I have recently replaced a flash disk in one of the cell of Exadata X6-2 which was synced and all activated/online.
We faced an issue for BBU on Cell05 but the same time it was showing some false error "partner disk was not online cell04"
Now I could see the MS and cellsrv services are stopped and could not be started with error:
CELL-02018: Internal error detected: Disk discovery failed.
there are lots of document for the error CELL-02018: Internal error detected: xxx. but coudnot find any for Disk discovery failed.
I have rebooted the cellnode. BBU capacitor not yet replaced.