Explanation/Reference:
Explanation:
Exadata storage cells include Oracle Hardware Assisted Resilient Data (HARD) to provide a unique level of validation for Oracle block data structures such as data block address, checksum.
and magic numbers prior to allowing a write to physical disks. HARD validation with Exadata is automatic (setting DB_BLOCK_CHECKSUM is required to enable checksum validation). The HARD checks transparently handle all cases including Oracle ASM disk rebalance operations and disk failures.
Incorrect:
Not A:The checksum is used to validate that a block is not physically corrupt, detecting corruptions caused by underlying disks, storage systems, or I/O systems. Checksums do not ensure logical consistency of the block contents.
Not B: MAA recommends that you set DB_BLOCK_CHECKING=MEDIUM or FULL on the physical standby as a minimum practice to prevent the standby from various logical block corruptions.
Not D: The recommendation is:
On the primary database: DB_LOST_WRITE_PROTECT=TYPICAL (default TYPICAL on Exadata) On the Data Guard Physical Standby Database: DB_LOST_WRITE_PROTECT=TYPICAL
Not E: Protection from a broad range of, but not all disasters
While not a full disaster recovery (DR) solution, an Extended Distance
Oracle RAC or Oracle RAC One Node deployment will provide protection from a broad range of disasters.
For a full DR protection Oracle recommends deploying an Oracle RAC together with a local and a remote Oracle Data Guard setup as described in the Maximum Availability Architecture (MAA).