I was wondering if the following MAC address is a valid one?
00:13:74:00:00:00
We have an automated network registration on the system whereby users can plug in their computers and register on the network with a given username/password. Anytime they want to register, the system would detect their MAC and make sure that no one else is using the same MAC under a different username. We have a user who is unable to register because her MAC address "conflicts" with someone else. I was wondering if that MAC is valid in the first place since the first 3 octets recognize vendor and last 3 should be different. I am not sure if all 0s would be fine because that looks too generic. Is is possible that the MAC address could've changed? If so, what are the possible causes of it? Any tips/suggestion and assistance would be appreciated. Thank you.
Best Answer
Can you possibly check the network card and settings of that user? Most probable posibilities are:
1) User changed his mac (knowingly or unknowingly - some download managers do that, to get a new IP via DHCP, etc.).
2) User has a weird/noname/knockoff network card, which doesn't have uniqe MAC addresses. Mostly happenes with cheap Chinese usb ethernet cards (happened to me too, ordered two for ~5usd each, both had the same MAC).
You can also verify if there really is another user with that MAC on the network - it is also possible that it's a parser error.