Dell N1100-ON, Reference Manual

Page: 2227 / 2332

Switch Management Commands
2227
Command Mode
User Exec mode, Privileged Exec mode, Global Configuration mode and all
Configuration submodes
User Guidelines
The system temperature is read from one or more sensors placed at critical
locations on the PCB. Status ranges are subdivided into Good (Cool),
Medium (Warm), and High (Hot). Each status range has a lower, mid-range,
and upper limit with the upper limit of the lower temperature status being
the same as the lower limit of the adjacent higher temperature status. Within
a range, the fans run at a reduced speed for the lower temperature part of the
range and an increased speed for the higher temperature part of the range.
Each range runs the fans at increasingly higher speeds for increasingly higher
temperatures. Above the High status upper limit, the system is shut down.
Typically, the shutoff temperature for the switch is 90-105<Variable>°C.
To avoid fan speed oscillation around a temperature limit, a small hysteresis is
added to the limit such that the temperature for increasing the fan speed is
higher than the temperature for lowering the fan speed. This implies that the
higher fan speed (and status) is maintained until the switch is cooled 3-5
degrees below the threshold for increasing the fan speed (and possibly
changing the status). The exact thresholds for increasing or lowering the fan
speed are determined during thermal analysis and are different for each
switch family.
Examples
console#show system temperature
System Thermal Conditions:
Unit Temperature State
(Celsius)
---- ----------- -----------
1 34 Good
Temperature Sensors:
Unit Description Temperature
(Celsius)
---- ------------------ -----------
1 MAC 33