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Assigning Static MAC address to othere VM after Migration (P2V)

 MAC address is not accepting and conflicting , which result its not powering on on destination VC


This issue occurs when the virtual machine has been configured with a static MAC address in the 00:50:56:xx:xx:xx range. VMware vCenter Server 5.1 and later detects this as a protected range and refuses to power on the virtual machine.

In vSphere 5.1 and later new policies have been implemented where the statically assigned MAC addresses can only be in the range 00:50:56:[00-3F]:XX:XX or other non-VMware OUI addresses.

Prefix- and range-based MAC address allocation is supported only in vCenter Server 5.1 or later.

This implies that if you add pre-5.1 hosts to vCenter Server 5.1, and use anything other than VMware OUI prefix- or range-based MAC address allocation, virtual machines assigned MAC addresses that are not VMware OUI prefixed fail to power on their pre-5.1 hosts.
Now, from what we’ve seen, the restriction is a little more detailed than what is described above. Static MAC addresses in vSphere 5.1 must be in the range 00:50:56:[00-3F]:XX:XX. If the MAC addressed is prefixed with 00:50:56 but it is outside of the [00-3F]:XX:XX range, it is still considered invalid and the VM will fail to power on.


We have done some modification into VMX file of Virtual machine. By below change VM will not try to detect Static MAC which is aligned to VM from outside Network with other VM's and because of that VM associated MAC will not conflict with any other and will poweron the VM.

We have added below line in ethernet phase of VMX file by unregister and re-register the VM to ESXi 

ethernet0.checkMACAddress = “false”

After this issue got resolved and VM turn on gracefully.

Refered KB Article 2007042


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