FDI Task Fails to Be Executed Because DWS Changes to the Read-only State

Cause Analysis

When the DWS disk space reaches the threshold, for example, 80%, or data skew occurs in some tables with a large amount of data, the DWS cluster becomes read-only. On the FDI side, all tasks for accessing DWS stopped abnormally at a certain time point.

Solution

Handle the read-only issue of DWS. After the database service is restored, directly start the FDI task if the task is stopped for less than 6 hours. If the task is stopped for more than 6 hours, data in the channel has expired. In this case, reset the synchronization progress and start the task again. If there are tables whose data has not been fully collected before a full data task is stopped, data of these tables will be collected all over again.

In addition, analyze the causes of the read-only state for database development optimization, or expand the disk space to prevent the problem from recurring.