The VM hardware version designates the virtual hardware functions supported by a virtual machine, which relates to the hardware on the host server. A VMware product will not be able to power on a VM with a hardware version higher than what it supports.
Having the wrong hardware version for your hypervisor can lead to issues moving VMs between differing versions of ESX and/or Fusion and restrict the ability to edit the specific VMs settings within the Vsphere HW client. VMware have published a full vmware hardware version compatible matrix of ESXi hosts and compatible virtual machine hardware versions.
To get round this you need to change the hardware version within the VMs .vmx file. In ESX this is stored within the VMs folder in the datastore (/vmfs/volumes/ds2/vm_name/). In fusion hold alt and right-click on the VM, will have an option Open Config File in Editor.
1. Before editing the hardware version you should unregister the VM (by referencing its vmid) and create a copy of the current vmx file in case you screw it up. Alternatively from the GUI right click and choose unregister.
List all the registered VMs to get VMIDvim-cmd vmsvc/unregister vmidcp /vmfs/volumes/ds2/vm_name/vm_name.vmx /vmfs/volumes/ds2/vm_name/vm_name-copy.vmx
2. Use vi to edit the hardware version number within the .vmx file. For example virtualHW.version = “13” is ESX 6.5 and virtualHW.version = “10” ESX 5.5. You can always check what version existing machines are if unsure.
To do this in Fusion hold alt, right-click on the VM and choose Open Config File in Editor
3. Re-register the VM by referencing the VMs .vmx file.
4. Obtain the Inventory ID (VMID) for the virtual machine and start it
vim-cmd vmsvc/getallvmsvim-cmd vmsvc/power.on
vmidvim-cmd vmsvc/reload vmid If need to restart a vmdel /vmfs/volumes/ds2/vm_name/vm_name-copy.vmx Delete the backup if VM worked as planned
If the Guest operating system template is wrong this can also be changed within the .vmx file. For example ESX 6.5 uses centos 64bit whereas in 5.5 it uses other 32bit. Edit the guestOS dictionary in the .vmx file.
guestOS = other
Centos64 bit guest OS on ESX5.5guestOS = centos-64 Centos64 bit guest OS on ESX6.5