What is NX/XD? · Ultra Transcenders glossary

A processor feature that flags areas of memory as not executable. ESX and EVC require it to be turned on in the BIOS.

Also called No-eXecute / eXecute Disable.

In the Ultra Transcenders books

Each book explains NX/XD in context, with comparison tables and the common traps.

ESX
VMware's bare-metal hypervisor, installed on each host in a VCF fleet. Up to version 9.0 it was known as ESXi.
EVC
vSphere cluster capability that exposes the same baseline CPU features on every host, allowing vMotion between different processor generations from the same vendor. A custom EVC mode can be applied to a cluster or to individual VMs.
BIOS
Generation 2 Hyper-V machines use UEFI with Secure Boot; Generation 1 machines rely on this older firmware.