After publishing my Running Nested ESXi, NSX-V or NSX-T on top of NSX-T article which actually turned out to be quite popular, I received an interesting question on whether ENS for NSX-T could also be configured within a Nested ESXi deployment? I was a little familiar with ENS, which I will explain in a second. However, I was not completely sure about the benefits of running ENS in a Nested environment.
With the help from my friend Frank Escaros-Buechsel, who actually works in our NFV group at VMware. Frank helped validate the instructions but he also provided some additional insights on why this could be useful in a lab setup for verifying configuration and behaviors when additional tuning maybe required. If you are NOT running NFV-based workloads, ENS is not something you need to configure when running NSX-T using Nested ESXi.
So what is ENS? Enhanced Network Stack (ENS) also referred to as Enhanced Data Path is an NSX-T capability which was first introduced with NSX-T 2.3. ENS is specifically designed for Network Function Virtualization (NFV) workloads that require a high performance data path. Such workloads include Telco, 5G and IoT based deployments where improved packet throughput is critical for the responsiveness of these applications.