John Howard - Senior Program Manager in the Hyper-V team at Microsoft

Senior Program Manager, Hyper-V team, Windows Core Operating System Division.

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Exchange 2003 SP2 under Virtual Server 2005 R2

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More blogging this for my own reference rather than it being really new information. KB Article 320220 documents the support policy for Exchange Server 2003 running under Virtual Server 2005 R2 - what you can do, and more importantly what you can't do (such as run an Exchange cluster for example).
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  • Hi John!
    As an FYI there is a fairly egregious error in this KB, speficially:
    "The network adaptor in the guest operating system will have a maximum bandwidth of 100 megabits. When you size the disk capacity of the virtual machine, the time that is required to perform a full online backup of the Exchange Server data over the network should be considered. Consider adding a dedicated virtual network adaptor for Exchange Server backups."

    The NIC in a virtual machine is not constrained to 100 Mb/s as the article states. On a host with Gigabit ethernet it is quite possible that you'll see speeds well in excess of 100 Mb/s. I've been trying for a while now to have someone correct this.

  • Hi Paul! Long time no hear.

    ...so if we wait a few months, it may get amended :-)

    Absolutely right. Common misunderstanding is that it's the emulated adapter is emulated so well that it really does _appear_ in hardware manager and similar tools to be a physical adapter with a speed limitation of 100MBPs in guests. The reality is that (apart from a small virtualisation overhead), it will run at the throughput of the underlying physical host adapter.

    However - the article is correct in as much as if are doing heavy-weight network throughput from a VM, it's worth sticking in another host adapter just for that VM's dedicated use. No point starving everything else.

    Cheers,
    John.

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