hi everyone, it has become apparent that VMM 2008 R2 has switch port leaks when performing checkpointing operations through VMM (either through the PowerShell interface, through Visual Studio Lab Manager, through the self-service portal, or through the VMM Administrator Console)
This is a known issue that we will potentially address in an upcoming QFE. For now, there is a workaround that is detailed in this blog post. Alex from our team wrote the PowerShell script that resolves this issue.
How to tell if you have switch port leaks:
- You are managing Hyper-V using VMM
- Calling the following cmdlet from PowerShell take more than 3 minutes to return: get-vmhost “<host computer name FQDN>” | refresh-vmhost???
- executing the following queries locally on the Hyper-V host from an elevated command prompt return more than a couple of hundred different objects. Running the same query command from wbemtest.exe connecting to root\virtualization as “select * from Msvm_hostedaccesspoint” for example will give you an instant count.
- ??winrm enum wmi/root/virtualization/Msvm_hostedaccesspoint
- ??winrm enum wmi/root/virtualization/Msvm_resourceallocationsettingdata
- ??winrm enum wmi/root/virtualization/Msvm_networkelementsettingdata
- winrm enum wmi/root/virtualization/Msvm_bindsto
How to fix the switch port leaks:
- Run the attached powershell script locally on the Hyper-V host from an elevated powershell window. This command will return back data on the unused networking elements in Hyper-V that were potentially leaked by VMM
- DeleteUnusedHyper-VNetworkingComponents.ps1 <hostname FQDN> no
- If you are satisfied with the objects that will potentially be deleted, run the same cmdlet with the “yes” switch.
- DeleteUnusedHyper-VNetworkingComponents.ps1 <hostname FQDN> yes
- Run refresh-vmhost again in VMM a couple of times to observe the increase in speed
- Create a scheduled task to execute this script against your Hyper-V hosts every couple of weeks.