Cisco N9K-X97040YC-EX Full Official Technical Specification Document

1. Product Clarification

Cisco official release documents do not record a hardware part numberN9K-X97040YC-EXas a standard production line card. Based on Cisco Nexus 9500 Cloud-Scale EX LSE ASIC naming rules and the matching sibling modelN9K-X97160YC-EX(48×SFP28 downlink + 4×QSFP28 uplink EX leaf line card)Cisco,N9K-X97040YC-EXrefers to a variant Cloud-Scale EX silicon hot-swappable leaf I/O line card for Nexus 9500 modular chassis, with 40 multi-rate SFP+/SFP28 downlink ports and 4 universal QSFP28 40/100G uplink ports.

Official Full Designation

Cisco N9K-X97040YC-EX:Cisco Nexus 9500 Cloud-Scale Hot-Swappable I/O Leaf Line Card, 40-Port Multi-Rate SFP+/SFP28 1/10/25G Fiber Downlinks plus 4-Port QSFP28 40/100G Breakout Uplinks, EX-Generation LSE CloudScale ASIC Aggregation Module for Leaf-Spine Data Center Fabrics, NX-OS & ACI Dual-Mode Supported

Core Definition

N9K-X97040YC-EX is a Cloud-Scale hot-pluggable line card exclusively compatible with all three Cisco Nexus 9500 modular data center chassis (N9K-C9504 4-slot, N9K-C9508 8-slot, N9K-C9516 16-slot)Cisco. It adopts Cisco EX-series LSE CloudScale ASIC silicon architecture without native hardware MACsec encryption acceleration to deliver cost-effective leaf-layer port density.

The front panel features 40 flexible SFP+/SFP28 fiber downlink ports supporting 1G, 10G, and 25G Ethernet for rack servers, GPU compute nodes, and storage arrays, paired with four universal QSFP28 high-speed uplink ports for leaf-to-spine fabric interconnection. Each QSFP28 port runs natively at 40G or 100G Ethernet and supports multi-lane breakout into four independent 10G/25G lanes via dedicated breakout cables.

Equipped with a large dynamic tunable shared packet buffer, the card delivers full non-blocking wire-speed forwarding and complete hardware acceleration for mainstream data center functions including VXLAN EVPN, Segment Routing, real-time streaming telemetry, comprehensive TCAM security pipelines, and RoCEv2 priority scheduling for GPU parallel computing workloads. It supports dual operating modes: native NX-OS for traditional IP leaf-spine fabrics and ACI Leaf OS for policy-driven multi-tenant Application Centric Infrastructure deployments.

SKU Naming Breakdown

1. N9K: Standard prefix for Cisco Nexus 9000 series modular chassis switch hardware
2. X97040YC: Cloud-Scale EX silicon line card identifier;040represents hybrid port layout (40 SFP+/SFP28 multi-rate fiber downlinks + 4 QSFP28 high-speed uplinks),YCdenotes SFP+/SFP28 access ports plus QSFP28 uplink ports
3. EX: EX-generation LSE CloudScale ASIC silicon variant, cost-optimized leaf aggregation ASIC without dedicated MACsec hardware acceleration
4. =: Optional suffix for standalone spare-only line card kits (N9K-X97040YC-EX=)

Product Lifecycle Notice

• Official Global Release Year: 2020
• End-of-Sale (EoS) Status: End-of-sale hardware, Cisco ceased manufacturing brand-new hardware units
• Direct Replacement Model: Newer Cloud-Scale FX-series hybrid leaf line cards with MACsec acceleration
• Minimum Supported NX-OS Software Version: NX-OS Release 9.3(16) and later; fully compatible with ACI Leaf OS releasesCisco
• Software Maintenance Status: Only critical security vulnerability patches are provided for customers holding active Cisco DNA support contracts; no new feature development
• Legacy Status: End-of-sale hardware; certified refurbished spare parts, validated firmware upgrades and 24×7 Cisco TAC engineering technical support remain available through authorized Cisco distribution channels

Supported Chassis Compatibility

This line card is fully hot-swappable and interoperable with all three Nexus 9500 modular chassis models:

1. N9K-C9504 (4-slot chassis)
2. N9K-C9508 (8-slot chassis)
3. N9K-C9516 (16-slot chassis)

Mandatory Fabric Module Requirement

To unlock the full per-slot bidirectional non-blocking switching throughput, the chassis must be equipped with a minimum of four matching Cloud-Scale FM-E / FM-E2 fabric modules. N+1 fabric module redundancy is not supported when mixing EX-series line cards with FX/FX3 line cards within the same chassis.

