ORA-16855: Transport Lag Has Exceeded Specified Threshold in Data Guard !!
The ORA-16855 error indicates that the transport lag (the delay in sending redo data from the primary to the standby database) has exceeded the specified threshold. Cause: The current apply lag has exceeded the value specified by the ApplyLagThreshold configurable property. This can be due to either a significant transport lag or poor performance of … Read more