"Modular Core" vs "High-Density Access": N9K-C9364D-GX2A vs N9K-C9372PX, a Scenario-Driven Showdown

Aug 08 , 2025 5

1. "Modular Core" vs "High-Density Access": N9K-C9364D-GX2A vs N9K-C9372PX, a Scenario-Driven Showdown

In Cisco’s Nexus 9000 family, the N9K-C9364D-GX2A (hereinafter "9364D") and N9K-C9372PX (hereinafter "9372PX") are like "task-specific partners"—the former a "versatile all-rounder" for modular core switches, the latter a "high-density specialist" for access layers. This article breaks down their real-world differences across 15 dimensions to help you match them to your needs.

2. Performance Metrics: "Big Heart" of the Core vs "Multitool" of the Access Layer

Despite belonging to the same 9000 series, their roles drive significant hardware differences:

• Processing Speed:

• 9364D: Modular design with Cloud Scale ASIC (CSA), 400Gbps per-slot bandwidth (64×10G ports + 4×400G expansion slots), 32Tbps total capacity (fully populated); VXLAN latency 0.5μs, line-rate forwarding for data center cores.

• 9372PX: Fixed configuration with simplified ASIC, 100Gbps per-slot bandwidth (48×25G ports + 4×100G uplinks), 1.6Tbps total capacity; VXLAN latency 0.8μs (slightly higher but sufficient for enterprise access).

• Running Memory:

• 9364D: 32GB DDR4 (expandable to 256GB), supporting 2.5 million ACL rules;

• 9372PX: 16GB DDR3 (non-expandable), 800,000 flow entries, suited for small traffic (office terminals, IP cameras).

• Storage Capacity:

• 9364D: 16GB eMMC (expandable to 64GB), USB3.0 external drives (max 2TB) for logs/system images;

• 9372PX: No onboard storage, relies on USB2.0 (max 500GB) for OS, slower boot (20% delay).

3. Feature Sets: "Omnipotent Platform" of the Core vs "Vertical Tool" of the Access Layer

• 9364D:

• Modular expansion (mix-and-match line cards, service cards, expansion cards), supporting 400G/800G optics and hardware security/QoS cards;

• Deep integration with ACI, EVPN-VXLAN, SRv6, and micro-segmentation, ideal for hybrid cloud/multi-branch.

• 9372PX:

• Fixed 48×25G SFP28 + 4×100G QSFP28 uplinks, optimized for "high-density access";

• Native PoE++ (30W/port, 720W max), powering APs, phones, and cameras via one cable;

• Basic L2 features (VLAN, STP), no hardware encryption/QoS, suited for simple "endpoint-access" networks.

4. Design & Appearance: "Rack Professional" vs "Desk-Friendly"

• 9364D:

• Dimensions: 2RU × 88mm width × 680mm depth (25kg), front panel with 64×10G SFP+ + 4×400G QSFP-DD uplinks;

• Redundancy: Dual power supplies (1+1) + dual fans (N+1), hot-swappable, requiring 600mm-deep racks;

• Cooling: Bottom-to-top airflow, dependent on data center precision cooling.

• 9372PX:

• Dimensions: 1RU × 44mm width × 430mm depth (8kg), front panel with 48×25G SFP28 + 4×100G QSFP28 uplinks (3× port density of 9364D);

• Redundancy: Optional single power supply, no redundant fans (natural cooling), fitting small offices;

• Cooling: Front-to-rear through-flow, silent operation, office-friendly.

5. User Experience: Real Pains of Ops Teams

• 9364D:

• Strengths: Virtualized clustering (vPC+) simplifies cross-chassis management;

• Pain points: Complex configuration (managing 4 expansion slots), 3+ months learning curve; large logs (70GB/day) risk eMMC overflow.

• 9372PX:

• Strengths: Simplified CLI (70% fewer core-layer commands), "show interface" focused on key metrics (traffic/errors), IT staff proficient in 1 week;

• Pain points: Fixed ports, full replacement needed for new services; no virtualization, VRRP-dependent for redundancy.

