Juniper QFX5120 Series Hardware Manual page 34

CAUTION:
inside the chassis rises above the acceptable range. If the temperature inside the chassis
rises above the threshold temperature, the system shuts down automatically.
Positioning the Switch
In a switch with front-to-back airflow, indicated by the label AIR OUT (AFO) on the fan modules and power
supplies, hot air exhausts through the vents on the rear panel of the switch. In a switch with back-to-front
airflow, indicated by the label AIR IN (AFI) on the fan modules and power supplies, hot air exhausts through
the vents on the front panel of the switch.
In data center deployments, position the switch in such a manner that the AIR IN (AFI) labels on the switch
components are next to the cold aisle, and the AIR OUT (AFO) labels on the switch components are next
to the hot aisle.
QFX5120 Fan Module Status
A QFX5120 switch has a status LED for each fan module next to the fan module slot on the rear panel of
the chassis. The status LED indicates the status of the fan module.
LED on the fan module of a QFX5120 switch.
Table 7: Fan Module Status LED
LED Color
Status Green
Amber
Under normal operating conditions, the fan modules operate at a moderate speed. Temperature sensors
in the chassis monitor the temperature within the chassis.
CAUTION:
inside the chassis rises above the acceptable range. If the temperature inside the chassis
rises above the threshold temperature, the system shuts down automatically.
The system raises an alarm if a fan module fails or if the ambient temperature
State
On steadily
Blinking
The system raises an alarm if a fan module fails or if the ambient temperature
Table 7 on page 36
Description
The fan module is functioning normally.
An error has been detected in the fan module. Either the fan
has failed or it is seated incorrectly. Replace the fan module as
soon as possible. To maintain proper airflow through the
chassis, leave the fan module installed in the chassis until you
are ready to replace it.
describes the status
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