System Fan Configuration Rules - Sun Microsystems Sun Fire V445 Server Administration Manual

The environmental subsystem monitors all fans in the system, and prints a warning
and lights the system Service Required indicator if any fan falls below its nominal
operating speed. This provides an early warning to an impending fan failure,
enabling you to schedule downtime for replacement before an overtemperature
condition shuts down the system unexpectedly.
For a fan failure, the following indicators are lit:
Front panel:
Service Required (amber)
Operating (green)
Fan failure (amber)
CPU over temperature (if the system is overheating)
Top panel:
Specific fan failure (amber)
All other fans (green)
Back panel:
Service Required (amber)
Running (green)
In addition, the environmental subsystem prints a warning and lights the system
Service Required indicator if internal temperature rises above a predetermined
threshold, either due to fan failure or external environmental conditions. For
additional details, see

System Fan Configuration Rules

The minimum system configuration requires at least one fan operating per
redundant pair.
Note – For instructions on how to remove and install fan trays, refer to the Sun Fire
V445 Server Service Manual.
94 Sun Fire V445 Server Administration Guide • September 2007
Chapter 8.