Cisco N6K-C6004-FAN-F= rack cooling equipment

The Cisco Nexus 6004 switch has four fan modules. Although the switch can function when a fan stops functioning within a fan module, if a whole fan module stops functioning, you must replace the fan module. The Cisco Nexus 6004 switch supports the front to back airflow (N6K-C6004-FAN-F) and back to front airflow (N6K-C6004-FAN-B).