Compaq AlphaServer ES45 1B Owner's Manual page 209

Examples
In the following example, the operator sets the auto_action environment vari-
able to restart. The device specified with the bootdef_dev environment vari-
able is dka0. When Tru64 UNIX is shut down and rebooted, the system will
reboot from dka0.
P00>>> show auto_action
auto_action
P00>>> set auto_action restart
P00>>> init
.
.
.
P00>>> show auto_action
auto_action
P00>>> show bootdef_dev
bootdef_dev
P00>>> boot
...
(Log into UNIX and shutdown/reboot)
#shutdown -r now
...
console will boot from dka0
In the following example, auto_action is set to restart, but Tru64 UNIX is
booted from a device other than the device set with bootdef_dev. When UNIX
is shut down and rebooted, the system reboots from the specified device.
P00>>> boot dka100
.
.
.
(Log into UNIX and shutdown/reboot)
#shutdown -r now
...
console will boot from dka100
halt
restart
dka0
Firmware 5-45