18 Sun Fire V890 Server Owner’s Guide • September 2004
Thermal Monitoring
Temperature sensors are located throughout the system to monitor the ambient
temperature of the system and the temperature of each processor. The monitoring
subsystem frequently polls each sensor and uses the sampled temperatures to report
and to respond to any overtemperature or undertemperature conditions.
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.
Fan Monitoring
The monitoring subsystem is also designed to detect fan failures. The system
features three primary fan trays, which include a total of five individual fans, plus
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
Power Subsystem Monitoring
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.
To Next Page
Loading...
Need help?
General
