Mellanox ConnectX-4 Lx MCX4121A-ACAT Dual-Port 25GbE Network Adapter Card

Mellanox ConnectX-4 Lx EN MCX4121A-ACAT Ethernet Adapter Card - A high-performance dual-port 25GbE network card designed for demanding virtualized, cloud, and storage workloads, delivering hardware-accelerated networking with sub-microsecond latency.

• Dual-Port, Multi-Speed Connectivity: Two SFP28 ports supporting 1GbE, 10GbE, and 25GbE speeds for flexible deployment and link aggregation.
• Ultra-Low Latency & High Throughput: Sub-microsecond latency and a message rate of up to 75 million packets per second.
• Hardware RDMA Acceleration: Native support for RoCE v1 & v2, enabling efficient remote direct memory access over Ethernet networks.
• Advanced Virtualization: SR-IOV technology supporting up to 256 Virtual Functions (VFs) per port for near-native VM performance.
• Overlay Network Offload: Full hardware offload for encapsulation/decapsulation of VXLAN, NVGRE, and GENEVE tunnels.
• CPU Offload Engines: Comprehensive offloads for TCP/UDP/IP checksum, large send, VLAN operations, and Receive Side Scaling (RSS).
• Robust Management: Features like UEFI enablement, secure firmware updates, and host management interfaces (NC-SI over MCTP).

• Interconnect Standard: PCI Express 3.0 (8 GT/s) with backward compatibility to Gen 2.0 and 1.1.
• Ethernet Standards: Fully compliant with IEEE 802.3by (25GbE), 802.3ae (10GbE), and supports Energy Efficient Ethernet (EEE).
• Virtualization: Single Root I/O Virtualization (SR-IOV) for hardware-based I/O isolation and performance.
• RDMA Protocol: RDMA over Converged Ethernet (RoCE), leveraging Data Center Bridging (DCB) for lossless operation.
• Overlay Protocols: Hardware acceleration for VXLAN, NVGRE, and GENEVE encapsulation standards.
• Management: Supports NC-SI over MCTP for out-of-band management via a Baseboard Management Controller (BMC).

The MCX4121A-ACAT operates as an intelligent intermediary between the server's PCIe bus and the network. Upon receiving data from applications, its onboard ASIC performs numerous hardware offloads:

Data Path Example: Application Data → Socket Buffer → (Offload: TCP Segmentation, Checksum) → (If Overlay: VXLAN Encapsulation Offload) → RDMA Engine / Ethernet MAC → SFP28 Transceiver → Network.

For virtualized environments, the SR-IOV firmware creates direct hardware pathways (Virtual Functions) for individual VMs, bypassing the hypervisor's virtual switch for critical I/O and drastically reducing latency. The RoCE engine allows applications on separate servers to read/write directly to each other's memory, minimizing CPU involvement and speeding up cluster communication.

• Hyperconverged Infrastructure (HCI) & Virtualization: Ideal for VMware vSphere, Microsoft Hyper-V, and KVM hosts requiring high VM density and network performance.
• Cloud & Web 2.0 Platforms: Provides the high message rate and consistent low latency needed for front-end web servers, caching layers, and database clusters.
• Storage Networking: Accelerates IP-based storage protocols like iSER (iSCSI Extensions for RDMA) and NFS over RDMA, consolidating compute and storage traffic.
• High-Performance Computing (HPC) & AI/ML: Enables low-latency communication between compute nodes in clusters using MPI libraries over RoCE.
• Overlay Network Gateways: Efficiently handles encapsulated traffic in software-defined networking (SDN) and NSX environments.

• Superior Total Cost of Ownership (TCO): By offloading network processing from CPUs, it allows servers to support more VMs or applications, improving hardware utilization and delaying costly server refreshes.
• Unmatched Feature Density: Combines high-speed connectivity, advanced offloads, and robust virtualization in a single NIC card, eliminating the need for multiple specialized adapters.
• Proven Ecosystem Integration: As a foundational component in many OEM servers and validated with major hypervisors and orchestration platforms, it ensures reliable interoperability.
• Future-Proof Design: Support for modern overlay protocols and RoCE positions this network card as relevant for next-generation, software-defined data centers.
• Performance Consistency: Hardware-based offloads guarantee predictable, low-latency performance even under heavy network loads, which is critical for financial trading or real-time analytics.

• Warranty: Standard manufacturer warranty. Extended warranty and support plans are available upon request.
• Inventory & Availability: This NIC card is maintained in stock within our large global inventory, ready for prompt shipment to meet project timelines.
• Technical Expertise: Our dedicated technical support team offers pre-sales consultation and post-sales troubleshooting for integration with various server and switch platforms.
• Software & Driver Support: We provide access to the latest stable drivers, firmware updates, and compatibility guides for major operating systems.
• Global Logistics: Reliable worldwide shipping with full tracking to ensure accurate and timely delivery.

• Server Compatibility: Verify that your server chassis has sufficient physical space for a low-profile card and that the PCIe slot provides adequate power (typically up to 25W).
• Thermal Management: Ensure adequate airflow within the server chassis, especially in dense configurations, to maintain optimal adapter operating temperatures.
• Driver & Firmware: Always install the recommended driver and firmware version from the official Mellanox support website for your specific operating system to ensure stability and access to all features.
• Electrostatic Discharge (ESD): Handle the card with proper ESD precautions. Always place it on an anti-static surface and use a wrist strap when installing.
• Software Configuration: For advanced features like SR-IOV or RoCE, specific BIOS/UEFI settings (e.g., enabling SR-IOV support, configuring PCIe bandwidth) and OS-level configurations are required. Consult the product installation guide.

With a track record spanning more than a decade, we have established ourselves as a leading global supplier of enterprise-grade networking hardware, supported by substantial manufacturing resources and a deep bench of technical experts.

We are a trusted distributor for top-tier brands including NVIDIA (Mellanox), Aruba, Ruckus, and Extreme. Our core offerings consist of authentic, brand-new networking equipment such as data center switches, network interface cards (NIC cards), wireless access and control systems, and comprehensive cabling solutions.