To reset nvram if for some reason you can’t get to the console or run eeprom from the OS
1. Press the power button to power up the system.
2. Once the maintenance LED starts to flash rapidly, immediately press the Power button twice (similar to double-clicking a mouse, but leave a short gap of around 1 second between presses, to have the action reliably registered.) The actual time when you do the double press of the power button is the point in POST when the maintenance LED (wrench light) rapidly flashes.
If you double press too late or too soon, the system will power off. Do not get confused with the earlier occurrences of the maintenance and OK to remove LEDs flashing together. This is a part of the system test to make sure the LEDs are functional.
If you’re running POST even in MIN level, it will be several minutes depending upon your configuration, before the maintenance LED flashes rapidly.
A screen similar to the following is displayed to indicate that you have successfully reset the OpenBoot NVRAM configuration variables to their default values:
Sun Fire xxx (8 X UltraSPARC-III), Keyboard Present
OpenBoot x.x, 256 MB memory installed, Serial #xxxxxxxx.
Ethernet address xx:xx:xx:xx:xx:xx, Host ID: xxxxxxxx.
Safe NVRAM mode, the following nvram configuration variables have been
diag-switch? is true
use-nvramrc? is false
input-device , output-device are defaulted
ttya-mode , ttyb-mode are defaulted
These changes are temporary and the original values will be restored after the next hardware or software reset. Once you are at the OK prompt, it is at this point you make your changes to the OBP parameters, or use set-defaults to reset all parameters to factory default settings.