MSN3420-CB2RO - 48x25GbE 12x100GbE Spectrum-2 Switch | NVIDIA
MPN: MSN3420-CB2RO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
MSN3420-CB2RO Overview
An Open Ethernet switch is a network switch sold without a pre-loaded network operating system. The ONIE (Open Network Install Environment) bootloader lets the operator install any compatible NOS, such as Cumulus Linux, SONiC, or Onyx. In the data center hierarchy, these platforms serve as leaf or top-of-rack (ToR) switches within leaf-spine architectures built on merchant silicon switching ASICs.
Key features include the Spectrum-2 ASIC providing line-rate Layer 2/Layer 3 forwarding with consistent low latency, 48-port 25G SFP28 density with 12x 100G QSFP28 uplinks, redundant hot-swappable 2x AC power supplies, front-to-back C2P airflow for hot-aisle exhaust, and a 1U rack-mount chassis. The platform supports port speeds from 1GbE to 100GbE depending on optics.
The Spectrum-2 family is purpose-built for cloud-scale leaf/spine/super-spine data center networks, supporting advanced software-defined networking features. NVIDIA documentation describes the SN3000 series as delivering high performance, consistent low latency, and web-scale reliability for cloud, hyperconverged storage, and data analytics applications.
Typical deployments include top-of-rack server connectivity in hyperscale and enterprise data centers, leaf-layer aggregation in leaf-spine fabrics, storage network fabrics, and Open Networking white-box projects where NOS choice flexibility is required.
Design consideration: because the RO suffix indicates ONIE-only with no pre-installed NOS, plan NOS licensing and installation before deployment; also verify airflow direction (C2P) matches rack cooling layout.
This page synthesizes distributor availability, sibling-SKU alternatives, and deployment guidance not found together on manufacturer or distributor pages.
Drop-in alternatives for MSN3420-CB2RO — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MSN3420-CB2RO (same form factor and footprint) — differing in Airflow, Form Factor, Power Supplies, Product Type, Switching Capacity.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MSN3420-CB2R
✅ Drop-In📋 Reference alternative (not in catalog)
MSN3420-CB2FC
✅ Drop-In✓ In Stock
$16200 / Unit
View Datasheet →MSN3420-CB2FO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
Contact for price
View Datasheet →SSE-SN3420-CB2RC
✅ Drop-In📋 Reference alternative (not in catalog)
MSN3420-CB2RO Specifications (manufacturer-published)
| Product Type | 1U Open Ethernet switch (Spectrum-2, SN3420) |
| SFP28 Ports (25GbE) | 48 |
| QSFP28 Ports (100GbE) | 12 |
| Switching Capacity | 4.8 Tbps |
| ASIC | NVIDIA Spectrum-2 |
| Layer Support | Layer 2 / Layer 3 managed |
| Network Install Environment | ONIE bootloader, no NOS pre-installed |
| Form Factor | 1U rack-mount |
| Power Supplies | 2x AC PSU (redundant, hot-swappable) |
| Airflow | C2P (connector-to-panel, front-to-back) |
| Application Target | Top-of-rack / leaf-spine data center |
| Series | SN3000 (Spectrum-2) |
| Supported Port Speeds | 1GbE to 100GbE (per NVIDIA SN3000 series datasheet) |
| Mounting | 19-inch rack |
MSN3420-CB2RO Interfaces & Connectors
No manufacturer-published interface list is available for MSN3420-CB2RO. Refer to the manufacturer documentation for connector and header details.
Refer to the manufacturer documentation for the full expansion header pinout and connector pin numbering.
Typical Applications
MSN3420-CB2RO is suitable for 6 applications: Top-of-Rack (ToR) Server Connectivity, Leaf Layer in Leaf-Spine Fabrics, Cloud and Web-Scale Data Center Networks, Hyperconverged and Storage Fabrics, Open Networking / White-Box NOS Lab and Staging, Enterprise Data Center Refresh (10G to 25G Migration).
Top-of-Rack (ToR) Server Connectivity
The MSN3420-CB2RO is a purpose-built top-of-rack switch: its 48x SFP28 ports provide 25GbE connectivity to servers in a single 1U rack unit, while the 12x QSFP28 100GbE ports deliver high-bandwidth uplinks toward the spine layer. The Spectrum-2 ASIC forwards at line rate with consistent low latency, which matters for east-west traffic in virtualized and containerized environments. Because it ships ONIE-only, operators can install SONiC, Cumulus Linux, or another NOS of choice, standardizing software across mixed-vendor racks. The 2x redundant AC PSUs and C2P airflow match typical data center hot-aisle exhaust layouts. A single 1U platform replacing multiple 10G switches reduces cabling, power, and rack-space overhead substantially in dense compute rows.
Recommended
Leaf Layer in Leaf-Spine Fabrics
In a leaf-spine architecture, the MSN3420-CB2RO acts as a leaf switch aggregating 48 rack servers at 25GbE and connecting northbound to up to 12 spine systems over 100GbE QSFP28 links. The Spectrum-2 ASIC provides non-blocking 4.8 Tbps fabric capacity and Layer 3 features such as ECMP, enabling predictable low-latency any-to-any connectivity required by microservices and storage traffic. NVIDIA's SN3000 series documentation positions this family specifically for leaf/spine/super-spine cloud-scale networks with advanced software-defined networking features. The ONIE-only RO variant lets network teams run the same SONiC or Cumulus image on every leaf, simplifying automation with configuration management tools and reducing operational divergence across the fabric.
