For devices that support pluggable fan modules, how to solve the problem that the SYS light is always red after booting?

For devices that support pluggable fan modules, if the fan module is normal, but the actual air duct wind direction of the fan module is inconsistent with the air duct wind direction of the fan module expected by the device, the device system indicator light (SYS light) is abnormal (red is always on), but the indicator light of the fan module is normal (yellow is always on). At this time, the fan operation noise is usually relatively large, and the device will print the log information of the fan alarm.

The actual air duct direction of the fan module is determined by the model of the selected fan module. Usually there are: port side air inlet, power side air outlet or power side air inlet, and port side air outlet. You can check the corresponding fan manual to understand; you can also check the field “Airflow Direction” (the actual air duct direction of the fan module) by executing the display fan command on the device.

The desired air duct direction of the fan module of the device can be configured through the command line, and can be understood by executing the display fan command and viewing the field “Preferred Airflow Direction” (the desired air duct direction of the fan module).

< Sysname > display fan

Slot 1:

Fan 1:

State: Normal

Airflow Direction: Port-to-power

Preferred Airflow Direction: Port-to-power

When the two are inconsistent, the desired air duct direction of the device can be adjusted through the fan advance-direction command in the system view to make it consistent with the actual air duct direction of the fan module.

· Specify the parameter port-to-power, indicating that the desired air duct direction is the air inlet on the port side and the air outlet on the power side.

· Specify the parameter power-to-port, indicating that the desired air duct direction is the inlet air on the power side and the outlet air on the port side.

It should be noted that after the device is powered on, whether to check the actual air duct wind direction of the fan module is consistent with the air duct wind direction of the fan module expected by the device is related to the product and software version. Please refer to the installation instructions for the specific situation of each product.