This will be a quick post to try and address a couple of the VCP-NV objectives:
1. Define Benefits of Running VMware NSX on Physical Network Fabrics
2. Describe Physical Infrastructure Requirements for a VMware NSX Implementation
NSX, as a solution, is part of a software-defined datacenter model. This is moving away from a traditional hardware-defined datacenter model. The hardware defined datacenter is where you have racks of servers, switches, routers etc, which all have one or multiple jobs to carry out. This is a model we’re used to, however is one that has limitations in that it can be slow and costly to change, grow and evolve the services it provides.
Software-defined datacenter solutions take away the direct link between the hardware and the service being provided. It will allow services to run on any hardware/storage/networking devices. NSX, for example, requires only layer 2 switching and L3 IP routing to be available at the hardware layer. These basic services can be provided by any networking hardware, whilst NSX itself will then provide the more advanced features. Because these advanced services are created in a software layer rather than on the hardware devices, it makes for a much more agile datacenter which is capable of responding quickly when change is required.
As NSX requires only L2 and L3 services it can be used now, with existing datacenter networking equipment. NSX runs within ESXi, so is independent of the physical networking hardware in the DC. So long as the ESXi hosts have appropriate L2/L3 connectivity, then NSX can function, and logical L2 and L3 services can be created and provided to virtual machines.