Juniper QFX5120-48Y 48-Port 25GbE Data Centre Switch

The Juniper QFX5120-48Y is a flagship leaf switch for data centre racks that need practical 25GbE server access with clean uplinks into the wider fabric. Its Layer 3 design and hot-swappable power supplies help modernise infrastructure with resilient, high-throughput connectivity.

QFX5120-48Y Key Platform Specifications

  • Primary Use Case: Leaf
  • Access Ports: 48
  • Port Configuration: 48×SFP28 + 8×QSFP28
  • Maximum Port Speed: 100G
  • Switching Capacity (Gbps): 4000
  • Routing Capability: Dynamic
Starting from: £3795.00 Ex. VAT

QFX5120-48Y Overview

Modern rack-scale environments need dense server connectivity, predictable east-west throughput and clean paths into the wider fabric as application demands keep rising.

Leaf Switching for High-Density Racks

Juniper QFX5120-48Y is a leaf switch for data centre deployments where many servers need 25GbE access without forcing an immediate jump to 100GbE at the host. Its 48×SFP28 + 8×QSFP28 port mix suits consolidated racks that still need headroom for uplinks and fabric expansion.

Designed for Dense Fabric Connectivity

With 4000 Gbps switching capacity, the platform is built to carry high volumes of rack traffic between compute, storage and adjacent network tiers. That makes it a practical fit when oversubscription, latency and port density all have to be balanced in the same leaf layer.

Operational Fit for Growth and Modernisation

The result is a cleaner way to modernise server connectivity, extend rack-scale capacity and keep the network layout aligned with evolving workloads. It gives infrastructure teams a straightforward path to higher-speed access while preserving fabric simplicity.

If you are planning a rack refresh or leaf/spine expansion, our team can help you evaluate the Juniper QFX5120-48Y for your production environment.

QFX5120-48Y Key Features​

The Juniper QFX5120-48Y is a data center switching platform for high-density leaf-spine and aggregation deployments, delivering a scalable network foundation for modern enterprise and cloud environments.

Scalable Data Center Fabric

High-Density Server Connectivity
The platform supports 48x SFP28 ports for dense access-layer connectivity in data center networks.

Uplink Fabric Expansion
The platform includes 8x QSFP28 uplink ports for high-bandwidth aggregation and spine connections.

100G-Focused Architecture
The switching design supports up to 100G speed for high-throughput fabric and uplink roles.

High-Capacity Switching Core
The switch provides 4000 Gbps of switching capacity to sustain demanding east-west traffic patterns.

Operational Network Control

Fabric-Oriented Deployment
The architecture is suited to structured leaf-spine designs that simplify scaling and network segmentation.

Capacity Headroom
The platform’s switching resources are designed to maintain performance as port utilization and traffic density increase.

Aggregation Flexibility
The port mix supports both server-facing access and upstream aggregation within a single switching platform.

Speak to a Juniper Networking Specialist

If you are planning a high-density data center fabric, our team can help align the QFX5120-48Y with your access, aggregation, and spine connectivity requirements.

QFX5120-48Y Technical Specifications

Full specifications for this model are listed below.

Additional information

Product Family

Juniper QFX

Product Series

QFX5120

Deployment

Data Centre

Target Organisation Size

Enterprise

Primary Use Case

Leaf

Product Tier

Flagship

Network Architecture

Layer 3

Access Ports

48

Access Port Architecture

SFP28

Total Ports

56

Maximum Port Speed

100G

Port Configuration

48×SFP28 + 8×QSFP28

PoE

No

Stacking

Supported

Operating System

Power Redundancy

Hot-swappable PSUs

Maximum VLANs

4096

Routing Capability

Dynamic

Switching Capacity (Gbps)

Evaluating whether this is the right fit for your environment?

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QFX5120-48Y Deployment Scenarios

The Juniper QFX5120-48Y is a 25GbE leaf switch for data centre racks and service environments that need dense server connectivity, predictable latency and clean 100GbE uplinks. It fits teams standardising east-west traffic without moving every host to 100GbE.

Leaf Switching for Modern Data Centre Racks

In colocation and enterprise data centres, rack designs often centre on many 10/25GbE servers with a smaller number of uplinks. This switch supports that balance, reducing oversubscription pressure while keeping spine connectivity simple.

CI, Kubernetes and Virtualisation Fabrics

Platform and engineering teams running build, test and virtualisation clusters need fast server-to-server movement without wasting ports on oversized host links. The QFX5120-48Y gives dense 25GbE access for lab-to-production fabrics.

Analytics and Back-Office Compute Racks

Finance environments with reporting, risk and back-office workloads usually need low-latency access across many servers, not a full 100GbE port per host. This model supports that scale with practical 25GbE density.

Storage and Render Networks in Media Production

Media teams handling large files, shared storage and render nodes need sustained throughput between many production systems. The QFX5120-48Y provides 25GbE server links and 100GbE uplinks for efficient rack-level traffic flow.

NFV and Edge Cloud Service Racks

Telecoms and service providers often deploy dense service racks where host ports, latency and fabric cleanliness all matter. This switch fits NFV and edge-cloud layouts that need 25GbE access into a wider 100GbE fabric.

Planning a Juniper QFX5120-48Y Deployment?

Our team can help design and deploy Juniper QFX5120-48Y switching for data centres, engineering platforms, finance, media production and telecoms racks, with the right uplink plan, resilience model and operating approach for your environment.

Spread the cost of your next IT upgrade or refresh!

Many of our vendor partners offer their own flexible finance programs, available for orders over a certain threshold. 

 

As part of our free consultation and advisory service, we can:

Alternatively, we also work independently with third-party organisations to offer the best possible flexible leasing solutions.

 

Our team is here to help your businesses avoid upfront costs and keep your next IT project on budget. Submit an enquiry today to explore your options.

Trade-in your old IT hardware to save money on your purchase!

Instead of letting unused hardware depreciate or go to waste, our simple IT Asset Trade-In Service helps businesses to regain capital or receive credit towards future purchases.

Our team will assesses the market value of your equipment, managing the entire process from secure collection through to resale or responsible recycling.

To get started, simply submit an enquiry and we’ll respond within 24 working hours.

As a certified partner to industry-leading vendors, we provide access to promotions that reduce upfront spend and accelerate upgrade strategies.

When you work with us, we can bundle and stack multiple offers, navigate application processes, and secure pricing that often isn’t accessible without an official vendor partner.

 

Visit our promotions hub to explore current offers and discuss your eligibility.

Tailored recommendations for your infrastructure

Below you’ll find alternative models, suitable software and services that pair with this solution – helping you to avoid compatibility issues, reduce support overhead and deploy with confidence.

Not sure where to start?

Not all deployments fit standard configurations. If you’re weighing up options or want a second opinion on your setup, our team is here to help with honest, straightforward advice backed by decades of vendor knowledge.

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