This topic describes how to download a conflict log file when data conflicts occur during data migration.
Background information
Conflicting data refers to the situation that the target already has data with the corresponding unique key when the same unique key data is written from the source to the target by INSERT. This can trigger the detection of conflicting data. The following scenarios can lead to the presence of conflicting data:
The target contains dirty data, or business data is written to the target during data migration.
During full or incremental synchronization, the component was paused and then restored (restarted). Since data is processed in batches, restoring and replaying the entire unfinished batch can result in duplicate writes, leading to conflicting data.
During the process of catching up on incremental synchronization delays, incremental data is replayed from the full migration start timestamp of the corresponding table. This can result in duplicate writes, leading to conflicting data.
Conflicting data can affect data consistency. Starting from V4.3.0, OMS allows you to download conflict log files to monitor and view conflicting data. When data conflicts occur in the full migration, incremental synchronization, or reverse increment step of a data migration task, the data migration task list page displays a ⚠️ icon to indicate that conflicting data exists. You can download the conflict log files as needed.
You can specify the system parameter connector.conflict.log.config to configure the settings for downloading conflict log files in the full migration, incremental synchronization, or reverse incremental synchronization step of a data migration task. For more information, see Modify system parameters.
Procedure
Log in to the OMS console.
In the left-side navigation pane, click Data Migration.
On the Data Migration page, hover the pointer over the icon of the corresponding step in the target task, and click Download.
In the Download Conflict Data dialog box, select the file that you want to download.
Click Download. After the download is completed, you can view the file locally.