Virtual Server: VS2005R2 is not detecting NICs added after the installation of VS2005R2

The issue that I was seeing was that after installing Virtual Server 2005 R2, I had subsequently added a NIC to the system. The host OS had correctly detected the NIC, and I installed the latest drivers. The problem was that the Virtual Server 2005 R2 interface was not displaying the new NIC in the interface. Just to confirm that I wasn't missing something, I tried adding a new virtual network (click Virtual Networks>Add>Network Adapter on Physical Computer), but when I went to select my physical adapter, only one adapter was being displayed.

After that I searched around and found that Mark was having similar symptoms, albeit not in an identical situation. Since the virtual machine that I needed to have running was needed for a beta test immediately, I didn’t want to uninstall/reinstall Virtual Server 2005, so I decided to look around a bit more in the interface.

Noticing the network adapter "Internal" (Virtual Networks>Configuration>Internal), I took a look at its configuration. This internal adapter had no physical NIC selected, but when I used the drop down window I found that the new NIC I had recently added was being displayed as an option. After that it was just a matter of changing the physical network adapter from none, to the new one, and re-adding a new "internal" adapter. After doing that, I then changed my Network Configuration section from the Virtual Server Interface on the virtual machine that needed to use this connection (while the virtual machine was offline). Finally, when I turned the virtual machine back on, it detected my new physical NIC, and I was then able to configure it.

Hypervisor: Status update

Back in a post from earlier this year, I talked about some of my thoughts on Microsoft’s hypervisor layer of technology being built into Longhorn for virtualization. At the time there was really very little to go on publicly, beyond a commitment to improve virtualization technology in Windows products, and some older research material on virtualization technology in general.

Since then, it looks like quite a bit has happened. First of all, this webcast is really worth checking out. If you’re specifically interested in the hypervisor layer, jump to minute 43.15 and start listening. But to hit the basics, it looks like I was at least in the right ball-park with my with my initial take, or if not my initial take, then at least with some of my wish-list items.

My understanding is that the microkernelized hypervisor is a thin layer of software that sits just below the host operating system to interact with the hardware. This is notably different then the way Virtual Server 2005 exists today, where the vmm.sys sits architecturally at the same layer as the kernel of the host OS. From a functional standpoint, this should improve reliability and reduce or eliminate the potential for something happening on the “host” to bring down the hypervisor layer, and thus crash all guest operating systems

So what’s happening at the hypervisor layer? Well, some very basic core functionality, with an emphasis on dependability; which makes me wonder if we’ll see something like Microsoft’s Singularity doing work here. If you haven’t heard of Singularity, check out this link for a PDF of material related to the effort. The short of it, is that it’s a research project which has a goal of demonstrating practical new technologies which improve dependability. Sounds just like what we’d want in the hypervisor layer.

Step back for a minute and think about the implications of this. We’ve already heard that Longhorn is going to include something called the “Windows Server Core”. Which is really taking the concept of “roles” that were introduced in Windows Server 2003, and extending that concept out. In other words, we’ll be able to deploy a “Windows Server Core” with say, IIS. What that means is that the server core will be deployed to the bare-metal, as well as TCP/IP, and IIS. We won’t get a GUI, we won’t get unnecessary services, we won’t get Internet Explorer, accessories, RRAS, etc. We’ll get exactly what we need.

So in the datacenter Virtual Server 2005 already matters. We’re continuing to see server consolidation projects where low-utilization servers are being virtualized, saving all kinds of resources (hardware, power, physical space, etc.). Longhorn and hypervisor hold the promise of taking the advancements achieved in Virtual PC and Virtual Server, and really improving them in terms of dependability, and functionality.

PAE mode, Physical memory beyond 4GB

One of our developers was asking me how our Virtual Server 2005 machines were capable of addressing more than 4GB of memory on a 32-bit platform. This is actually a pretty interesting question that I’ve been hit with more than occasionally, so I thought I’d post a quick entry explaining this, and linking some relevant resources.

Memory is a key component in what I would term, “recently overlooked hardware components”. I say that because processing costs have come down so much, and OS platforms have improved so dramatically, that even among IT professionals, people tend forget about architecture limitations.

That being said, physical address extension (PAE) mode is memory extension provided by Intel to enable support for greater than 4GB of physical memory in 32-bit Intel architectures. Essentially, PAE maps up to 36-bits of memory to a 32-bit virtual address space, allowing for up to 64GB of physical memory.

Windows 2000 Advanced Server, Windows 2003 Enterprise edition, and Windows 2003 Datacenter edition, are all capable of accessing various amounts of physical memory beyond 4GB via PAE mode (check this link for a detailed table with memory limitations ).

Probably the key take away for IT pros is that if you’re configuring a server with more than 4GB of RAM, make sure you have the right OS to take advantage of the additional RAM.

Additional Resources:
http://www.microsoft.com/whdc/system/platform/server/PAE/pae_os.mspx
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEdrv.mspx

Update: 12/7/05
I ran across another link that provides some more depth to this...
http://www.microsoft.com/technet/prodtechnol/windowsserver2003/library/TechRef/26eccf33-2454-4222-841a-c6d5aa1fc54c.mspx

Virtual Server licensing changes

I ran across something interesting today; planned changes to the Virutal Server licensing model. It looks like these changes are going to pave the way for some really neat things, including server consolidation projects for all of us with limited budgets. Check the link, and the related documents.

Also, potentially even more exciting, is that these changes are consistent with my Vista Hypervisor thesis.

I still can’t wait to hear what we’ll get with the next version of SBS - given these changes to Virutal Server! Here’s hoping Exchange and SQL Server get virtualized into separate instances!