DCS-7124FX-R Arista 7124FX 10GbE SFP+ Rear-to-Front 24 Ports Managed Switch

Arista DCS-7124FX-R 7124FX 24 Ports Managed Switch

The Arista DCS-7124FX-R is a high-density, low-latency 10 Gigabit Ethernet switch engineered for performance-critical environments. As part of Arista's renowned 7100 Series, this 1U rack-mountable switch delivers 24 wire-speed SFP+ ports in a unique rear-to-front airflow configuration, making it an ideal solution for top-of-rack (ToR), leaf layer, and high-performance computing (HPC) deployments. Built on Arista's Extensible Operating System (EOS), it provides robust Layer 3 functionality, advanced visibility, and automated network control.

Core Specifications

At its heart, the DCS-7124FX-R is designed for uncompromising performance and reliability. It serves as a critical aggregation point for servers, storage, and other network infrastructure requiring high-bandwidth, low-latency connectivity.

Speed and Density

The switch provides 24 fixed 10 Gigabit Ethernet SFP+ ports, each capable of operating at 1G or 10G speeds depending on the installed optic or DAC cable. This port density in a 1U form factor allows for efficient consolidation of server and storage connections, maximizing rack space and minimizing cabling complexity.

Switch Fabric and Throughput

The DCS-7124FX-R features a non-blocking switch fabric architecture. With an aggregate switching capacity of 480 Gbps (full-duplex) and a forwarding rate of 357 million packets per second (Mpps), it ensures all ports can operate at line rate simultaneously without congestion or packet loss, even under fully saturated conditions.

Latency Characteristics

Engineered for financial trading, HPC, and real-time analytics applications, the switch exhibits ultra-low latency. Typical latency is sub-microsecond for cut-through switching mode, making it suitable for the most latency-sensitive workloads.

Form Factor and Physical Design

The 1U rack-mountable design is optimized for standard data center racks. Its robust metal construction ensures durability, while the thoughtful layout facilitates serviceability and cable management.

Rear-to-Front Airflow (R2F)

A defining characteristic of the DCS-7124FX-R model is its rear-to-front cooling airflow. This is crucial for deployments in data centers with hot aisle/cold aisle containment strategies where cooling is directed from the front of the rack to the rear. The power supplies and fan trays intake air from the port side (rear) and exhaust to the front, aligning with modern data center thermal management best practices.

Power Supply and Redundancy

The switch typically ships with dual, hot-swappable AC power supplies configured in a 1+1 redundant configuration. This ensures continuous operation in the event of a single power supply failure, enhancing overall system availability. The unit supports a wide range of input voltages for global deployment flexibility.

Fan Module Design

It includes redundant, hot-swappable fan modules. Fans are speed-controlled based on thermal sensors, balancing cooling efficiency with acoustic noise. The modular design allows for quick replacement without disrupting operation.

Layer 3 Routing and Protocol Support

As a fully managed Layer 3 switch, the DCS-7124FX-R performs not only high-speed switching but also advanced IP routing, making it suitable for dynamic data center fabrics.

Unicast Routing Protocols

The switch supports a comprehensive suite of dynamic routing protocols for building scalable, resilient networks. This includes OSPFv2/v3 and BGPv4/v6 for enterprise and data center interconnect routing. Protocol implementations are full-featured and scalable, supporting large routing tables and complex network topologies.

Multicast Routing for Efficient Data Distribution

For applications like financial market data, video streaming, or cluster communications, the switch offers robust IP multicast support. It implements Protocol Independent Multicast Sparse Mode (PIM-SM), Source-Specific Multicast (SSM), and IGMP snooping, ensuring efficient bandwidth utilization for multi-destination traffic flows.

Advanced Features for Network Visibility and Control

The DCS-7124FX-R includes a suite of features designed to provide granular visibility into network traffic and enable precise control over quality of service (QoS).

Precision Timing with PTP and NTP

For applications requiring synchronized clocks, such as financial trading or scientific computing, the switch supports Precision Time Protocol (PTP, IEEE 1588). It can operate as a boundary or transparent clock, distributing accurate timing across the network. Network Time Protocol (NTP) is also supported for general time synchronization.

High Availability and Resiliency Features

Network uptime is paramount, and the DCS-7124FX-R incorporates multiple hardware and software features to ensure continuous operation.

Hardware Redundancy

Beyond the dual power supplies and fan modules, the switch architecture includes redundant boot flash devices. The control plane is protected by hardware watchdogs and self-monitoring processes within EOS.

Virtual Router Redundancy Protocol (VRRP)

For default gateway redundancy at the ToR layer, the switch supports VRRP. This allows two or more switches to share a virtual IP and MAC address, providing seamless failover for connected hosts if the primary gateway switch becomes unavailable.

Security and Access Control

Protecting network infrastructure and data is critical. The DCS-7124FX-R provides a layered security model.

Management Plane Security

Access to the switch is controlled via multiple methods: SSHv2, out-of-band management Ethernet, and role-based access control (RBAC). All management traffic can be segregated onto a dedicated VRF (Virtual Routing and Forwarding) instance. Integration with TACACS+ and RADIUS servers enables centralized authentication, authorization, and accounting (AAA) for administrative users.

Control Plane Protection (CoPP)

To prevent denial-of-service attacks targeting the switch's CPU, Control Plane Policing (CoPP) is implemented. This feature uses QoS policies to rate-limit and prioritize traffic destined to the switch's control plane, ensuring management and routing protocol stability even under adverse conditions.

Data Plane Security

The switch supports MACsec (IEEE 802.1AE) encryption on selected ports, providing hardware-accelerated, link-layer security for data confidentiality and integrity between switches or between a switch and a server. Dynamic ARP inspection (DAI), IP Source Guard, and DHCP snooping help mitigate spoofing attacks within a layer 2 domain.

Deployment Use Cases and Applications

The versatility of the DCS-7124FX-R makes it a fit for several key data center and high-performance networking roles.

High-Performance Top-of-Rack (ToR) Switching

Its 24x 10GbE port density and 1U form factor make it a premier choice for ToR deployment in server racks. It provides abundant bandwidth for modern multi-core servers with high-speed NICs, supporting virtualization, big data, and web-scale applications. The rear-to-front airflow is specifically advantageous in such environments.

Leaf Switch in Spine-Leaf Architectures

In modern leaf-spine (Clos) fabric designs, the DCS-7124FX-R excels as a leaf switch. Its full Layer 3 capabilities, support for equal-cost multi-path routing (ECMP), and low latency are essential for building scalable, non-blocking data center networks. It connects compute and storage resources to the high-bandwidth spine layer.

Financial Trading and Low-Latency Environments

The combination of cut-through switching, sub-microsecond latency, PTP timing, and LANZ congestion monitoring caters directly to algorithmic trading, market data distribution, and other latency-intolerant applications. Its deterministic performance is critical in these scenarios.

Storage Networking and IP-Based SAN

With support for jumbo frames (up to 9214 bytes MTU or more), advanced buffer management, and lossless Ethernet features, the switch is well-suited for converging network and storage traffic on a unified IP fabric, supporting protocols like iSCSI and FCoE (with appropriate licensing).