DEC AlphaServer 1000A Owner's Manual page 66

Changing Startup and Boot Defaults
You can change the way the system starts up or boots the operating system. For
example, you can set the system to autoboot or you can change the default boot
device. To make these kinds of changes you need to change default values for your
system's environment variables.
To change default values for Windows NT systems, which boot automatically,
you can prevent autoboot by selecting one of the menu options.
To change default values for Digital UNIX or OpenVMS Alpha systems, see
"set" in Table 4-1, "Basic SRM Console Commands."
Startup and Boot Environment Variables
The following environment variables affect the way the system starts up or boots:
auto_action
autoload
countdown
os_type
Table 4-3 lists the boot environment variables and their values, and briefly describes
their effects. Environment variables marked with an asterisk * in Table 4-3 require
that you use the init command to initialize the firmware whenever you reset that
particular variable. Example: >>> set os_type NT
4-20 Basic Operation
>>> init
AlphaServer 1000A Owner's Guide