• If your rack includes closing front and rear doors, the doors must have 65 percent open perforated area
evenly distributed from top to bottom to permit adequate airflow.
• Be sure enclosed racks have adequate ventilation. Make sure that the rack is not overly congested as each
chassis generates heat. An enclosed rack should have louvered sides and a fan to provide cooling air.
• In an enclosed rack with a ventilation fan in the top, heat generated by equipment near the bottom of the
rack can be drawn upward and into the intake ports of the equipment above it in the rack. Ensure that
you provide adequate ventilation for equipment at the bottom of the rack.
• Baffles can help to isolate exhaust air from intake air, which also helps to draw cooling air through the
chassis. The best placement of the baffles depends on the airflow patterns in the rack. Experiment with
different arrangements to position the baffles effectively.
Cisco Firepower 1100 Series Hardware Installation Guide
25
Installation Preparation
Rack Configuration Considerations