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C H A P T E R
4
OpenBoot PROM Features
This chapter describes some OpenBoot PROM features and procedures.
OpenBoot
ok
Prompt
Oracle’s Sun Blade T6340 server module with the Solaris OS installed operates at
different
run levels
. For a full description of run levels, refer to the Solaris system
administration documentation.
Most of the time, you operate the server module at run level 2 or run level 3, which
are multiuser states with access to full system and network resources. Occasionally,
you might operate the system at run level 1, which is a single-user administrative
state. However, the lowest operational state is run level 0. At this state, it is safe to
turn off power to the system.
When the server module is at run level 0, the
ok
prompt appears. This prompt
indicates that the OpenBoot firmware is in control of the system.
There are a number of scenarios under which OpenBoot firmware control can occur:
■
By default, before the operating system is installed the system comes up under
OpenBoot firmware control.
■
When the
auto-boot?
OpenBoot configuration variable is set to
false
, the
system boots to the
ok
prompt.
■
After the Solaris OS is halted, the system transitions to run level 0 in an orderly
way.
■
During the boot process, when there is a serious hardware problem that prevents
the operating system from running, the system reverts to OpenBoot firmware
control.
■
When you deliberately place the system under firmware control in order to
execute firmware-based commands, you have the
ok
prompt.
