Overview

This topic describes the considerations, process, and limitations for upgrading OceanBase Migration Service (OMS) to V4.2.3.

Background

OMS V3.2.1 and later support rollback during the upgrade. We recommend that you use a backup tool to back up the existing database, such as db_oms, to an SQL file such as db_oms_bak.sql before starting the upgrade. The new OMS image will run on the original db_oms database, and the database backup file such as db_oms_bak.sql can be used for rollback.

Upgrade process

1. If high availability (HA) is enabled, disable it first.

2. Back up the databases.

3. Load the downloaded OMS installation package to the local image repository of the Docker container.

4. Start the container of OMS V4.2.3

   The name of the MetaDB for the container of OMS V4.2.3 must be the same as that of the MetaDB before the upgrade. In addition, the three disk mounting paths must be the same as those before the upgrade.

5. Go to the new container.

6. (Optional) After the CM/Supervisor component is started, execute the .jar upgrade package.

   Note

   If you upgrade OMS from V4.0.2 or later to V4.2.3, you can skip this step.

7. Perform metadata initialization in the root directory.

8. After the docker_init.sh script is executed, verify that the server list is normal and all servers are in the Online state.

9. On the System Parameters page, enable HA and configure the related parameters.

   The following table shows status changes of components and projects when HA is enabled or disabled.

   Project/Component status before upgrade	After upgrade (HA disabled)	After upgrade (HA enabled)
   The project runs normally. The Incr-Sync component runs normally. The store component runs normally.	The project status remains unchanged. The Incr-Sync component is abnormal. The store component is abnormal.	The project status remains unchanged. The Incr-Sync component automatically starts. The store component is automatically created based on the configurations. For more information, see Modify HA configurations.
   The project failed. The Incr-Sync component is abnormal. The store component is abnormal.
   The project is suspended. The Incr-Sync component is suspended. The store component runs normally.	The project status remains unchanged. The Incr-Sync component is suspended. The store component is abnormal.	The project status remains unchanged. The Incr-Sync component is suspended. The store component is automatically created based on the configurations. For more information, see Modify HA configurations.

10. (Optional) Perform the rollback operation as needed.

11. After the upgrade is complete, clear the browser cache before you log on to OMS.

Limitations

• OMS V3.2.1 and later can be directly upgraded to OMS V4.2.3. If you use OMS of a version earlier than V3.2.1, you must upgrade it first to V3.2.1.

• If an oblogproxy project exists in the current version, the upgrade is not supported. You must redeploy OMS V4.2.3 and create a data migration or synchronization project.

• Before you start the upgrade, make sure that data is synchronized in quasi-real-time between the source and destination in data migration and synchronization projects created by using the earlier version of OMS, and that the forward switchover of the projects is completed. We do not recommend that you use the new version of OMS to perform the forward switchover.

• Before you upgrade OMS V3.2.1 or V3.2.2, if DDL synchronization is involved, you must add the dbType parameter for the Incr-Sync component. Otherwise, the data synchronization projects cannot run. You must fix the issue after the upgrade. For more information, see What do I do to resolve compatibility issues when I upgrade OMS V3.2.1 or V3.2.2 to V4.2.3?

  Notice

  If you use OMS V3.3.0 and it contains data synchronization projects created by using OMS V3.2.1 or V3.2.2, the preceding issue may occur. You can fix it by using the same methods.

  You can check whether the dbType or db_type parameter exists in the Source configuration file of the Incr-Sync component. If any of the two parameters exists, no fix is required.