6. Cost-Effectiveness: Long-Term Investment Math

• Initial Cost: 9364D ~¥1.3M (64×10G+4×400G slots), 9372PX ~¥350k (48×25G+4×100G), nearly 3× price difference.

• Expansion Costs:

• 9364D supports 400G/800G optics (~¥30k/module), flexible via slots;

• 9372PX fixed (no expansion), requires full replacement for bandwidth upgrades.

• Maintenance Costs:

• 9364D requires ACI licenses (~¥80k/year), automated ops (Ansible) reduce labor;

• 9372PX has no license fees but longer troubleshooting time (1.5+ extra hours daily), ideal for SMBs.

7. Product Advantages: Scenario-Driven "Uniqueness"

• 9364D: Ultra-high performance (32Tbps), flexible expansion, high reliability; perfect for data center cores, multi-branch interconnection, and hybrid cloud.

• 9372PX: High-density 25G ports (48), PoE++ (720W), simplified ops; ideal for campus access, branch aggregation, and AP/camera deployments.

8. System Upgrade: Details Determine Success (Key Section)

Upgrade Scenario: Migrating from NX-OS 9.3(7) to 10.4(3)F (IPv6 SRv6/hardware encryption).

Upgrade Process & Challenges:

1. Pre-Check Phase:

• 9364D: Use show module firmware to sync all modules, force upgrade with software upgrade module <slot> force;

• 9372PX: Verify optics with show interface transceiver vendor, replace non-Cisco modules.

• 9364D Issue: Module firmware mismatches (e.g., a service card at 9.3(5)) cause failures;

• 9372PX Issue: Third-party optics (non-Cisco 100G QSFP28) fail due to driver incompatibility.

• Fixes:

2. Backup & Rollback:

• 9364D: Split backups (configs to TFTP, logs to external server);

• 9372PX: Use copy running-config scp://admin@192.168.1.100/ for encrypted SSH transfers.

• 9364D Issue: 16GB eMMC may overflow when backing up configs/logs;

• 9372PX Issue: Slow USB2.0 backups (40MB/s) risk interruption.

• Fixes:

3. Downtime Control:

• 9364D: Disable non-essential services pre-upgrade (conf t ; no ip dhcp pool test-vlan);

• 9372PX: Use NSF/SSO for sub-30-second downtime via active-standby alternation.

• 9364D Issue: Rolling upgrades may disrupt traffic if non-critical services (e.g., test VLAN DHCP) run;

• 9372PX Issue: Full reboots cause 5-10 minute outages for core apps.

• Fixes:

4. Post-Upgrade Validation:

• 9364D: Add temporary IPv6 routes (ipv6 route 0.0.0.0/0 2001:db8::1) during migration;

• 9372PX: Load encryption licenses with license boot module c9300-ipservices, verify with show crypto ipservices.

• 9364D Issue: Strict IPv6 checks drop unrouted IPv6 traffic, breaking legacy devices;

• 9372PX Issue: Hardware encryption (IPSec) inactive without license.

• Fixes:

9. Product Use Cases

• 9364D Scenarios:

• Data center core: 100k+ VMs, ACI for cross-AZ isolation, hybrid modules (400G line cards + firewalls);

• Multi-branch interconnection: EVPN-VXLAN with hardware IPSec, 25μs latency for real-time trading.

• 9372PX Scenarios:

• Campus access layer: 500+ APs/phones, PoE++ (720W) eliminates extra power cabling;

• Branch aggregation: MPLS VPN with 50ms BFD failover, ensuring ERP stability.

10. Detailed Pros & Cons

11. Conclusion: How to Choose?

• 9364D: For hyperscale data center cores, multi-branch interconnection, or future expansion plans.

• 9372PX: For small-to-medium networks (<5,000 endpoints), cost-sensitive deployments, or PoE-heavy access needs.