NVIDIA Mellanox MSN2740-CB2R1C 1U Spectrum 100GbE Open Ethernet Switch: This is a 1U short-depth Open Ethernet aggregation/spine switch built on the NVIDIA Mellanox Spectrum ASIC, providing 32 × 100GbE QSFP28 ports. This SKU ships with Cumulus Linux pre-installed; the platform is also re-flashable with NVIDIA Mellanox Onyx, SONiC, or other ONIE-installable NOS via the ONIE bootloader. This is NOT a 200GbE or 400GbE switch — each QSFP28 port operates at 100GbE (or breakout speeds) and uses 4×25G NRZ lanes, not 50G PAM4. This is a refurbished unit.
Engineering Context
The Spectrum ASIC provides 6.4 Tbps non-blocking switching capacity and up to 4.76 Bpps packet forwarding. Typical port-to-port latency is approximately 300 ns. Each QSFP28 port supports 4×25G or 2×50G breakout, allowing up to 64 × 50GbE or 128 × 25GbE downlink configurations. The "R" suffix indicates C2P airflow — air enters at the connector (port) side and exits at the power-supply side.
Deployment & Use Cases
100GbE leaf-spine fabrics for cloud and enterprise data centers. AI/ML training cluster aggregation for ConnectX-5 and ConnectX-6 NICs. HPC compute fabric backbones. Storage-network spines for Ceph, Lustre, and BeeGFS at 100GbE. Open networking deployments running Cumulus Linux, NVIDIA Onyx, SONiC, or other ONIE-installable NOS.
Technical Specifications
OEM: NVIDIA Mellanox
Part Number: MSN2740-CB2R1C
ASIC: NVIDIA Mellanox Spectrum
Ports: 32 × 100GbE QSFP28
Switching Capacity: 6.4 Tbps
Packet Rate: up to 4.76 Bpps
Latency: ~300 ns port-to-port
Operating System: Cumulus Linux (pre-installed)
Control CPU: x86
Airflow: C2P (Connector-to-Power)
Power Supplies: 2 × AC, hot-swap (1+1 redundant)
Form Factor: 1U short-depth
Compliance: RoHS6
Condition: Refurbished — Tested by T.E.S IT-SOLUTIONS
Compatibility & Constraints
Compatible with NVIDIA Mellanox LinkX QSFP28 transceivers, DACs (e.g., MCP1600 family), and AOCs (e.g., MFA1A00 family). Supports 4×25G and 2×50G breakout to SFP28 endpoints via QSFP28-to-4xSFP28 cables. This is an Ethernet-only switch — the MSN2740 family does not run in VPI/InfiniBand mode (use the SB7700 or QM-series for InfiniBand). Rail kit is not included. The 100GbE QSFP28 ports use NRZ 25G lanes and do NOT auto-negotiate to 200GbE QSFP56 or 400GbE QSFP-DD optics.
Why Choose T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS tests every refurbished switch for port integrity at 100GbE line-rate, PSU redundancy, fan operation, and OS/bootloader integrity before shipment. Visit www.tes-itsolutions.com for the full Spectrum and ConnectX inventory. Standard handling time is 1–3 business days.