Vcenter not auto generating VM mac addresses as expected.

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Following a copy of some VMs from one infrastructure to another, I seem unable to get the VMs to generate new vCenter Mac addresses with the Runtime ID of each new vCenter instance.


I followed this guide:-

and removed these entries in the VMX file:-


uuid.location =

uuid.bios =

ethernet0.generatedAddress =

ethernet0.generatedAddressOffset =


Now the VM does get a new MAC, but NOT the one with the vcenter ID in it, it gets a different one, something like 00:50:56:9d:52:05 which bears no correlation to the vCenter ID.

ALso instead of being set to “VPX” which would indicate a vcenter generated MAC, this setting gets set to “generated”.

Slightly confused as to how I can force a MAC change allocated by vCenter instead of this “generated” address.
We run dVswitches, do I have to remove the VM from the inventory and re-add? We would lose all the performance data and this might mess up our MABS backups.


Anyone any idea how I can force vCenter to properly allocate a MAC to these VMs with its proper ID?


Thanks, its driving me crazy.

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