Help me understand VDI

[cyr0n_k0r]

Our goals:

Re-purpose existing PC's into a sort of "thin client"
The resources on these PC's will most likely not run windows 7 (we are still on XP) and some models still only have 1GB of ram. Most have 2GB. They are old CPU's and very old hard drives that are slow.. even on XP.

We have LOTS of laptops and are making every effort to replace PC's with newer laptops but there will come a point where we wont have the money to continue replacing PC's, and also even the laptops we are buying now we need to have a long term plan to support them for at least 5-7 years. We are a school district so money is very tight not only right now, but no one is sure when/if things will ever get better again so we need to start thinking creatively to better utilize what we already have.

Our infrastructure:
We currently already user Hyper-V and our domain is 2008 R2. Servers to run VDI are not a problem as we have about 7 or 8 HP G5's that are just sitting around after a physical to virtual migration project that we have completed. 99% of district servers are now virtualized.

We are a Microsoft shop with Active Directory. We are not interested in Linux, Xen, Citrix, Vmware, etc. Our licensing agreement with Microsoft already allows us whatever CAL's we need for whatever server or client scenarios we end up going with.

What I am looking for is the ability to basically have no OS on the machines and network/PXE boot into some kind of WinPE or something that launches a virtual desktop on demand.

The problem with that is I'm not sure how we would accomplish that goal on laptops since a lot of our laptops get taken home at the end of the day both by teachers and students. If that is the case then we need to somehow have something on the machines that is a stripped down or crippled OS that provides only what is necessary to get a student or teacher into their virtual desktop.

Plus, I'm not even sure if that is the best way to go about doing it. Suggestions are most welcome.

We are assuming 100% network and/or internet access for home based scenarios at this time.

 

[Thuleman]

Why do you need/want a VDI in the first place? Which business problem is it supposed to solve?

Seems to me that maintaining all machines via Active Directory & System Center, plus serving out apps for which you only have limited licenses via Terminal Server will be just fine. Why make it more complex than it needs to be by implementing VDI.

It is highly unlikely that your current site license agreement includes a Windows Virtual Desktop license. Those are not CALs, they are different from a licensing perspective and may add substantial cost to your project.

If your site license already includes CALs you are likely far better off with Terminal Services / RDP as needed.

 

[cyr0n_k0r]

Why do you need/want a VDI in the first place? Which business problem is it supposed to solve?.

Actually I think I was pretty clear what I am trying to do. We are a SCHOOL (not a business) and the machines we have will not run windows 7. We can't run windows XP forever.

 

[Netwerkz101]

Actually I think I was pretty clear what I am trying to do. We are a SCHOOL (not a business) and the machines we have will not run windows 7. We can't run windows XP forever.

"Business" need = "SCHOOL" need ... don't get hung up on it.

What Thuleman posted was a very important question considering, by
your own post, you wish to leverage what you already have and not bring
in additional costs or maintenance.

Session Virtualization = Terminal Services = RDS.
- Use this to centralize application access and/or desktop access to end users
- Important to note that this desktop delivery method is based on the server OS. (Win2k*)

VDI
- Use this to centralize client os desktop access for end users.
- Important note that this desktop delivery method is based on a client OS (Windows XP/7)
When you leave out Linux, Xen, Citrix, VMware, and limit yourself to Microsft, regardless of reason (ie budget), you are pretty much stuck with session virtualization.
I know of (read ... no real knowledge) Windows ThinPC ...but IIRC, the endpoint requirements were similar to a regular PC and I don't remember if using it via WAN was an option.
Search for it on Microsoft's site: ThinPC

One thing that comes to mind in your situation is bandwidth for delivering client desktops
across a WAN .... hope your outbound pipe is fat and your users have high speed, low latency connections. Even doing session virtualization via RDP over WAN can be painful.

 

[cyr0n_k0r]

One thing that comes to mind in your situation is bandwidth for delivering client desktops
across a WAN .... hope your outbound pipe is fat and your users have high speed, low latency connections. Even doing session virtualization via RDP over WAN can be painful.

200mbps private fiber cloud site to site links
100mbps metro ethernet Internet

Bandwidth is no concern.

I will look into ThinPC.

So it sounds like the best thing to do is leave the clients on WindowsXP and use that as nothing more than a medium to get clients to their virtual desktops running Windows 7/8

 

[kbrennan]

How many VDI sessions are we talking about?

 

[Thuleman]

the machines we have will not run windows 7. We can't run windows XP forever.

I am not sure I get that. Windows 7 actually performs really well on old hardware. Yes, you do need 1 GB RAM minimum but unless you clog your system up with useless vendor supplied junk and other non-essential stuff Windows 7 should run fine on most machines that run XP.

On the infrastructure odds are that you will need to replace some of the switching equipment with modern switches. It's at times not the bandwidth that kills VDI but the latency.

Also, depending on how many clients you have your storage costs to power all of this could easily be several tens of thousands of dollars.

I'd just hire a consultant to come in and look at this, you can probably get someone who knows their stuff to give you a deal charging like $125/hour for the initial consultation. For 1k they will be able to deliver you some actionable advice that's specific to your environment.