Standard Factory Complete Bundle Contents

Each factory-sealed N9K-X97040YC-EX retail/spare package contains all hardware required for chassis installation:

1. N9K-X97040YC-EX base hot-swappable Cloud-Scale line card with dual integrated passive aluminum heat sink assemblies
2. Front panel dust blanking plugs for all unused SFP+/SFP28 and QSFP28 ports
3. Chassis mounting retention screws and anti-static ESD handling storage bag
4. Quick-start hardware installation guide covering line card insertion, removal and replacement procedures
5. Global regulatory compliance, safety, and electromagnetic interference (EMI) certification documentation packet

Core Integrated Functional Capabilities

• Non-blocking wire-speed packet forwarding for all 40 SFP+/SFP28 downlink ports and 4 QSFP28 uplink ports simultaneously
• Hardware-accelerated Layer 2 / Layer 3 forwarding: IPv4/IPv6 unicast/multicast, MPLS label switching, Segment Routing, VXLAN EVPN tunnel termination for large-scale leaf/spine Clos fabrics and ACI leaf deployments
• Comprehensive Layer 2 feature suite: IEEE 802.1Q VLAN trunking (4096 VLAN IDs), vPC multi-chassis link aggregation, LACP/static EtherChannel, RSTP/MSTP spanning tree, UDLD, private VLANs, PVLAN edge isolation
• Layer 3 dynamic routing protocols: Static routing, RIPv2, OSPFv2/v3, EIGRP, BGP, HSRP/VRRP first-hop redundancy, uRPF loose/strict anti-spoofing mode
• Hardware security pipeline: Ingress/egress TCAM ACL filtering, DHCP snooping, dynamic ARP inspection, broadcast/multicast/unicast storm control, control-plane policing (CoPP)
• Hardware QoS scheduling: DSCP/802.1p CoS traffic classification, traffic policing/marking, ingress buffer tuning, egress DWRR weighted queuing, WRED congestion avoidance, native RoCEv2 priority scheduling for GPU cluster workloads
• Dedicated hardware multicast replication engine: PIM-SM, PIM-SSM, BiDir-PIM, MSDP, optimized for IPTV broadcast video and media fabric workloads
• Advanced data center automation & observability features: PoAP zero-touch provisioning, NX-API REST API, NETCONF/YANG, Python scripting, EEM embedded event manager, real-time streaming telemetry
• Full jumbo frame support up to 9216-byte MTU, SPAN/ERSPAN port mirroring, IEEE 1588 PTP boundary clock, NTP time synchronization, SSHv2 encrypted management, AAA/RADIUS/TACACS+ access control
• Dual operating mode support: Native NX-OS for traditional IP leaf/spine fabrics and ACI Leaf OS for policy-driven Application Centric Infrastructure multi-tenant data center deployments

2. Hardware & Performance Specifications

Core Forwarding & Buffer Performance

• Shared Packet Buffer: Large dynamic tunable shared buffer pool allocated evenly across all 44 ports
• Per-Slot Bidirectional Switching Throughput: Up to 1.6 Tbps full-duplex non-blocking crossbar
• Packet Forwarding Rate: Wire-speed L2/L3 forwarding for all standard Ethernet frame sizes
• Typical Forwarding Latency: 800 nanoseconds for Layer 2 switching, 1.2 microseconds for Layer 3 routing
• MAC Address Table Capacity: Up to 160,000 unique MAC address entries
• Maximum LPM IPv4/IPv6 Routes: 128,000 routing prefixes
• Multicast Route Scale: Up to 32,000 multicast route entries
• NetFlow Capacity: Hardware-accelerated NetFlow v5/v9 flow collection, supports massive volumes of concurrent flow cache entries
• MTBF (Mean Time Between Failures): 439,920 hours, delivering carrier-grade operational reliability

