Fan Modules in a QFX3100 Director Device
Fan modules provide cooling to a QFX3100 Director device. All QFX3100 Director devices are shipped with three fan modules installed in the fan module slots on the rear panel of the chassis. See Figure 1.

A QFX3100 Director device can operate for a short time with a fan module removed; however, the chassis might shut down when the high temperature threshold is exceeded if a fan module is not available to cool the QFX3100 Director device properly.
Fan modules are hot-swappable and field-replaceable units (FRUs).