QFX5130 Cooling System

QFX5130 Cooling System Description

The cooling system in a QFX5130 consists of six fan modules and a single fan in each power supply. The switch can ordered in one of two airflow directions:

Airflow In (AFI)—Air comes into the switch through the vents in the field-replaceable units (FRUs).
Airflow Out (AFO)—Air comes into the switch through the vents in the port panel.

CAUTION:

Airflow In and Airflow Out fans and power supplies cannot be mixed in the same chassis.

Fan Modules
Do Not Install Components with Different Airflow or Wattage in the Switch

Fan Modules

The fan modules in QFX5130 devices are hot-insertable and hot-removable field-replaceable units (FRUs). These fan modules are designed for one of the two available airflow directions (AFI or AFO). The fan modules are color-coded for the airflow direction as well. The fan modules are installed in the fan module slots on the FRU panel.

The QFX5130-32CD and QFX5130-48C cooling system consists of six fan modules numbered 0 through 5 when counting from left to right.

Figure 1 shows the fan module for QFX5130-32CD.

Figure 1: QFX5130-32CD Fan Module

You remove and replace a fan module from the FRU end of the chassis. The QFX5130-32CD switch can work with only five fans. However, we recommend that you run the switch with all six fans for redundancy and optimal switch operation. If a fan fails, or you want to run the switch without redundancy, leave the sixth fan in place to maintain proper airflow. When you replace a fan, the switch continues to operate for a limited period of time (3 minutes) without thermal alarms or shutdown.

Figure 2 shows the fan module for QFX5130-48C.

Figure 2: QFX5130-48C Fan Module

You remove and replace a fan module from the FRU end of the chassis. The QFX5130-48C switch cannot work with only five fans as the redundancy for QFX5130 48C is supported only at the rotor level. We recommend that you run with all six fans for redundancy and optimal operation of the switch. If a fan rotor fails, or if you want to run the switch without redundancy, you would need to leave the sixth fan in place in order to maintain proper airflow. When you replace a fan, the switch continues to operate for a limited period of time (240 seconds) without thermal alarms or shutdown.

The fan modules are available in two product variants that have different airflow directions—FRU-to-port airflow and port-to-FRU airflow. Table 1 lists the available fan module product variants and the direction of airflow in them:

Table 1: Fan Modules in QFX5130 Switches
Fan Module	Airflow Diagram	Label on the Fan Module	Color of Fan Module	Direction of Airflow in the Fan Module	Power Supplies
QFX5130-32CD-FANAI	Figure 3	AIR IN	Juniper azure blue	FRU-to-port, that is, air comes in from the end of the switch with the fans; air exhausts from the switch end with ports (also known as back-to-front airflow).	You must install only those power supplies that have AIR IN labels in switches in which the fan modules have AIR IN labels.
QFX5130-32CD-FANAO	Figure 5	AIR OUT	Juniper gold	Port-to-FRU, that is, air comes in through vents on the end with ports; air exhausts out the end with the fans (also known as front-to-back airflow).	You must install only power supplies that have AIR OUT labels in switches in which the fan modules have AIR OUT labels.
QFX5130-48C-FANAFI	Figure 4	AIR IN	Juniper azure blue	FRU-to-port, that is, air comes in from the end of the switch with the fans; air exhausts from the switch end with ports (also known as back-to-front airflow).	You must install only power supplies that have AIR IN labels in switches in which the fan modules have AIR IN labels.
QFX5130-48C-FANAFO	Figure 6	AIR OUT	Juniper gold	Port-to-FRU, that is, air comes in through vents on the end with ports; air exhausts out the end with the fans (also known as front-to-back airflow).	You must install only power supplies that have AIR OUT labels in switches in which the fan modules have AIR OUT labels.

In data center deployments, position the switch in such a manner that the AIR IN labels on switch components are next to the cold aisle and AIR OUT labels on the switch components are next to the hot aisle.

Figure 3: Air-In Airflow Through QFX5130-32CD Air-In Airflow Through QFX5130-32CD

Figure 4: Air-In Airflow through QFX5130-48C

Figure 5: Air-Out Airflow Through QFX5130-32CD Air-Out Airflow Through QFX5130-32CD

Figure 6: Air-Out Airflow Through QFX5130-48C Air-Out Airflow Through QFX5130-48C

Do Not Install Components with Different Airflow or Wattage in the Switch

Do not mix airflow direction on fans or power supplies. You can use the color-coding on fan and power supply handles to ensure that the airflow direction matches. The handles on AFI fans and power supplies are azure blue, compared to the AFO fans and power supplies, which are Juniper gold.

Mixing components with different airflows in the same chassis hampers the performance of the cooling system of the switch and leads to overheating of the chassis.

CAUTION:

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. The system takes 3 minutes (for QFX5130-32CD) or 240 seconds (for QFX5130-48C) to shut down after the red alarm threshold is reached.

Do not mix fan modules with different wattage. Use only the replacement fan modules that are designed for use with your product number. See Table 1 for the correct part number for your QFX5130 switch.

CAUTION:

Do not mix AC and DC power supplies in the same QFX5130 chassis.

However, if you need to convert a QFX5130 switch to have a different airflow, you can change the airflow pattern. To convert an AIR IN product variant to an AIR OUT product variant or an AIR OUT product variant to an AIR IN product variant, you must power off and replace all of the fans and power supplies at one time to use the new airflow direction. The system raises an alarm when the system is converted, which is normal.

Note:

If you change the switch to have a different airflow, be sure to update your JTAC install base to reflect the new configuration to ensure that service warranties and contracts remain˙.

QFX5130 Fan Module LED

On the QFX5130-32CD switches, the fan module LEDs are located on the chassis, next to the fan module slot. On the QFX5130-48C switches, the fan module LEDs are located on the fan module. Figure 7 shows the location of fan module LEDs next to the fan module on a QFX5130-32CD switch.Figure 8 shows the location of fan module LEDs on a QFX5130-48C switch.

Figure 7: Fan Module LEDs on a QFX5130-32CD

1

—

Fan module LED

Figure 8: Fan Module LEDs on a QFX5130-48C

1

—

Fan module LED

Note:

The fans are numbered 0 through 5, starting from the fan closest to the ports.

Table 2 describes the function of the fan tray LED.

Table 2: Fan Tray LED Behavior in a QFX5130 Switch
Name	Color	State	Description
Fan	Green	On steadily	The fan module is operating normally. The system has verified that the module is engaged, that the airflow is in the correct direction, and that the fan is operating correctly.
	Amber (QFX5130-32CD)	Blinking	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.
	Amber (QFX5130-48C)	On steadily	Indicates one of the following conditions: 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.

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.

Fan Module Status

You can check the status of fan modules by issuing the show chassis temperature-thresholds, show system alarm, or show chassis environment commands, or by looking at the LEDs next to each fan module. On the QFX5130-48C switches, the LED is located on the fan module. For example:

The QFX5130 switch has a status LED (labeled ST) for each fan module. The LED indicates the status of all the fan modules.

ON THIS PAGE