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QFX10002 Cooling System

QFX10002 Cooling System and Airflow

The cooling system in a QFX10002 consists of three 80-W fan modules in a fan tray and two counter-rotating fans housed in each of the power supplies.

The QFX10002 brings air into the vents in the port panel and exhausts warmed air through the field-replaceable units (FRU) panel. This type of airflow is known as airflow out or port-to-FRU airflow.

This topic describes:

Fan Modules

The fan modules in a QFX10002 are hot-removable and hot-insertable FRUs designed for port-to-FRU airflow. The fan modules numbered 0 through 2 are installed in the fan tray located next to the power supplies. Each fan module slot has a fan icon next to it.

Figure 1 shows the 2-U fan module for the QFX10002 models.

Figure 1: Fan Module for the QFX10002Fan Module for the QFX10002

You remove and replace a fan module from the FRU end of the chassis. The switch continues to operate for a limited period of time (30 seconds) during the replacement of the fan module without thermal shutdown.


All fan modules must be installed for optimal operation of the switch.

Table 1 lists the fan module details.

Table 1: Fan Modules in the QFX10002

Fan Module

Airflow Diagram

Label on the Fan Module

Color of Fan Module Handle

Direction of Airflow in the Fan Module

Power Supplies


Figure 2


Juniper Gold

Port-to-FRU airflow is where air enters on the end with the ports and exits on the end with fans (also known as airflow out).

All models only use power supplies that have gold-colored handles with AIR OUT labels.

In data center deployments, position the switch in such a manner that the AIR OUT labels on switch components are next to the hot aisle. Figure 2 shows the airflow through the chassis.

Figure 2: Air Out Airflow Through the QFX10002 ChassisAir Out Airflow Through the QFX10002 Chassis

Fan Module Status

You can check the status of fan modules through the show system alarms command or show chassis fan commands or by looking at the LEDs next to each fan module. For example:

Each switch has a status LED (labeled ST) for each fan module on the left side of the corresponding fan module slot. It indicates the status of all the fan modules. Table 2 describes the status LED on the fan module in a QFX10002.

Table 2: Fan Module Status LED

LED State


Solid Green

Indicates the individual fan module is present. After the hardware senses the fan module, software ensures the airflow is consistent with the other fan modules and that it is functioning correctly.

Solid Amber

Indicates one of the following:

  • The fan module is not present.

  • The fan module is not functioning normally.

Under normal operating conditions, the fan modules operate at a moderate speed. Temperature sensors in the chassis monitor the temperature within the chassis.

The system raises an alarm if a fan module fails or if the ambient temperature inside the chassis rises above the acceptable range. If the temperature inside the chassis rises above the threshold temperature, the system shuts down automatically.

QFX10002 Fan Module LED

Figure 3 shows the location of the LED next to the QFX10002 fan module.

Figure 3: Fan Module LED in a QFX10002Fan Module LED in a QFX10002



Use Table 3 to interpret the state of the fan module LED.

Table 3: QFX10002 Fan Module LED







On steadily

The fan module is operating normally. The system has verified that the module is engaged, and that the fan is operating correctly.


On steadily

An error has been detected in the fan module. Replace the fan module as soon as possible. Either the fan has failed or it is seated incorrectly. To maintain proper airflow through the chassis, leave the fan module installed in the chassis until you are ready to replace it.