This is by design in VMware ESXi 5.x/6.0. When using Virtual Hardware versions 8 or earlier, ESXi performs a very strict checking of these extensions unless the virtual machine moves from or to a host with EVC enabled. Virtual Hardware versions 9 and later use more relaxed checking whether EVC is in use or not.
With the strict checking ESXi requires that extensions used by user level applications to match between the source and the destination. The more relaxed checking only requires that the destination should have all the extensions that have been exposed to the virtual machine. In this relaxed mode vMotions are not blocked, if the destination has other ISA extensions which have been not exposed to the virtual machine.
To resolve this issue, you must place either the source or destination host in an EVC-enabled cluster. If you cannot place the source or destination host in an EVC-enabled cluster, you may be able to resolve this issue by upgrading the virtual machine hardware version:
- VMware highly recommends placing the source or destination ESXi host in an EVC-enabled cluster of any processor compatible type. Be aware that the EVC cluster must support the same or a subset of the extensions available in the host you add, and that feature set must be the same or a superset of the extensions the virtual machine expects to use. For information on configuring EVC, see the Migrating Virtual Machines chapter in the Basic System Administration Guide for your ESX release.
- You can alternatively, try to upgrade to Virtual Hardware version 9 (or later) in the virtual machine. Note, however, that this action will not help if the destination host does not support an extension that the VM has been exposed to. There may also be other limitations dependent on your particular environment:
To upgrade the Virtual Hardware version of the virtual machine in the vSphere Client
- Power off the virtual machine.
- Right-click the virtual machine and click Upgrade Virtual Hardware.
To upgrade the ESXi compatibility level (Virtual Hardware version) of the virtual machine in the vSphere Web Client:
- Select the virtual machine.
- Power off the selected virtual machine.
- Select Actions > All vCenter Actions > Compatibility > Upgrade VM Compatibility.
- Click Yes to confirm the upgrade.
- Select the ESXi versions for the virtual machines to be compatible with.
- Click OK.
- Power on the selected virtual machine.
For more information, see Enhanced vMotion Compatibility (EVC) processor support (1003212).