NVIDIA Mellanox MSN3420-CB2FC Spectrum-Based 1U Ethernet Switch, 48× SFP28 25GbE + 12× QSFP28 100GbE, Cumulus Linux, P2C Airflow: This is a 1U fixed-configuration top-of-rack Ethernet switch with 48 SFP28 ports (25GbE) and 12 QSFP28 ports (100GbE) on a Spectrum ASIC platform. The unit ships with Cumulus Linux pre-installed and uses port-to-connector (P2C) airflow. This is a Layer 2/3 Ethernet switch; it is NOT an InfiniBand switch and it is NOT a chassis/modular system. NVIDIA P/N: 920-9N213-00F7-0C0. Refurbished, in TES IT-SOLUTIONS stock.
Engineering Context: The MSN3420-CB2FC is built around the NVIDIA Spectrum Ethernet ASIC and exposes a mixed-speed access/uplink topology: 48 SFP28 ports support 1/10/25GbE per port, while the 12 QSFP28 ports support 40/100GbE and can be split via breakout cabling into 4×10GbE or 4×25GbE per QSFP28 (subject to license/profile). Cumulus Linux provides a Debian-based NOS with full programmable Layer 2/3 (BGP, OSPF, EVPN/VXLAN, MLAG), automation hooks (Ansible, Puppet, NetQ), and standard Linux toolchain access. The switch is rated for hot/cold aisle deployments via P2C (front-to-back, port side intake) airflow and ships with dual hot-swappable AC PSUs.
Deployment & Use Cases: Designed for top-of-rack deployment in modern data centers running 25GbE-to-server with 100GbE uplinks. Common workloads include AI/ML training cluster east-west fabrics, leaf switches in EVPN/VXLAN spine-leaf overlays, NVMe-oF over RoCE storage networks, and Kubernetes/OpenStack tenant networking where Cumulus automation is required.
Technical Specifications:
MPN: MSN3420-CB2FC
NVIDIA P/N: 920-9N213-00F7-0C0
ASIC: NVIDIA Spectrum
Form Factor: 1U fixed
SFP28 Ports: 48 (1/10/25GbE)
QSFP28 Ports: 12 (40/100GbE; breakout-capable)
NOS: Cumulus Linux (pre-installed)
Airflow: P2C (port-to-connector, front-to-back)
Power Supplies: Dual hot-swappable AC
Layer Support: Layer 2 and Layer 3 (BGP, OSPF, EVPN/VXLAN, MLAG)
Management: 1× RJ45 mgmt, 1× console (RJ45/USB), 1× USB
Condition: Refurbished
Compatibility & Constraints: Requires SFP28/QSFP28 transceivers or DAC/AOC cables compatible with NVIDIA Mellanox Spectrum (sold separately). The MSN3420-CB2FC is the Cumulus-licensed variant; it is NOT the Onyx (MLNX-OS) variant, and it is NOT an InfiniBand switch. P2C airflow is fixed for this SKU; for reverse (C2P) airflow a different SKU is required. Verify aisle airflow direction in your rack before deployment.
Why TES: T.E.S IT-SOLUTIONS ships from EU stock with 1–3 day handling. Each refurbished switch is inspected, powered, and tested. Contact our team for transceiver compatibility verification, fabric design, and bulk pricing.