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Hello,
As host i have a Win Server 2008 installed. First I installed three servers and three Windows 7 clients. Now comes the interesting question.
With the servers I would like to build a Windows domain. This includes DHCP and DNS. In addition, I would like to install a PXE service on the new VM I want to install later.
Which is the best in the VB network card settings so that the client and server to see?
What I have not yet understood how the VM can get from the network setting their IP address? Although I have found a DHCP setup, but there is a different IP range than get it the VMs.
Can someone explain to me? Thank you very much

You set up your domain on an internal network. You run your own DHCP and DNS services on your domain controller. You run a router to connect your domain network to the physical network.

It is really very similar to how you run a domain on physical machines. Have you checked out any descriptions of how to do that?