Absolute Free 1Z0-902 Exam Practice for Comprehensive Preparation 

Write-back flash cache is on by default for High Capacity Storage Servers in High Redundancy configurations.

When enabling write-back flash cache in a rolling manner, DBCLI should be used to inactivate the grid disks on all cells first. 

Failure groups are created for each grid disk to ensure mirror copies are written to the same storage server for faster recovery after a physical disk failure. 

Failure groups contain all ASM disks in a single storage server preventing mirror copies being written to the same storage server.

They ensure that the ASM Flex instances are enabled on a maximum of two database servers or VMs per cluster.

YOU query VSSYSTEM_EVENTS and filter for the event 'cell physical IO interconnect bytes returned by smart scan', associated to your table. 

You query v$segment_statistics and filter for the Object ID of your table from dba_objects and the the column STATISTIC_NAME='optimized physical reads'. 

You run the CellCli-command list activerequest , filtering for the attributes ioReason and objectNumber, that you specify as 'Smart Scan' and the Object ID of your table from DBA_OBJECTS.