The Firepower 4100 requires six fan modules, which are hot-swappable. They are installed in the rear of the chassis. The system supports operation with a single fan failure (N+1 fan redundancy), but do not run the system for an extended amount of time without all fan modules installed. Keep removal and replacement time at three minutes. Remove and replace one fan module at a time.

If you remove a fan or a fan fails, the other fans operate at full speed, which can be noisy.

The fan modules are numbered left to right, for example, FAN1, FAN2, FAN3, FAN4, FAN5, and FAN6. See Remove and Replace the Fan Module for the procedure for removing and replacing the fan module.

The following figure shows the location of the fan LED.

1

Two-color LED

The fan module has one two-color LED, which is located on the upper left corner of the fan.

Amber—Fan failure.

Green—Fan running normally. It may take up to one minute for the LED status to turn green after power is on.