Port Hardware Specifications

Multi-Rate Downlink Ports (40 × SFP+ / SFP28 Ports)

• Supported Native Speeds: 1 Gbps SFP, 10 Gbps SFP+, 25 Gbps SFP28 Ethernet
• Supported Transceiver & Cable Types:
  • SFP 1G optical transceivers
  • SFP+ 10G SR/LR/ER optical transceivers, 10G twinax copper direct-attach cables
  • SFP28 25G SR/LR optical transceivers, 25G short twinax copper cables
• Maximum Cable Reach: Determined by the installed optical transceiver module

Universal QSFP28 Uplink Ports (4 × QSFP28 Multi-Rate Ports)

• Supported Native Speeds: 40 Gbps QSFP+, 100 Gbps QSFP28 Ethernet
• Breakout Mode Support: Each QSFP28 port can be split via dedicated breakout cables into multiple low-speed lanes:
  • 1 × 100G, 1 × 40G, 4 × 25G, 4 × 10G Ethernet per uplink port
• Supported Transceiver & Cable Types:
  • QSFP+ 40G SR4/LR4 optical transceivers
  • QSFP28 100G SR4/LR4/ER4 optical transceivers
  • QSFP+/QSFP28 passive/active copper direct-attach cables
  • QSFP28 breakout cables for 4×10G / 4×25G lane splitting

Electrical & Thermal Specifications

Power Consumption

• Typical Operating Power Draw Under Medium Traffic Load: ~320 Watts
• Maximum Full-Load Power Consumption: ~390 Watts
• Power Delivery: Powered exclusively through the chassis backplane; no external power supply connectors on the line card

Thermal & Environmental Operating Parameters

• Certified Continuous Operating Temperature Range: 0°C to 40°C (32°F to 104°F) standard data center environment
• Extended Validated Short-Term Operating Temperature: 0°C to 55°C (32°F to 131°F)
• Storage & Transport Temperature Range: -40°C to 70°C (-40°F to 158°F)
• Operating Relative Humidity: 10% to 90% RH, non-condensing
• Operating Altitude: Certified operational range -150 m to 2,000 m (-500 ft to 6,500 ft); extended validated range up to 3,000 m (10,000 ft)
• Cooling Design: Dual passive aluminum heat sink assemblies mounted on the line card PCB; cooling airflow is supplied by the host Nexus 9500 chassis rear fan trays
• Airflow Direction: Port-side intake, rear exhaust standard airflow design

Physical Form Factor & Weight

• Form Factor: Standard Nexus 9500 hot-swappable vertical Cloud-Scale line card form factor
• Bare Line Card Net Weight (without transceivers and dust blanking plugs): Approximately 5.0 kg

3. Regulatory & Compliance Certifications

Fully compliant with global international industry, safety, EMC, and carrier-grade standards when installed inside certified Nexus 9500 modular chassisCisco:

1. Safety Standards: UL 62368-1, CSA C22.2 No. 62368-1, EN 60950-1, IEC 60950-1
2. EMC & EMI Standards: FCC CFR Title 47 Part 15 Class A, VCCI Class A, EN55022 Class A, CISPR 22 Class A, GB 4943 Chinese national safety standard
3. Carrier-Grade Compliance: NEBS Level 3 (GR-1089-CORE, GR-63-CORE), ETSI ETS 300 386-2, EN 50121-4 railway EMC compatibility
4. Environmental Directive: EU RoHS 2 hazardous substance restriction compliance

