Functional Overview of the NXA-SFAN-35CFM-PI= Module
The NXA-SFAN-35CFM-PI= is a hot-swappable, 35 CFM (cubic feet per minute) airflow fan tray engineered for Cisco Nexus 9500 and 9300 Series switches. Designed for high-density data center environments, this module ensures ASIC thermal management within Cisco’s strict 55°C operational threshold while reducing acoustic noise to 48dB(A). Its dual-rotor design supports N+1 redundancy, critical for maintaining uptime in hyperscale and financial trading infrastructures.
Hardware Specifications and Environmental Tolerance
2.1 Mechanical Design and Airflow Efficiency
- Dual Counter-Rotating Fans: Mitigate harmonic resonance, enabling 92% airflow consistency even at 95% PWM (pulse-width modulation) duty cycles.
- Power Draw: 180W max (48VDC input), with Smart Power Budgeting to prioritize cooling for line cards running 400G ZR optics.
- Operating Conditions: Functions at full capacity in -5°C to 55°C ambient temperatures and 5–95% non-condensing humidity.
2.2 Acoustic Performance Metrics
Unlike traditional single-rotor fans, the NXA-SFAN-35CFM-PI= reduces noise pollution through:
- Isolated Vibration Pads: Absorb 80% of high-frequency (4–8kHz) vibrations.
- Variable Speed Control: Auto-adjusts RPM based on real-time thermal sensors, maintaining noise below 50dB(A) during 70% load.
Deployment Scenarios and Compatibility
3.1 Nexus 9508/9516 Chassis Integration
When installed in a Nexus 9508 chassis, the fan module:
- Supports front-to-back (F2B) and back-to-front (B2F) airflow configurations via software-defined polarity reversal.
- Synchronizes with NXA-PAC-650W-PI= power supplies to balance cooling and power efficiency.
3.2 High-Density 400G Deployments
For environments using 400G QSFP-DD transceivers, the NXA-SFAN-35CFM-PI= prevents thermal throttling by:
- Zone-Based Cooling: Allocates 60% airflow to slots running Cisco QSFP-400G-ZR-S optics.
- Predictive Failure Analysis: Flags bearing wear via S.M.A.R.T. diagnostics 72+ hours before fan RPM degradation.
Operational Best Practices and Troubleshooting
4.1 Redundancy Configuration Guidelines
- N+1 Mode: Requires 5 fan modules for a 4+1 setup in Nexus 9500 chassis. A single failure triggers 10% over-speed in adjacent fans to compensate.
- Graceful Shutdown: If two fans fail, the system throttles non-critical ports (e.g., management interfaces) to reduce heat generation.
4.2 Common Failure Modes and Mitigations
- Dust Ingress: Deploy MERV 14-rated air filters in facilities with >500μg/m³ particulate levels.
- PWM Signal Loss: Use Cisco Crosswork Network Automation to reroute PWM control to secondary supervisor engines.
Case Study: Tier-4 Data Center Implementation
A Frankfurt-based colocation provider replaced legacy NXA-FAN-30CFM modules with NXA-SFAN-35CFM-PI= across 120 Nexus 9336C-FX2 switches, achieving:
Metric |
Legacy Fans |
NXA-SFAN-35CFM-PI= |
ASIC Temperature |
63°C |
51°C |
Fan-Related Downtime |
14hr/year |
0.8hr/year |
Energy Consumption |
210W/unit |
167W/unit |
Procurement and Supply Chain Considerations
Cisco’s Enhanced Limited Lifetime Warranty covers the NXA-SFAN-35CFM-PI= for 10 years, but excludes physical damage from improper airflow alignment. For urgent replacements, [“NXA-SFAN-35CFM-PI=” link to (https://itmall.sale/product-category/cisco/) provides same-day shipping with firmware pre-validation to avoid NX-OS compatibility issues.
Cost-Benefit Analysis and ROI
- Energy Savings: 23% reduction in cooling overhead per rack (calculated using Cisco’s DC Cost Calculator).
- MTTR Reduction: Hot-swap capability cuts mean time-to-repair by 83% compared to fixed fan trays.
- Compliance: Meets ASHRAE TC 9.9 Class H3 standards for hyperscale data centers.
Final Observations: The Role of Adaptive Cooling in Modern DCs
While the NXA-SFAN-35CFM-PI= sets a benchmark for reliability, its effectiveness hinges on proper rack layout design. In my experience, operators often overlook negative pressure zones created by mixed F2B/B2F configurations, forcing fans to work 20–30% harder. Pairing this module with blanking panels and CFD modeling tools like Future Facilities’ 6SigmaDCX resolves most issues.
Looking ahead, emerging liquid-cooling retrofits may challenge air-cooled dominance, but for brownfield facilities, the NXA-SFAN-35CFM-PI= remains the safest bet to extend Nexus 9000 lifespans until 2030. Just ensure your facility team audits fan bearings annually—proactive maintenance beats reactive firefighting every time.