To insert the IDENTITY column values, Connect CDC must issue a SET IDENTITY_INSERT ON statement at the target. If that statement fails during replication, an error is issued. Whether replication continues or stops on the target depends on the request error mode. If Shutdown apply component is the error mode, replication stops. For more information, see the Advanced User Guide.
Since MS SQL Server does not allow updates to IDENTITY columns, Connect CDC updates always exclude the IDENTITY column. Situations (collisions) where Connect CDC converts a user insert of a source row to an update of a target row can result in different IDENTITY column values in the source row and the target row because the target IDENTITY column does not get updated with the new value. If such a situation occurs, Connect CDC updates the rest of the target row and continues processing.