Juniper QFX5120 Ethernet Switch

Juniper QFX5120 Ethernet Switch

Posted onDecember 16, 2024 December 16, 2024.by Road Runner.Posted inLife

The QFX5120 Switch delivers rich, low latency Layer 2/Layer 3 features and advanced EVPN-VXLAN capabilities, making it an ideal data center top-of-rack and distribution switch for campus enterprise deployments.

Featuring L3 gateway capabilities for routing between virtualized and bare-metal servers, the QFX5120 is designed for extremely agile data centers that require support for overlay/underlay network architectures. Native 25GbE with 100GbE uplink ports on the QFX5120–48Y and QFX5120–48YM, 10GbE/1GbE copper with 100GbE uplink ports on the QFX5120–48T, and 32 100GbE ports on the QFX5120–32C make the QFX5120 family ideal for spine-and-leaf network deployments.

QFX5120–48Y

The QFX5120–48Y is a 25GbE/100GbE data center leaf and campus distribution switch featuring:

• 48 25GbE (SFP28)/10GbE (SFP+)/1GbE (SFP) downlink ports
• Eight 100GbE (QSFP28)/40GbE (QSFP+) uplink ports
• Up to 2/4 Tbps (uni/bidirectional) of L2 and L3 performance, with latency as low as 800 nanoseconds
• A 2.2 GHz quad-core Intel CPU with 16 GB memory and 50 GB SSD storage

Using breakout cables, each of the eight 100GbE QSFP28 ports can be broken into four 25GbE SFP28 ports, while each 40GbE quad small form-factor pluggable plus (QSFP+) transceiver ports can be broken into four 10GbE small form-factor pluggable plus (SFP+) transceiver ports, increasing the total number of supported 25GbE and 10GbE ports per switch to 80.

Product Options

The QFX5120 Switch includes four compact 1 U platforms — the QFX5120–48Y, the QFX5120–48YM, the QFX5120–48T, and the QFX5120–32C — that provide wire-speed packet performance, very low latency, and a rich set of Junos® operating system features.

QFX5120–48T

The QFX5120–48T is a 10GbE/100GbE data center leaf and campus distribution switch featuring:

• 48 dual-speed 1GbE/10GbE RJ-45 copper downlink ports
• Six dual-speed 100GbE (QSFP28)/40GbE (QSFP+) uplink ports
• Up to 1.08/2.16 Tbps (uni/bidirectional) of L2 and L3 performance, with latency as low as 800 nanoseconds
• A 2.2 GHz quad-core Intel CPU with 16 GB memory and 100 GB SSD storage

Using breakout cables, 40GbE QSFP+ ports 50 and 51 can be channelized into four 10GbE SFP+ ports each, increasing the total number of 10GbE ports per switch to 56.

Product Description

The Juniper Networks® QFX5120 Switch delivers high scale, high availability, and high performance for data center and campus deployments. The QFX5120 Switch is a versatile routing and switching platform addressing higher server access speed and campus distribution use cases while offering high-density 1GbE/10GbE/25GbE and 100GbE uplinks for collapsed spine data center or campus distribution deployments.

QFX5120–48YM

The QFX5120–48YM is a 10GbE/25GbE/100GbE data center leaf and campus distribution switch featuring:

• 48 25GbE (SFP28)/10GbE (SFP+)/1GbE (SFP) downlink ports
• Eight 100GbE (QSFP28)/40GbE (QSFP+) uplink ports
• Up to 2/4 Tbps (uni/bidirectional) of L2 and L3 performance, with latency as low as 800 nanoseconds
• Media Access Control Security (MACsec) AES-256 support across all ports
• A 2.9 GHz quad-core Intel CPU with 16 GB memory and 100 GB SSD storage

When using breakout cables, two of the 100GbE QSFP28 ports (ports 50 and 52) can be broken into four 25GbE SFP28 or four 10GbE SFP+ ports, increasing the maximum number of 10GbE/25GbE ports supported to 56. When using breakouts, the total number of all ports on the switch, including 6x100GbE ports and 56×10/25GbE, is 62.