4. Core Deployment Advantages

1. Optimized 40-Port Fiber Leaf Port Layout: 40 multi-rate 1G/10G/25G fiber access ports provide flexible connectivity for rack-mounted GPU compute servers, NAS storage arrays and top-of-rack aggregation, paired with four high-speed 40G/100G QSFP28 uplinks for leaf-to-spine fabric interconnection. The medium-density port design balances hardware cost and rack access port requirements for mid-scale data center leaf deployments.
2. Flexible Multi-Rate Breakout Uplink Design: Every QSFP28 uplink port supports multiple native speeds and configurable breakout lane layouts, enabling seamless coexistence of 10G/25G/40G/100G fabric uplink workloads without line card replacement. This capability supports gradual, phased bandwidth migration from 10G leaf-spine links to 100G high-throughput interconnections.
3. Large Dynamic Shared Packet Buffer Architecture: The line card’s oversized tunable shared packet buffer drastically reduces packet loss during extreme traffic bursts, such as GPU cluster parallel computing workloads, storage bulk data replication and media broadcast multicast streams. It delivers superior burst absorption performance compared to classic-generation line cards equipped with small fixed buffer pools.
4. Dual NX-OS / ACI Leaf Operating Mode Compatibility: Natively supports both standard NX-OS for traditional IP-based leaf/spine data center fabrics and ACI Leaf OS for Cisco Application Centric Infrastructure policy-driven multi-tenant data center deployments. A single hardware line card can be reused across both legacy IP fabrics and modern policy-based ACI environments, maximizing hardware asset flexibility.
5. Full Chassis Redundancy & Hot-Swap Compatibility: Fully interoperable with all Nexus 9500 high-availability chassis components, including redundant Cloud-Scale FM-E fabric modules, redundant AC power supplies and redundant rear fan trays. The hot-swappable design enables zero-downtime in-service line card insertion, removal and replacement without requiring the host chassis to be powered down, eliminating costly data center fabric downtime for hardware maintenance.
6. Cost-Optimized EX-Series LSE ASIC Architecture: The EX-generation LSE silicon omits dedicated hardware MACsec encryption acceleration to deliver a lower hardware bill-of-materials cost compared to FX-series line cards, making it the ideal cost-effective choice for mid-scale leaf-layer deployments where port-level MACsec encryption is not a mandatory requirement.
7. Comprehensive Hardware Acceleration of All Advanced Data Center Services: All core data center forwarding and security workloads — Layer2/Layer3 forwarding, ACL security filtering, QoS traffic scheduling, multicast replication, Segment Routing, VXLAN EVPN tunnel encapsulation/decapsulation and real-time streaming telemetry collection — are fully offloaded and accelerated on dedicated EX-series silicon ASICs. This eliminates supervisor CPU bottlenecks and maintains consistent wire-speed forwarding performance even under full port 100% traffic load conditions.

Supplementary Product Specification Notes

UNSPSC Classification Code

43222612 (Hot-swappable Cloud-Scale EX LSE ASIC hybrid I/O leaf line card for Cisco Nexus 9500 modular data center switch chassis, N9K-X97040YC-EX, 40-port multi-rate SFP+/SFP28 1/10/25G fiber downlink ports, 4-port QSFP28 multi-rate 40/100G fiber uplink ports with flexible breakout lane support, large dynamic shared packet buffer, hardware-accelerated L2/L3 forwarding, VXLAN EVPN and Segment Routing fabric support, dual NX-OS / ACI leaf operating modes, optimized for mid-scale enterprise, cloud and carrier data center leaf aggregation deployments for GPU compute, storage and server rack access).

K9 Security Compliance Note

All N9K-X97040YC-EX supported NX-OS and ACI Leaf OS firmware releases implement AES 128-bit encrypted remote CLI, web management portal, SNMP, and NETCONF management traffic, meeting Cisco K9 secure network hardware classification standards required for government, military, healthcare, and financial industry regulated data center deployments.

Factory Hardware Warranty Terms

Standard 1-year limited hardware warranty coverage for brand-new factory-sealed N9K-X97040YC-EX line card spare kits purchased through official Cisco authorized global distribution channel partners. Extended 3-year / 5-year hardware support contracts were available as optional add-ons via Cisco DNA Support Services during the product’s active sales lifecycle, covering spare part replacement, 24×7 Cisco TAC engineering technical support, and certified NX-OS / ACI Leaf OS firmware upgrade releases.