Oracle Database 12c: RAC and Grid Infrastructure Administration — Question 101

Your Data Guard environment consists of these components and settings:
1. A primary database
2. Two remote physical standby databases
3. The redo transport mode is set to SYNC.
4. Real-time query is enabled for both standby databases.
5. The DB_BLOCK_CHECKING parameter is set to TRUE on both standby databases.
You notice an increase in redo apply lag time on both standby databases.
Which two would you recommend to reduce the redo apply lag on the standby databases?

Answer options

• A. Increase the size of the buffer cache on the physical standby database instances.
• B. Increase the number of standby redo log files on the standby databases.
• C. Decrease the redo log file size on the primary database.
• D. Lower DB_BLOCK_CHECKING to MEDIUM or LOW on the standby databases.
• E. Increase the size of standby redo log files on the standby databases.

Correct answer: A, D

Explanation

Increasing the buffer cache on the physical standby databases (Option A) allows for more efficient processing and can help alleviate redo apply lag. Lowering DB_BLOCK_CHECKING to MEDIUM or LOW (Option D) reduces the overhead associated with block checking, which can also improve performance. The other options do not directly address the causes of redo apply lag as effectively as A and D.