Download details: Installing Virtual Server on Windows SBS:

Hot off the presses tonight is a white paper to install a virtual server ‘under’ SBS… but remember you can also put SBS “under” a virtual server.  Keep in mind that SBS max’s out at 4 gig of max Ram.

We already had a poster ask for a clarification

…and Les responded back….

Hi Phillip,

There are a number of things that affect performance when running virtual
machines, especially in a production environment. But in any case, 1 GB ram
for the SBS alone is really a practical minimum for a small environment of 5
users; 2 or 3 GB of ram for the SBS will give you a large performance boost.
Personally, I haven’t seen large performance gains by exceeding 3 GB for the
SBS server, even in larger environments.

Once we add VS and virtual machines, we need to consider resource
allocation. VS is nice, as we can reserve resources for both the host and
virtual machines.

I run several production SBS networks with VS and TS apps mode servers
running as virtual machines. Acceptable performance is achieved with the
following resources allocations:

a) dual processors, with 100% of one processor reserved for each of the SBS
and the TS virtual machine.
b) 4 GB ram, either 3 GB for the SBS and 1 GB for the TS, or 2 GB each
(depending on the number of TS users, and apps being run).
c) a seperate disk subsystem for the Virtual Machine.
d) a 5 minute delayed startup for the virtual machine on host system

I haven’t run into network bottlenecks yet, but as the number of TS users
increases I expect I’ll have to address this at some point.


2 Responses to Now do you want virtual on a SBS … or a SBS in a virtual?

  1. Philipp Kohn says:

    Hi Susan,

    yes full ack!

    But what about SBS Longhorn x64, will it break the memory limits?

    W2k3 Enterprise Edition can use 64GB since SP1, before 32GB. (PAE Enabled)

    And a few fundamental hints:
    1. Don´t use the /3GB Switch because the Virtual Server driver needs kernel-memory:

    2. Exclude the virtual Server files from the realtime virus scanner:

    3. Look here for more performance hints:;en-us;903748

    4. INSTALL der Virtual Machine Additions ever!

    5. Use SCSI in the guest OS instead of IDE

    6. Use the SCSI Shunt Driver.vfd (virtual floppy disks)

    Speeding operating system installation on SCSI disks:

    7. Use differencing disks wisely and sysprep your “Template guest installation”

    8. Any further question look here:

    Regards Philipp Kohn
    mod @

  2. David says:

    I am trying to run SBS 2003 R2 inside of a Virtual Server. I have my cable modem pluged into on nic on the host machine and i have a virtual netwok configure for that nic the problem i am having is I am not sure how to configure the SBS NIC to think that it is plugged straigt to the NIC. Any help?