Monday, April 25, 2011

Ask your Hyper-V or any other software fundamentals questions here...

If you have questions about Hyper-V or other topics around software fundamentals in general you can post a comment here and in due time I'll answer it.


  1. How to reserve resources (memory, cpu, i/o) for Hyper-V host?

  2. [Tony's reply] This is a good question. Hyper-V has what it calls a "reserve" amount of memory it dedicates for the root. In later releases R2 and beyond this is around 512MB in earlier releases it was 64MB. However what it seems like you are asking is how much memory should you reserve and how do you make sure VM's dont use it. In general you should plan to give each VM about (MM - 64*NN) / NN amount of memory where MM is the total system memory and NN is the number of VM's. If you set the VM [max] memory this way you can be sure the host will have what it needs. For disk intensive workloads you might want to reserve a little more.

  3. Hi There.

    I am currently implementing monitoring of Hyper-V servers via Kaseya.
    Using the 'Hyper-V machine health summary' 'health okay' counter has me completely stuffed.
    I am having trouble working out what is an okay condition?

    Most of my servers are reporting '4' but some of them are reporting '3'

    I cannot work out if this is the number of healthy VMs or if this is some other measurement that is undefined (no amount a googling has provided me with a satisfactory answer)

    Any assistance would be greatly appreciated.


    David Tocker

  4. Hi!
    How can you monitor performance on HyperV 2008 Server R2 SP1? I read your article regarding what counters needed to be monitored for Hyper-V but PerfMon is unable to connect to the RPC Server on the host machine. I'm assuming that the HyperV 2008 Server doesn't have an RPC server.What tool do use for monitoring performance on HyperV 2008 Server R2 SP1?

    Thanks in advance!

  5. On thing to keep in mind is perfmon is authenticated and so you need a shared user between systems.

    More specifically... see how to access perf counters remotely in the FAQ.

    Please let me know if this resolves your issue.

  6. Hi,
    You wrote in your earlier blogpost, , that "We could have provided some VM specific data inside the guest and might in the future. However our current thinking is not to do this."

    Has this changed recently ? Is there a way to access hyper-v specific counters locally without having to use remote management APIs ?
    Any pointers would be greatly appreciated !