ESXi vs Full ESX

ESXi vs Full ESX

The future is only ESXi

With the new release of vSphere 4.1 there are some changes and news:

  • the terminology as changed and now ESXi is ESXi Hypervisor Architecture

  • the "old" ESX (or full ESX or legacy ESX or ESX with the service console) is available in the last release, from next version ONLY ESXi will be available.

VMware suggest to migrate to ESXi, the preferred hypervisor architecture from VMware. ESXi is recommended for all deployments of the new vSphere 4.1 release. For planning purposes, it is important to know that vSphere 4.1 is the last vSphere release to support both ESX and ESXi hypervisor architectures; all future releases of vSphere will only support the ESXi architecture.

On how to migrate see:



ESX and ESXi official comparison: - VMware ESX and ESXi 3.5 Comparison - VMware ESX and ESXi 4.0 Comparison

Probably the big difference is that ESXi has a POSIX Management Appliance that runs within the vmkernel and ESX has a GNU/Linux Management Appliance that runs within a VM.

ESX vs. ESXi which is better?

ESXi vs. ESX: A comparison of features

Note that HCL can be differed from ESX and ESXi:


ESXi limitations


Free ESXi (or VMware vSphere Hypervisor 4.1) limitations

  • ESXi 4.x free can not be connected to a vCenter Center (it required a VC agent license)

  • VCB does not work (it require a VCB license)

  • Lot of 3th part backup programs does not work with free ESXi (see also: )

  • RCLI and VMware Infrastructure toolkit are limited to read-only access for ESXi free

  • Free ESXi does not support SNMP

  • Free ESXi does not support Active Directory integration at this time

  • Free ESXi does not support Jumbo Frame -

  • Free ESXi EULA has some interesting restrictions including enforced read only mode for v4 and later versions of v3.5.

See also: What's the difference between free ESXi and licensed ESXi?



ESXi advantages

  • Fast to install / reinstall

  • Can be installed on a SD flash card or USB key (there is also an embedded version that is pre-installed) -

  • Easy to configure (there is a simple configuration menu)

  • Small footprint = fast and easy to patch + (maybe) more secure

  • Extremely thin = fast installation + faster boot

  • Does not use a vmdk for console filesystems (as ESX 4.0 does)

  • There is a tool for dump ESXi configuration

  • Near to be "plug and play" (for example with the embedded version and the Host Profile feature)



Tags (3)

Thanks Andre!

You're welcome.


Hi Andre,

you did another great doc.

I just would add (IMHO) a relevant information related to the vmware support of the esxi usb installations:


Please consider awarding

any helpful answer. Thanks!! -

Por favor considera premiar

las respuestas útiles. ¡¡Muchas gracias!!

Virtually noob blog


I've added the note directly on related document:


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‎10-31-2009 03:07 AM
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