UNSUPPORTED – Bypass the 8GB RAM limit in VMware Fusion

Note: This is completely UNSUPPORTED, VMware will not support any issues that may arrise from carrying out this change.

Now we have that out of the way…

Whilst building up my homelab I was preparing some vESXi hosts (Nested ESXi http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2009580) and soon realised that I was limited adding a maximum of 8GB per vESXi host.

Fusion 8GB MaxWhilst this is an imposed limit  through the GUI, there is a workaround by amending the VMX file.

From Finder, navigate to your Virtual Machine files, Right Click the file for your Virtual Machine and select ‘Show Package Contents’.

Show Package Contents


From here all the virtual machine files will be displayed, search for the ‘VMX’ file, right click and select open with ‘Text Edit’

Open Text File

Amending the VMX file in Fusion, is the same as ESXi and Workstation. We need to search for the ‘mem size’ field and amend the value inside the quotation marks to our desired values. You will see form the images below, I’ve replaced 2GB with 16GB.

vmx filesSave the change and close Text Edit and Finder and power on your virtual machine in VMware Fusion. You’ll notice when the VM is powered on, that a warning appears stating the machine is configured with an unsupported memory size

VM Power On Warning

Tick the box to ignore the warning and wait for the machine to boot. Once booted you’ll notice your host has the desired amount of RAM….. easy.

ESX console

vi client

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