Virtual machines

If you want to detect virtual machines in the network, you can create smart maps defining filters:

Primary MAC address / starts with / <type the first three octets from the list below>

If, on the other hand, you want the network scanner/rescanner not to detect virtual machines (e.g. due to exceeded limit of devices allowed by the license), add the first three octets from the following list, each followed by an asterisk, to the ignored addresses list (in the Atlas properties).

Virtual PC

http://blogs.technet.com/b/medv/archive/2011/01/24/how-to-manage-vm-mac-addresses-with-the-globalimagedata-xml-file-in-med-v-v1.aspx

VMware
http://technet.microsoft.com/en-us/library/jj590655.aspx

Hyper-V

http://technet.microsoft.com/en-us/library/jj590655.aspx

VirtualBox

https://forums.virtualbox.org/viewtopic.php?f=1&t=26295