The network architecture employs a VLT connection between the two ToR switches. In a non-VLT environment, redundancy requires idle equipment, which drives up infrastructure costs and increases risks. In a VLT environment, all paths are active, adding immediate value and throughput while still protecting against hardware failures. VLT technology allows a server or bridge to uplink a physical trunk into more than one Dell Networking switch by treating the uplink as one logical trunk. A VLT-connected pair of switches acts as a single switch to a connecting bridge or server. Both links from the bridge network can actively forward and receive traffic. VLT provides a replacement for Spanning Tree Protocol (STP)-based networks by providing both redundancy and full bandwidth utilization using multiple active paths. The major benefits of VLT technology are:
Each Dell Networking S5248F-ON switch provides six 100 GbE uplink ports.
The remaining 48 ports of 25 GbE are used for server connectivity. An Openshift Container Platform cluster with up to 20 server nodes can easily be accommodated using a pair of S5248F-ON switches. Expansion of an Openshift Container Platform single-rack cluster beyond 20 nodes is managed in one of two ways: add a pair of aggregated S5248F-ON switches or select Dell EMC Networking S5232F-ON switches.
The S5232F-ON switch also supports ONIE for zero-touch installation of network operating systems. In addition to 100 GbE Spine/Leaf deployments, the S5232F-ON switch can also be used in high density deployments using breakout cables to achieve up to 128 x 10 GbE or 128 x 25 GbE ports.
The following figure shows the switch connectivity.
Figure 9. Switch connectivity
The VLT configuration involves the following high-level steps: