With the increasing use of virtual machines in my environment, I am needing more and more unique mac addresses to assign to the many virtual Ethernet devices I have attached and visible to my non-virtual physical network. The problem of course is that I don't have an IEEE OUI and therefore can't generate guaranteed to be unique addresses, and while the possible address space is quite large, it occurs to me that there should be something - ala rfc 1918 - for this kind of situation. For now however, I just want to know if anyones got something better than 'pick an oui out of the air' or 'pick an old dead manufacturer oui', or worse, 'pick old 10base2 network cards and destroy them, saving the mac'. In the future however, I think there's going to need to be some sort of extension or modification to dhcp to accomodate virtual machines in this regard (of not having a manufacturer assigned addresses for the virtual ethernets). Mike-