Sun Microsystems Fire 880, Руководство пользователя

Страница: 35 / 236

Chapter 1 System Overview 17
The hardware and software together ensure that the temperatures within the
enclosure do not stray outside predetermined “safe operation” ranges. If the
temperature observed by a sensor falls below a low-temperature warning threshold
or rises above a high-temperature warning threshold, the monitoring subsystem
software generates a WARNING message to the system console. If the temperature
exceeds a low- or high-temperature critical threshold, the software will issue a
CRITICAL message and proceed to gracefully shut down the system. In both cases,
the System Fault and Thermal Fault LEDs on the front status panel are illuminated
to indicate the nature of the problem.
This thermal shutdown capability is also built into the hardware circuitry as a
fail-safe measure. This feature provides backup thermal protection in the unlikely
event that the environmental monitoring subsystem becomes disabled at both the
software and firmware levels.
All error and warning messages are displayed on the system console (if one is
attached) and are logged in the
/var/adm/messages
file. Front panel fault LEDs
remain lit after an automatic system shutdown to aid in problem diagnosis.
The monitoring subsystem is also designed to detect fan failures. The basic system
features three primary fan trays, which include a total of five individual fans.
Systems equipped with the redundant cooling option include three additional
(secondary) fan trays for a total of 10 individual fans. During normal operation, only
the five primary fans are active. If any fan fails, the monitoring subsystem detects
the failure and:
■
Generates an error message and logs it in the
/var/adm/messages
file
■
Lights the System Fault and Thermal Fault LEDs on the status and control panel
■
Lights the appropriate fan fault LED inside the system
■
Automatically activates the appropriate secondary fan tray (if installed)
The power subsystem is monitored in a similar fashion. The monitoring subsystem
periodically polls the power supply status registers for a power supply OK status,
indicating the status of each supply’s 3.3V, 5.0V, 12V, and 48V DC outputs.
If a power supply problem is detected, an error message is displayed on the system
console and logged in the
/var/adm/messages
file. The System Fault and Power
Fault LEDs on the status and control panel are also lit. LEDs located on the back of
each power supply will indicate the source and nature of the fault.
For more information about error messages generated by the environmental
monitoring subsystem, see the
Sun Fire 880 Server Service Manual . For more
information about system LEDs, see Chapter 8.