Cisco Nexus 9396PX 40G Spine-Leaf Netowrk Solution

Updated on May 4, 2023

Change in data center has never stopped. It has been proved that 10G can no longer keep up with the increasing Ethernet needs driven by applications like virtual data center and Cloud. Data centers are forced to migrate to 40/100G or higher data rate. The devices including switches, optics and cables in data center should be replaced to support higher data rate. Meanwhile, the network architecture is also required to be optimized to adapt the continuous changing needs of data center and achieve higher cabling density.

Currently a new architecture is replacing the traditional three-tiered network architecture, which is known as leaf-spine architecture. Devices that can support such network architecture is also available. For example, Cisco Nexus 9396PX switch, one of the first member of the Cisco Nexus 9000 series platform, can support data rate of 40G with low power consumption and outstanding performance in this optimized network architecture. This post will introduce how to connect Cisco Nexus 9396PX in leaf-spine architecture.

FS Test Assured Program

Advantages of Spine-leaf Architecture

Spine-leaf architecture has various advantages over the traditional tree-tiered architecture. Some of them are described here. As shown in the above below, in a spine-leaf network architecture, every leaf switch is required to be connected to every spine switch, which can create high density cabling environments depending on the scale of the network. As it shows that a spine-leaf architecture uses a two-tier mode, which can reduce the overall signal latency through the elimination of a switching layer. Meanwhile, the ability to expand capacity can be increased largely and easily with this architecture. For instance, an additional Spine switch may be added and uplinks may be extended to every Leaf switch, resulting in the addition of interlayer bandwidth and reduction of the oversubscription.

spine-leaf vs 3-tier

Using Cisco Nexus 9396PX as Leaf Switch

The Cisco Nexus 9396PX is a 2RU non-blocking Layer 2 and 3 fixed switch offering 48 ports of 1G SFP/10G SFP+ and 12 ports of 40G QSFP+. The above picture shows the port information of Cisco Nexus 9396PX. Cisco Nexus 9396PX is suggested to be used as leaf switch in 40G spine-leaf network. In spine-leaf network architecture for 40G application, the connections between the spine switches and leaf switches are 40G, while connections between the leaf switches and servers are usually 1/10G. Thus these 40G QSFP+ ports can be used to connect the spine switch and the 1G SFP/10G SFP+ are suggested to connect servers and routers. To accomplish the whole spine-leaf connection, optics and cables or DAC (direct attach cable) should be used. The following picture shows a 40G spine-leaf architecture with Cisco Nexus 9396PX being used in the leaf layer and the cabling choice for Cisco Nexus 9396PX switch in this architecture.

Cisco-Nexus 9396PX 40G spine-leaf connection solution

Cisco Nexus 9396PX Spine-leaf Cabling Solution

Using the Cisco Nexus 9396PX in 30G spine-leaf network architecture, the network cabling density can be increase effectively and the network is more adaptable to the continuously changing needs. The following is the related products for Cisco Nexus 9396PX connection in 40G spine-leaf network.

Connection Option 1: Optics & Cable Option 2: DAC
Spine to leaf (40G connection) QSFP-40G-SR4 MMF, OM3/OM4, MPO patch cable QSFP-H40G-AOC (1m to 10m are available) QSFP-H40G-CU (1m to 5m are available) QSFP-H40G-ACU (7m to 10m are available)
QSFP-40GE-LR4 SMF, LC duplex patch cable
Leaf to server (1/10G connection) SFP+ Optics   SFP-10G-AOC (1m to 10m are available) SFP-H10GB-CU (1m to 5m are available)
SFP-10G-SR MMF, LC duplex patch cable
SFP-10G-LR SMF, LC duplex patch cable
SFP Optics  
GLC-T RJ-45, Cat 5
GLC-SX-MMD MMF, LC duplex patch cable
GLC-LH-SMD SMF, LC duplex patch cable

All the products mention in this chart can be customized according to your application in Fiberstore (FS.com) and are fully tested before they go to the market. Kindly contact sales@fs.com for more details, if your are interested.

You might be interested in