So we're in the middle of a complete IT overhaul, and we're almost finished with most of the infrastructure... And so we start to look at our servers, and visions of Virtual Machines and SANs dance through my head. That said, I've realized that I don't have any real solid idea what resources are needed. Is 1GB enough per vm? 2? 4? What about storage space? processor utilization? Once everything is installed and happy, does my AD Domain Controller REALLY need 2 or more cores dedicated to it? etc.... So, just to be clear, I'm not looking for someone here to magically tell me what I need to buy. I'm simply asking for an idea of where I should look for 'recommended' resource allocations for things like a Domain Controller, Exchange server, mailbox store, SQL database, Blackberry Server, etc.... This is both in the context of a dedicated server, and as a VM... are there going to be problems with the DC sharing CPU cycles with the exchange server, etc....? If we're going to do an overhaul, we might as well do it right, and the first part of that is figuring out what the requirements really are, right?