Home » VMware » VCP510 » Which two actions will minimize the effect of these differences?
An administrator has a mixture of Intel-based ESX Hosts in a DRS cluster where the CPUs are compatible in every way except that some support the NX/XD feature and some do not.
Which two actions will minimize the effect of these differences? (Choose two.)
A. Mask the NX/XD bit in the Processor section of the Configuration tab on the ESXi hosts
B. Mask the NX/XD bit on every virtual machine in the cluster
C. Enable Enhanced VMotion Compatibility
D. Enable Rapid Virtualization Indexing
Correct Answer: BC
Explanation/Reference:
Since we do not have the option to disable it on the host you would hide it on the VM’s just as the following states:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1993#modnxxd
Modifying the default NX/XD mask
Issues with the NX/XD features on CPUs are common. Ensure that the feature is either enabled (or disabled) in the BIOS of all hosts to avoid these compatibility error messages.
Note: Not all servers have the option to disable or enable NX or XD in the BIOS.
If a CPU feature compatibility issue with the NX/XD bit is encountered, an error similar to this is generated:
The CPU of the host is incompatible with the cpu feature requirements of virtual machine; problem detected at CPUID level 0×80000001 register ‘edx’.
Power off the virtual machine before modifying the NX/XD mask.
To modify the mask to enable or disable the NX/XD CPU bit:
Navigate to the CPUID Mask option on the virtual machine Options tab (see steps above, if necessary).
Select Hide the NX flag from guest to disable the CPUCompatibility check for the selected virtual machine,or Expose the NX flag to guest to enable this CPU compatibility check for the selected virtual machine.
Click OK to save the change.
Incorrect: Mask the NX/XD bit in the Processor section of the Configuration tab on the ESXi hosts
Explanation: The NX/XD bit is masked at the virtual machine level.
Incorrect: Enable Rapid Virtualization Indexing
Explanation: Rapid Virtualization Indexing will have no effect on Intel-based hosts since it is an AMD feature.
