1.
     • If the backup type is mydumper, enter a number from 2 to 10. (However, the number of threads that can be entered is limited by the CPU and memory specifications of the target DB server.)
   • Target databases: Select 1 or more databases to migrate.

7. Click [Start migration task].

   • The button becomes enabled after the connection test completes.

8. When the notification popup appears, click [OK].

   • Migration starts.

View migration task information

To view information about a migration task:

1. In the VPC environment of the NAVER Cloud Platform console, navigate to Menu > All services > Database > Database Migration Service.
2. Click the Migration management menu.
3. In the task list, you can review the basic information, or click a specific task to view its Task information.
   • The basic information available in the task list is as follows.

     Item	Description
     Task status	The current status of the task. In progress: Migration is in progress. Abnormally terminated: Migration ended abnormally due to an error. Stopped: The task was forcibly stopped. Completed: The connection to the source DB is fully disconnected, and you cannot restart or revert.
     Execution stage	Display the current execution step (shown only when the Task status is in progress) Exporting: It is backing up data from the source DB. Importing: It is recovering data to the target DB. Replication: It is synchronizing data between the source and target DBs.
     Source DB	It is the source DB identifier you configured.
     Target DB	It is the target DB name you configured.
     Start time	The time when the migration started.
     End time	The end time if migration completed.
     Elapsed time	If completed, shows the total migration duration. If in progress, shows the elapsed time since migration started.
     Migration size	It is the size of the source DB backup files.

   • The task information available when you click a task is as follows.

     Item	Description
     Source DB engine version	The DBMS type and version of the source DB.
     Target DB engine version	The DBMS type and version of the target DB.
     Migration start time	The time when the migration started.
     Migration end time	The end time if migration completed.
     Migration Status	The current status of the task.
     Target DB server name	The name of the target DB server.
     Execution stage	The status of each execution stage when the Task status is In progress (Before, In progress, Completed, Error). Exporting: Backup progress for the source DB. Importing: Recovery progress for the target DB. Replication: Data synchronization progress between the source and target databases. If the status is Error, click [View error] to review the error details.
     Backup type	The backup tool type used for migration (mysqldump or mydumper).
     Thread count	The number of threads used for backup and recovery.

4. If an error occurs during any execution step (Exporting, Importing, or Replication), the progress status will be displayed as Error. You can view detailed error information by clicking [View error]. To proceed with the following steps:

   Execution stage	Error handling
   Exporting	Check the source DB connection information and privileges, resolve the issue, and then restart the migration.
   Importing	Check the target DB status and disk capacity, resolve the issue, and then restart the migration. Depending on the cause of the error, you may need to delete and recreate the migration to proceed.
   Replication	After reviewing the error details, you can skip the error by clicking [Skip replication error].

Skip replication error

If a replication error occurs during the replication stage, clicking [Skip replication error] allows you to skip the transaction where the error occurred and continue with data synchronization.

• Once the skip is complete, replication automatically resumes and the execution stage transitions to the In progress state.
• Skip replication errors is available only during the replication stage and does not apply to errors during the exporting or importing stages.

Check table status

After replication is complete, the service automatically checks for missing tables and unrestored data between the source DB and target DB. Check the results in the Check table status component of the task information interface. The following describes the check table status items:

• Status: Check result status.
  • No issues detected: No differences are found between the source DB and target DB during the analytics-based check.
  • Issues detected: Missing tables or unrestored data are detected for some tables.
• Check completion time: Time when the check was completed and the time taken.
• Check result: Summary of the analytics-based check results.
  • When the status is No issues detected: Displayed in Source ↔ Target 간 N개 테이블 통계 기반 확인 완료 format.
  • When the status is Issues detected: Displayed in 이상 없음 N / 이상 탐지 N format, and a details table appears below.
    • DB name: Name of the DB where an issue is detected.
    • Table name: Name of the table where an issue is detected.
    • Detected issue: Detected reason (example: Target DB에 테이블이 존재하지 않음).

The Check table status runs automatically once when the Replication stage is complete. If Replication is completed again after you click [Stop] and [Restart] during the replication stage, the service automatically runs the check again.

Restart migration task

To restart a migration task that ended abnormally or was stopped:

1. In the VPC environment of the NAVER Cloud Platform console, navigate to Menu > All services > Database > Database Migration Service.
2. Click the Migration management menu.
3. In the task list, select the task to restart and click [Restart].
4. When the notification popup appears, click [OK].
   • The Task status changes to In progress.

Stop a migration task

To stop a migration task in progress:

1. In the VPC environment of the NAVER Cloud Platform console, navigate to Menu > All services > Database > Database Migration Service.
2. Click the Migration management menu.
3. In the task list, select the task to stop and click [Stop].
4. When the notification popup appears, click [OK].
   • The Task status changes to Stopped.

Complete a migration task

Ends data synchronization with the source database and makes the target database available for operation.

• This is available only when the migration task's Task status is In progress and the Execution stage is Replication completed.

To complete a migration task:

1. In the VPC environment of the NAVER Cloud Platform console, navigate to Menu > All services > Database > Database Migration Service.
2. Click the Migration management menu.
3. In the task list, select the task to complete and click [Complete].
4. When the notification popup appears, click [OK].

Delete a migration task

You can delete migration task information. Deletion is available only when the Task status of the migration task is abnormally terminated, stopped, or completed.

To delete migration task information:

1. In the VPC environment of the NAVER Cloud Platform console, navigate to Menu > All services > Database > Database Migration Service.
2. Click the Migration management menu.
3. Select the task to delete from the list and click [Delete].
4. When the notification popup appears, click [OK].