Hello Sami19861987,

It's a good question, but one that should be asked to the software manufacturer.

But if we want the question is a little more messy, in the sense that in versions prior to ESXi / vCenter 8.0U2 what from the point of view of a vCenter object is a MAC address whose assignment is as "automatic" from the point of view of the GUI of a HOST running ESXi it's as "assigned" MAC Address NOT an "automatic" one but with this latest recent version things have changed in such a way that it is not at all difficult to cause a series of other messes and consequent problems, that is, it is no longer so true.

As you have seen via the GUI of a vCenter object version 8.0U2, the option to assign a MAC Address manually or vice versa does not work. So you might think about getting around the problem by intervening from the GUI of the HOST on which that virtual machine resides, IMHO DO NOT DO THIS if you plan on manually returning to an automatic assignment later, at least NOT with a HOST running ESXi 8.0U2.

I just noted that a standalone HOST running ESXi version 8.0U2 when creating a VM automatically assigns by default a so-called "impermissible static ethernet address 00:0c:29:xx:yy:zz" which, when that host will be subsequently added to inventory of a vCenter object versione 8.0U2 the circumstance is verified and results in an impediment to start/restart of the affected virtual machine.

I can't say if there are other combinations potentially capable of producing other similar results, but I was able to easily reproduce some of them using what the GUIs allow. If there was a channel to report potential BUGS or product defects, it can happen (and I understand it), I would have used those instead of the forum.

Regards,
Ferdinando

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