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Is it possible to assign an arbitrary MAC address to an VirtualBox virtual machine instance? This answer suggests that it is only possible to generate MAC addresses where the most significant byte is a multiple of 2.

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Downvoters, please leave a comment stating why you think this is a such a bad question. Maybe I can improve it – knittl Apr 9 '12 at 9:11

I have no idea where you got the idea that any part of a MAC address had to be a power of two from that answer... it only specifies that the first octet has to be even, which isn't a virtualbox limitation, it's an Ethernet one (if that bit is '1', it's a multicast address). The comments on that answer explain this. Feel free to try to assign such an address if you like, but don't expect anyone to do anything other than point and laugh when you tell them it doesn't work.

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Oh, I mixed up nibbles and bytes (I read the regex wrongly). Okay, a "multiple of 2" (again, I was too fast reading that regex) – knittl Apr 9 '12 at 7:41
You've still got the regex wrong (it's the MSB, not the 2nd MSB), and my answer still stands. – womble Apr 9 '12 at 7:42
Hm yeah. That also comes from the fact, that I mixed up nibbles (characters in the regex) and bytes (pairs of chars in the regex) – knittl Apr 9 '12 at 7:44
So, do you understand why that restriction is in place? – womble Apr 9 '12 at 7:47
No not really. The wikipedia article on MAC addresses states that the broadcast MAC address is all bits 1 (FF-FF-FF-FF-FF-FF). For multicasts your claim seems to be true however. I think I understand now, thanks! – knittl Apr 9 '12 at 7:55

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