Prior to Vista (2003, XP) Windows had a key in the registry
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\dmio\Boot Info\Primary Disk Group
which indicated which dynamic disk group is imported/active on this installation.
Since Vista, this key is gone. Still, the OS needs to store that info in some way, since the same disk group, when imported on another machine won't auto import again (i.e. if the dynamic disks are on a SAN, each time a Vista boots, other Vistas see the disks as foreign).
My question in short is - where is this information (Primary disk group for this machine) stored in Vista