Month ago I installed SBS 2011 in a virtualized environment, in Hyper-V role of Windows 2008 R2 server to be exact. As all of you already know, week ago SP1 RTM for R2 server was released and I have installed it on my Hyper-V host. At the same time, I upgraded all my guest OS operating systems to SP1 as well. later on, all guest operating systems where upgraded with new Hyper-V integration components which was a needed step to start utilizing Dynamic Memory. All guest machines happily took on new settings and started using this new feature of Hyper-V. All but SBS 2011 Standard server.
SBS 2011 Standard is supported in virtualized environment, as it is clearly stated in deployment guide:
Installing SBS 2011 as a guest inside a HyperV server parent is fully supported. Installing the HyperV role ON SBS 2011 is not. With the premium add on you can take the Windows Server 2008 R2 standard media and install it as a base for the HyperV role. Then you are licensed to install the SBS 2011 media AND the Windows Server 2008 R2 media as guests inside the Windows 2008 R2 server that you installed the HyperV role. This is referred to as 1+1 licensing and is a supported deployment of SBS 2011. Installing SBS 2011 as a guest inside _any of the virtualisation platforms certified for Windows Server 2008 is fully supported. SBS11 on Hyper-V has an advantage in that there is no delineation of ‘our problem’ vs ‘their problem’ in regard to host/guest operation.
But, for some reason, SBS 2011 is totally ignorant to the Dynamic Memory settings of Hyper-V role. Personally, I do not see a valid reason for it, since SSB 2011 is based on Windows Server 2008 R2 Standard edition which can be and is upgraded to SP1. Of course, when you read Hyper-V Dynamic Memory Guide, there is no mention of SBS 2011 as supported operating system.
I hope that it will be rectified in one f the future patch releases. Until then, I am stuck with fixed size RAM in my SBS 2011 virtual machine.