VMware ESX v.s. ESXi Explained
VMware ESX and ESXi provide a virtualization layer that abstracts the processor, memory, storage and networking resources of the physical host into multiple virtual machines. ESX and ESXi are bare-metal hypervisors that create the foundation for a dynamic and automated data center. ESX com in two main versions:
ESXi:
- Managed through either a BIOS-like direct console or vSphere command-line interface vCLI
- A high-security, small disk footprint
- ESXi installable – Available as an installable CD or DVD boot image
- ESXi Embedded – ESX image preinstalled as firmware or burned onto an external USB key by the hardware vendor
- ESXi is a virtualization platform that does not contain a service console. It has a small disk footprint for added security and reliability. ESXi is available in two forms: ESXi embedded and ESXi Installable.
ESX:
- Managed through either a built-in service console or vCLI
- Will not be supported in next version of vSphere
ESXi embedded is software that is preinstalled as firmware in a server’s physical hardware or burned onto an external USB key by the hardware vendor. Moving ESXi Embedded USB keys from one server to another is not supported. ESXi Installable is software that is available as an installable CD or DVD boot image. You install the ESXi Installable software onto a server’s hard drive.
In the ESX/ESXi architecture, applications running in virtual machines access CPU, memory, disk and network interfaces without direct access to the underlying hardware. The ESX/ESXi hypervisor is called the VMkernal. The VMkernel receives request from virtual machines for resources from the virtual machine monitor VMM and presents the requests to the physical hardware.
An ESX/ESXi host can be accessed through several interfaces, including:
- The VMware vSphere client
- vCLI VMware vSphere commandline
- vSphere API/SDK
- Common Information Model CIM
CIM is a management standard that is promoted by the distributed management task force. Much of the information that you find through the CIM interface is also available through the vSphere API. But some information can be found only through CIM, including the health status of the hardware hosting ESX/ESXi. ESX and ESXi is supported on Intel processors, Xeon or Opteron processors. ESX/ESXi includes a 64-bit VMkernel. Hosts with 32-bit only processors are not support. ESX/ESXi offers support for both 32bit and 64bit guess OS.