To access the preboot menu, you must boot the SP and interrupt the boot process.
There are two ways to interrupt the ILOM boot process: manually using the Locate button, or by typing xyzzy during a pause in the bootstrap process.
The first method requires you to have physical access to the server module. The second method can be done remotely. However:
You must use a terminal or a terminal emulator. You cannot use an SSH, or an RKVMS session.
Some preboot menu settings must be configured first, and until they are, you must use the Locate button.
Because the settings must be configured before you can access the preboot menu remotely, the first time you access the preboot menu, you must use the locate button to access the preboot menu, and configure the settings. This is described in Using the edit Command and Configuring the Preboot Menu For Remote Access.