Sounds like a BIOS Password prompt, correct?
I do not know of any way to set soemthing like this on a NetApp Controller.
One possible workaround could be to prevent it from automatic starting up. I'm not sure if this environment variable still is valid with todays ontap versions (especially Ontap 8).
try setting this FW env variable to TRUE:
CFE> setenv floppy-boot? true
check with thi scomand if it took the setting:
CFE> printenv floppy-boot?
This will make the controller to start and then wait after the FW load for an answer to the question:
Floppy Boot (Y/N)
...........
Maybe this helps,
Peter