QFX5120–32C

The QFX5120–32C is a compact 100GbE data center leaf-and-spine and campus distribution switch featuring:

• 32 100GbE (QSFP28) or 40GbE (QSFP+) uplink ports
• A 2.2 GHz quad-core Intel CPU with 16 GB memory and 64 GB SSD storage
• Up to 3.2/6.4 Tbps (uni/bidirectional) L2 and L3 performance, with latency as low as 800 nanoseconds

Using breakout cables, 100GbE QSFP28 ports 0–30 can be channelized into four 25GbE SFP28 ports*, and the 40GbE QSFP+ ports 0–30 can be channelized into four 10GbE SFP+ ports, increasing the total number of 25GbE per switch to 124 and the total number of 10GbE ports per switch to 126 (including SFP+ ports 32 and 33). Port 31 does not support 4x10G or 4x25G channelization options. Only 100GbE, 40GbE, and 2x50GbE channelization options are supported on port 31.

In addition, all QFX5120 switch models include:

• Support for VXLAN as an L2 or L3 gateway
• Advanced Junos OS features such as Ethernet VPN-Virtual Extensible LAN (EVPN-VXLAN), BGP add-path, L3 VPN, and MPLS
• Feature-rich automation capabilities with support for Python and zero-touch provisioning (ZTP)

Junos OS

The high-performance QFX5120 Switch runs Junos OS, Juniper’s powerful and robust network operating system that powers all Juniper switches, routers, and firewalls. Key Junos OS features that enhance the functionality and capabilities of the QFX5120 include:

• Software modularity, with process modules running independently in their own protected memory space and with the ability to do process restarts
• Uninterrupted routing and forwarding, with features such as nonstop active routing (NSR) and nonstop bridging (NSB)
• Commit and rollback functionality that ensures error-free network configurations
• A powerful set of scripts for on-box problem detection, reporting, and resolution

Data Center Deployments

Data centers demand high-speed, low-latency, storage- and I/O-converged networking solutions that maximize performance for physical servers, virtual servers, and storage. The QFX5120 Switch addresses these issues with low-latency, lossless, high-density 10GbE, 25GbE, and 100GbE interfaces on a compact 1 U platform. In addition, the QFX5120 offers EVPN-VXLAN L2 and L3 gateway support, making it an ideal solution for either edge routed or centrally routed overlay deployments in the data center. The QFX5120 also supports flexible back-to-front and front-to-back airflow cooling options, ensuring consistency with server designs for hot-aisle or cold-aisle deployments.

Data Center Server Access

The QFX5120–48Y and QFX5120–48YM support tri-speed 1GbE/10GbE/25GbE, making them a perfect fit for top-of-rack deployments. The 48 ports of native 10GbE/25GbE for server connectivity, plus up to eight 40GbE or 100GbE ports for uplink connectivity, provide very low oversubscription of 1.5:1 from access to aggregation.

The QFX5120–48T supports dual-speed 1GbE/10GbE, also making it a perfect fit for top-of-rack deployments. The 48 native 10GbE RJ-45 copper ports for server connectivity, plus up to six 40GbE or 100GbE ports for uplink connectivity, provide an unsubscribed (0.8:1) access-to-aggregation ratio.

The QFX5120–32C can also be used for high-density 25GbE server connectivity, with an option to break out the 100GbE ports into four 25GbE ports.

In Figure 1, the QFX5120 is deployed as a leaf acting as an edge-routed gateway. In this topology, the VXLAN tunnel encapsulation and decapsulation take place on the QFX5120 leaf switches, while Juniper Networks QFX5200–32C or Juniper Networks QFX5210–64C spine switches are used for IP transit. Juniper Networks QFX5110–32Q switches can also be used in the spine to build a 40GbE fabric.

