what is esx host
VMware ESXi (formerly ESX) is an enterprise-class, type-1 hypervisor developed by VMware for deploying and serving virtual computers. As a type-1 hypervisor, ESXi is not a software application that one installs in an operating system; instead, it includes and integrates vital OS components, such as a kernel.After version 4.1, VMware renamed ESX to ESXi.MWare dropped development of ESX at version 4.1, and now uses ESXi, which does not include a Linux kernel. The vmkernel is a microkernel with three interfaces: hardware, guest systems, and the service console (Console OS).