Sun Microsystems Sun Ultra 450, Manual

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Environmental Monitoring and Control
Environmental monitoring and control capabilities for an Ultra 450 system reside at
both the operating system level and the OBP firmware level. This ensures that
monitoring capabilities are operational even if the system has halted or is unable to
boot. The way in which OBP monitors and reacts to environmental over temperature
conditions is controlled by the NVRAM variable
env-monitor
. The following table
shows the various settings for this variable and the effect each setting has on OBP
behavior. For additional information about the system’s environmental monitoring
capabilities, see “About Reliability, Availability, and Serviceability Features” in the
owner’s guide provided with your Ultra 450 system.
TABLE 2–4
Settings for the
env-monitor
Variable
Setting
Monitor
Active?
Action Taken
enabled
(default)
Yes In response to an over temperature condition or a fan
failure in either the CPU or disk fan tray, OBP issues a
warning and automatically shuts down the system
after 30 seconds.
advise
Yes OBP issues a warning only, without shutting down
the system.
disabled
No OBP takes no action at all; environmental monitoring
at the OBP level is disabled.
In the following example, the
env-monitor
variable is used to disable
environmental monitoring at the OBP level.
ok setenv env-monitor disabled
Note - This NVRAM variable does not affect the system’s environmental monitoring
and control capabilities while the operating system is running.
System Configuration Parameters
9