6.7

Table Of Contents
For example, masking the AMD No eXecute (NX) and the Intel eXecute Disable (XD) bits prevents the
virtual machine from using these features, but provides compatibility that allows you to migrate virtual
machines to ESXi hosts that do not include this capability. When the NX/XD bit is visible to the guest
operating system, the virtual machine can use this feature, but you can migrate the virtual machine only
to hosts on which the feature is enabled.
Caution Changing the CPU compatibility masks can result in an unsupported configuration. Do not
manually change the CPU compatibility masks unless instructed to do so by VMware Support or a
VMware Knowledge base article.
Prerequisites
Turn off the virtual machine.
Procedure
1 Right-click a virtual machine in the inventory and select Edit Settings.
2 On the Virtual Hardware tab, expand CPU and select an NX/XD option from the CPUID Mask drop-
down menu.
Option Description
Hide the NX/XD flag from guest Increases vMotion compatibility.
Hiding the NX/XD flag increases vMotion compatibility between hosts, but might
disable certain CPU security features.
Expose the NX/XD flag to guest Keeps all CPU security features enabled.
Keep current Advanced setting values
for the NX/XD flag
Uses the NX/XD flag settings specified in the CPU Identification Mask dialog
box. Enabled only when current settings specify something other than what is
specified in the other NX/XD flag options, for example, if the NX/XD flag bit setting
varies with processor brand.
3 Click OK.
Expose VMware Hardware Assisted Virtualization
You can expose full CPU virtualization to the guest operating system so that applications that require
hardware virtualization can run on virtual machines without binary translation or paravirtualization.
Prerequisites
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Verify that the virtual machine compatibility is ESXi 5.1 and later.
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Intel Nehalem Generation (Xeon Core i7) or later processors or AMD Opteron Generation 3
(Greyhound) or later processors.
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Verify that Intel VT-x or AMD-V is enabled in the BIOS so that hardware assisted virtualization is
possible.
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Required Privileges: Virtual machine.Configuration.Settings set on the vCenter Server system.
vSphere Virtual Machine Administration
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