Recommended
Cloud and Web-Scale Data Center Networks
Hyper-scale and cloud operators deploy the MSN3420-CB2RO where port density, telemetry, and software freedom matter more than bundled NOS licensing. The NVIDIA SN3000 series datasheet describes the family as ideal for cloud-scale Layer 2/Layer 3 networks supporting web-scale IT, hyperconverged storage, and data analytics. The Spectrum-2 ASIC supports advanced SDN features for automated fabric management. Open Ethernet with ONIE means the same hardware can carry different NOS generations over its service life, protecting the hardware investment. With 4.8 Tbps in 1U and 2x hot-swap AC PSUs, the platform delivers high throughput per watt and per rack unit, which directly reduces total cost of ownership at fleet scale.
Recommended
Hyperconverged and Storage Fabrics
Hyperconverged storage clusters generate heavy east-west traffic patterns that benefit from the MSN3420-CB2RO's non-blocking 25GbE server ports and 100GbE uplinks. The Spectrum-2 ASIC's consistent low latency reduces jitter for iSCSI, NVMe-oF over Ethernet, and distributed storage replication traffic, improving IOPS consistency under load. NVIDIA identifies hyperconverged storage as a target workload for the SN3000 series. Redundant hot-swappable PSUs and field-replaceable fans support the high availability demands of storage networks. Because the RO unit is ONIE-only, storage vendors' certified NOS images (including SONiC-based stacks) can be installed and validated per the storage OEM's interop list before rollout, ensuring the fabric layer matches the array vendor's support matrix.
Recommended
Open Networking / White-Box NOS Lab and Staging
The ONIE-only MSN3420-CB2RO is well suited to Open Networking engineering labs where teams validate NOS builds (SONiC, Cumulus Linux, Onyx) on production-class Spectrum-2 silicon before fleet deployment. Because ONIE is the industry-standard installer environment, the same unit can be repeatedly re-imaged with different NOS versions for regression and interop testing. The 48x SFP28 plus 12x QSFP28 port mix reproduces a realistic ToR topology in the lab, allowing full-scale routing, telemetry, and automation testing. Standard ONIE procedures also make the platform a common reference target in vendor certification programs, and BrightStar and other secondary sellers supply cost-effective units for lab fleets without consuming production-budget hardware.
Recommended
Enterprise Data Center Refresh (10G to 25G Migration)
Enterprises upgrading server access from 10GbE to 25GbE adopt the MSN3420-CB2RO because SFP28 ports are backward-compatible with 10G SFP+ optics and DACs, enabling a phased migration without replacing every transceiver on day one. The 12x 100GbE QSFP28 uplinks consolidate what previously required multiple 40G uplink bundles, simplifying the spine design. The Spectrum-2 ASIC delivers line-rate Layer 2/Layer 3 with consistent low latency for enterprise applications, and NVIDIA's SN3000 documentation highlights flexible port speeds from 1GbE upward. With 2x AC PSUs and 1U density, existing racks and power circuits are reused. The RO ONIE variant lets enterprise teams standardize on one NOS across data centers during the refresh cycle.
Recommended
Recommended Products Summary
Engineering reference data for MSN3420-CB2RO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MSN3420-CB2R | MSN3420-CB2FC | MSN3420-CB2FO | SSE-SN3420-CB2RC |
|---|---|---|---|---|---|
| Brand | NVIDIA (Mellanox) | NVIDIA (Mellanox) | NVIDIA (Mellanox) | NVIDIA (Mellanox) | Supermicro |
| Package / Form Factor | 1U rack-mount | 1U rack-mount - same | 1U rack-mount - same | 1U rack-mount - same | 1U rack-mount - same |
| ASIC | NVIDIA Spectrum-2 | Spectrum-2 | Spectrum-2 | Spectrum-2 | Spectrum-2 |
| Lifecycle Status | Active (channel/secondary market) | Active | Active | Active | EOL (per Supermicro) |
Key Differentiators
- NOS freedom with ONIE-only loading (vs MSN3420-CB2R)
- C2P airflow matching hot-aisle exhaust racks (vs MSN3420-CB2FC)
- Active availability vs EOL cross-brand alternative (vs SSE-SN3420-CB2RC)
Design Notes
Deploy with both AC PSUs connected to independent power feeds (A/B feeds) to use the redundant hot-swap design. NVIDIA's SN3000 ordering documentation stresses matching airflow when ordering PSUs - replacement PSUs must match the C2P system airflow. Verify rack PDU capacity against the switch's rated power draw before installation; consult the SN3000 Hardware User Manual on docs.nvidia.com for per-SKU power figures.
The RO suffix means ONIE bootloader only - no network operating system. Plan NOS procurement, licensing, and installation windows before the unit arrives; a switch without a NOS cannot pass production traffic. Do not confuse airflow variants: C2P (CB2RO/CB2R) exhausts front-to-back, while CB2FC/CB2FO use C2F. Mixing airflow directions in one rack causes thermal shutdowns. Also note the alldatasheet.com 'MSN3420' PDF is an unrelated MOSFET - use only NVIDIA's SN3000 documentation.
In the physical install, use QSFP28 DACs for intra-rack spine/leaf links under 3 m to save cost and power, and optics for longer runs. Ensure front and rear rack clearances per the Hardware User Manual so the C2P airflow path is unobstructed. Label ports per your leaf-spine cabling plan before cable installation; the 48+12 port density is error-prone without documentation.
Compliance Information
Compliance statements for this switch system were not present in the provided web data; consult NVIDIA SN3000 series regulatory documentation.