Figure 1: Edge-routed bridging at the leaf with QFX5120 as leaf switches and QFX5200–32C/QFX5210–64C as spine switches

In Figure 2, the QFX5120–48YM leaf and Juniper Networks QFX10008 Switch spine are deployed as EVPN-VXLAN switches acting as centrally routed gateways or distributed edge-routed gateways. If centrally routed bridging is used, the VXLAN tunnel encapsulation and decapsulation occur on the spine switches for inter-IRB (integrated routing and bridging) symmetric routing purposes. If edge-routed bridging is used, the IP first hop gateways are distributed at the leaf-level QFX5120–48YM switches using Type 5 symmetric inter-IRB routing. When using a QFX10000–30C-M MACsec line card installed in a spine QFX10008 Switch working with a leaf QFX5120–48YM switch, the leaf-to-spine architecture offers end-to-end MACsec AES-256 capabilities.

Figure 2: QFX5120–48T and QFX5120–48Y/48YM as leaf and QFX10000 as spine switches

Data Center Spine

The QFX5120–32C, with 32 ports of 100GbE, can serve as the spine in small to medium-sized enterprise data centers. The QFX5120–32C can be deployed in a three-stage IP Clos with EVPN-VXLAN overlay to support as many as 1500 server access ports. The QFX5120–48Y/QFX5120–48YM and QFX5120–32C can also be used as a collapsed spine data center deployment, offering Ethernet segment identifier-link aggregation group (ESI-LAG) connectivity to the rest of the network infrastructure blocks.

All QFX5120 switches can operate in both cut-through and store-and-forward modes, delivering sustained wire-speed switching with sub-microsecond latency and low jitter for any packet size (including jumbo frames) in either mode. With features such as multichassis link aggregation (MC-LAG), the QFX5120 supports active/active server dual-homing and can use full bisectional bandwidth from server to switch.

Equipped with Junos OS, the QFX5120 supports the most advanced and robust routing capabilities in the industry, OSPF for both IPv4 and IPv6, as well as advanced routing capabilities such as IS-IS and BGP. With additional capabilities such as 64-way equal-cost multipath (ECMP) and BGP add path, the QFX5120 is an ideal building block for deploying the most robust L3 underlay for SDN.

Campus Deployments

Juniper campus fabrics provide a single, standards-based Ethernet VPN-Virtual Extensible LAN (EVPN-VXLAN) solution that can be deployed in any campus, whether a two-tier network with a collapsed core distribution or a campus-wide system that involves multiple buildings with separate distribution and core layers.

The QFX5120–48Y and QFX5120–48YM are ideal as campus distribution switches with 10GbE/25GbE downlinks and 40GbE/100GbE uplinks supporting technologies like MC-LAG and EVPN multihoming.

The QFX5120–32C is ideal as a campus core switch with 32 ports of 100GbE and support for technologies like campus fabric core-distribution.

The QFX5120–48T supports dual-speed 1GbE/10GbE, also making it a perfect fit for top-of-rack deployments in campus environments for server connectivity.

Juniper campus fabrics support the following validated architectures:

• MC-LAG and EVPN Multihoming (Collapsed Core/Distribution): A pair of interconnected QFX5120 switches can be deployed to provide EVPN multihoming (ESI-LAG) or multichassis link aggregation (MC-LAG) in a collapsed core/distribution configuration. This eliminates the need for Spanning Tree Protocol (STP) across the campus network by providing multihoming capabilities from the access to the distribution layer, while distribution to the core is an L3 IP fabric. ESI-LAG also supports horizontal scaling with more than two devices in the distribution layer and can extend EVPN to the core.
• Campus Fabric Core-Distribution: A pair of interconnected QFX5120 switches can provide EVPN L2 and L3 VXLAN gateway support. This eliminates the need for STP across the campus network by providing a multihoming capability from the access to the distribution layer, while distribution to the core is an L3 IP fabric using EVPN technology. The IP fabric can also extend to connect multiple enterprise buildings, while VXLAN allows stretching of L2 across buildings. An IP Clos network between the distribution and the core layers can exist in two modes, both of which are supported by the QFX5120:
• Centrally routed bridging overlay: An IRB interface placed at a central location in the fabric (in this case, a core device)
• Edge routed bridging overlay: An IRB interface placed at the edge of the fabric (in this case, a distribution device)
• Campus Fabric IP Clos: The Campus Fabric IP Clos architecture pushes VXLAN Layer 2/3 gateway functionality to the access layer. In this architecture, the QFX5120 switch acts as an IP fabric distribution switch.