How to enable Exadata writeback Flashcache on cell storage ? (WriteThrough to WriteBack)

Steps to enabling the Flashcache mode:

This can be done in rolling as well as non-rolloing manner.

First check flashcache mode with below command on all cell servers with the use of dcli utility on DB node. It can be check on cell each server also with cellcli utility.

dbnode1#dcli -l root -g cellgroup "cellcli -e list cell detail" | grep "flashCacheMode"

10.156.110.10: flashCacheMode:          WriteThrough
10.156.110.11: flashCacheMode:          WriteThrough
10.156.110.12: flashCacheMode:          WriteThrough
10.156.110.13: flashCacheMode:          WriteThrough
10.156.110.14: flashCacheMode:          WriteThrough
10.156.110.15: flashCacheMode:          WriteThrough
10.156.110.16: flashCacheMode:          WriteThrough

Step-1
Also we can find flashcache mode in each cell by executing below command:

cellcli>list cell detail

flashCacheMode: WriteThrough     --->Currently flashCacheMode configured as WriteThrough

Step-2
Now drop flashcache on each cell server: (If you are following rolling manner then do one by one on each cell server)

cellcli> drop flashcache

Step-3
Be sure asmdeactivationoutcome is YES before disabling grid disk

CellCLI> list griddisk attributes name,asmmodestatus,asmdeactivationoutcome

Step-4