Remove Exadata Flash Grid disk and configure as normal Flash

In previous blog we have created Grid Disk on Flash Disk. Here we are removing Flash Grid Disk and configuring normal Flash Cache.

Step-1
Remove or move database or any contents to some another ASM Disk group

Step-2
Drop ASM disk group which was create on flash disk

Step-3
Drop all the flash grid disk

CellCLI> drop griddisk all prefix=flashdisk force
GridDisk FlashDisk_FD_00_exa1cel01 successfully dropped
GridDisk FlashDisk_FD_01_exa1cel01 successfully dropped
GridDisk FlashDisk_FD_02_exa1cel01 successfully dropped
GridDisk FlashDisk_FD_03_exa1cel01 successfully dropped
GridDisk FlashDisk_FD_04_exa1cel01 successfully dropped
GridDisk FlashDisk_FD_05_exa1cel01 successfully dropped
GridDisk FlashDisk_FD_06_exa1cel01 successfully dropped
GridDisk FlashDisk_FD_07_exa1cel01 successfully dropped

Step-4

Configure Exadata Flash Disk as Grid Disk

We can use Flash Cache as Grid Disk to create the ASM disk group and can keep the database on flash disk but this is not reccomended solution as flash cache performs better to cache frequently access data rather than creating database on it.

If you want put your database on Flash cache than below are the steps to configure FLASH CACHE as ASM disk.

Steps:

1. Drop existing flash cache

2. Create flashcache with required size

3. Create grid disk from Flash Cache

4. Create ASM disk group on top of the Flash Griddisk

5. Put your database on ASM disk group which has been configured from Flash grid disk

Step-1

CellCLI>drop flashcache

If it gives error like below

CELL-02769: Cannot complete flash cache drop on: FD_03_ex01cceladm03. 

Received error: CELL-02732: There may be data not synchronized to the grid disks (dirty data) in flash cache.

Use ALTER FLASHCACHE to flush the dirty data and to stop caching, and then retry the command.

This error comes because flash cache mode has been configured as writeback hence some of the dirty data are still not written to the grid disks.

To overcome from this error flush all the flashcache

CellCLI>  alter flashcache all flush

Flash cache exa1cel01_FLASHCACHE altered successfully

CellCLI> drop flashcache 

Flash cache exa1cel01_FLASHCACHE successfully dropped 

Step-2

Cellcli - Help

CellCLI> help

HELP [topic]

    Available Topics:

        ALTER

        ALTER ALERTHISTORY

        ALTER CELL

        ALTER CELLDISK

        ALTER GRIDDISK
        ALTER IBPORT

        ALTER IORMPLAN

        ALTER LUN
        ALTER PHYSICALDISK
        ALTER QUARANTINE

        ALTER THRESHOLD

        ASSIGN KEY

        CALIBRATE

        CREATE

        CREATE CELL

        CREATE CELLDISK

        CREATE FLASHCACHE

        CREATE GRIDDISK

        CREATE KEY
        CREATE QUARANTINE

        CREATE THRESHOLD

        DESCRIBE

        DROP

        DROP ALERTHISTORY

        DROP CELL

        DROP CELLDISK

        DROP FLASHCACHE

        DROP GRIDDISK
        DROP QUARANTINE

        DROP THRESHOLD

        EXPORT CELLDISK

        IMPORT CELLDISK

        LIST

        LIST ACTIVEREQUEST

        LIST ALERTDEFINITION

        LIST ALERTHISTORY

        LIST CELL

        LIST CELLDISK

        LIST FLASHCACHE

        LIST FLASHCACHECONTENT
        LIST GRIDDISK

        LIST IBPORT
        LIST IORMPLAN

        LIST KEY

        LIST LUN

        LIST METRICCURRENT

        LIST METRICDEFINITION

        LIST METRICHISTORY

        LIST PHYSICALDISK
        LIST QUARANTINE

        LIST THRESHOLD

        SET

        SPOOL

        START