I have one server running one virtual machine. The virtual machine is an exchange server. Other services are AD, DNS, hyper-v, DHCP, Fileserver and an FTP server. I have issues with the server and Im about to reinstall and while I do that I want to make it right this time. I see 2 installation scenarios taking place. First is the parent installed with windows 2008 core, Ive already posted one question about where to put the roles (http://forums.technet.microsoft.com/en-US/winservercore/thread/cbecce82-d1e7-44a0-90cb-b598601311bc). But for this planning question, lets say the parent should only run hyper-v. I then need to create a virtual win 2008 full installation server for the other services. As well as my exchange server. Thats 3 machines total. Second scenario would be a full win 2008 installation with all the roles mentioned enabled including hyper-v, and one virtual machine being the exchange server. I know ms I recommending the first scenario. But in my mind, first scenario gives me 3 machines and second only 2. Less over head or not, a whole virtual server extra seems not to be as efficient as the second option. Or am I missing something?What about core installation only running hyper-v and fileserver. Another virtual core running AD, DNS, DHCP and FTP. A third virtual machine running ftp and then my virtual exchagne server?

Hello, Firstly, please let me explain it in a little more detail, why we recommend putting all the services into virtual machines rather than in the root OS (running in parent partition). This is not only for performance consideration, but also for security and reliability considerations. The parent partition is used for configuring and managing all of the virtual machines, managing and assigning hardware devices. It contains the virtualization stack where all the VMs' relevant components are actually running (including virtual devices). You can simply think the virtualization stack as the monitor or manager of all the virtual machines. So, if you put any other services in the parent partition and if these services encountered any problems (such as performance issue), that may impact the virtualization stack, which in turn impacts all the virtual machines. That means one problem in the service may cause all other services stop working. However, if you put these services separately into the virtual machines, and if one service corrupted or even one virtual machine corrupted, other services running in different virtual machine will not be affected. Selecting the Server Core installation would be a good choice. But as I mentioned previously, you may also put services into virtual machines to prevent potential problems. Best regards,Chang Yin