Taylor Brown's Blog : Hyper-V

Attaching Passthough Disks Via WMI (SCSI or IDE)

taylorb — Fri, 16 Oct 2009 20:06:02 GMT

So you want to use passthough disks with Hyper-V cool – but how do you script attaching them? Well here’s your answer… But first you need to decide if you are going to attach them to the virtual IDE controller or the virtual SCSI controller. The IDE controller is ideal if you plan to boot from the passthough disk or if your guest doesn’t support the virtual SCSI adapter (Linux), the SCSI controller is ideal if you want to add/remove storage from the virtual machine while it’s running (feature of Hyper-V R2) or if you have more than 4 disks you want to add. Attaching to SCSI or IDE is pretty similar – there are really only 1 difference I bolded it on both scripts below you just have to select the correct controller. Other than that you can either use the physical disk number for disk manager (not too bad) or if you provide a LUN ID when you create the storage (in the case of a SAN) you can use that which can be a bit more deterministic. Either way enjoy!

Attaching Passthrough Disk To IDE Controller

$HyperVGuest = "Passthough Demo"

$VMManagementService = Get-WmiObject -class "Msvm_VirtualSystemManagementService" -namespace "root\virtualization"
$Vm = Get-WmiObject -Namespace "root\virtualization" -Query "Select * From Msvm_ComputerSystem Where ElementName='$HyperVGuest'"

$VMSettingData = Get-WmiObject -Namespace "root\virtualization" -Query "Associators of {$Vm} Where ResultClass=Msvm_VirtualSystemSettingData AssocClass=Msvm_SettingsDefineState"

$VmIdeController = (Get-WmiObject -Namespace "root\virtualization" -Query "Associators of {$VMSettingData} Where ResultClass=Msvm_ResourceAllocationSettingData AssocClass=Msvm_VirtualSystemSettingDataComponent" |`
where-object {$_.ResourceSubType -eq "Microsoft Emulated IDE Controller" -and $_.Address -eq 0})

$DiskAllocationSetting = Get-WmiObject -Namespace "root\virtualization" -Query "SELECT * FROM Msvm_AllocationCapabilities WHERE ResourceSubType = 'Microsoft Physical Disk Drive'"
$DefaultHardDisk = (Get-WmiObject -Namespace "root\virtualization" -Query "Associators of {$DiskAllocationSetting} Where ResultClass=Msvm_ResourceAllocationSettingData AssocClass=Msvm_SettingsDefineCapabilities" | `
where-object {$_.InstanceID -like "*Default"})

$Disk = Get-WmiObject -Namespace "root\virtualization" -Query "select * from Msvm_DiskDrive Where DriveNumber=2"
#$Disk = Get-WmiObject -Namespace "root\virtualization" -Query "select * from Msvm_DiskDrive Where ElementName Like '%Lun 200%'"

$DefaultHardDisk.Parent = $VmIdeController.__Path
$DefaultHardDisk.Address = 0
$DefaultHardDisk.HostResource = $Disk.__PATH

$VMManagementService.AddVirtualSystemResources($VM, $DefaultHardDisk.PSBase.GetText(1)) | ProcessWMIJob $VMManagementService "AddVirtualSystemResources"

Attaching Passthrough Disk To SCSI Controller

$HyperVGuest = "Passthough Demo"

$VMSettingData = Get-WmiObject -Namespace "root\virtualization" -Query "Associators of {$Vm} Where ResultClass=Msvm_VirtualSystemSettingData AssocClass=Msvm_SettingsDefineState"

$VmScsiController = (Get-WmiObject -Namespace "root\virtualization" -Query "Associators of {$VMSettingData} Where ResultClass=Msvm_ResourceAllocationSettingData AssocClass=Msvm_VirtualSystemSettingDataComponent" | `
where-object {$_.ElementName -eq "SCSI Controller"})

$DiskAllocationSetting = Get-WmiObject -Namespace "root\virtualization" -Query "SELECT * FROM Msvm_AllocationCapabilities WHERE ResourceSubType = 'Microsoft Physical Disk Drive'"

$DefaultHardDisk = (Get-WmiObject -Namespace "root\virtualization" -Query "Associators of {$DiskAllocationSetting} Where ResultClass=Msvm_ResourceAllocationSettingData AssocClass=Msvm_SettingsDefineCapabilities" | `
where-object {$_.InstanceID -like "*Default"})

$Disk = Get-WmiObject -Namespace "root\virtualization" -Query "select * from Msvm_DiskDrive Where DriveNumber=2"

#$Disk = Get-WmiObject -Namespace "root\virtualization" -Query "select * from Msvm_DiskDrive Where ElementName Like '%Lun 200%'"

$DefaultHardDisk.Parent = $VmScsiController.__Path

$DefaultHardDisk.Address = 0
$DefaultHardDisk.HostResource = $Disk.__PATH

$VMManagementService.AddVirtualSystemResources($VM, $DefaultHardDisk.PSBase.GetText(1)) | ProcessWMIJob $VMManagementService "AddVirtualSystemResources"

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Recommend Hotfixes For System Center Virtual Machine Manager (SCVMM)

taylorb — Tue, 14 Apr 2009 00:00:48 GMT

If your running System Center Virtual Machine Manager (SCVMM) you should take a look at KB 962941. The KB describes and links to all of the recommended Windows hotfixes, SCVMM hotfixes and Hyper-V server hotfixes that are important for SCVMM functionality.

KB Article Link: http://support.microsoft.com/kb/962941

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Hyper-V: Background Merging of AVHD’s… When’s it done?

taylorb — Wed, 11 Mar 2009 04:10:25 GMT

I think it might be best to start at ground zero with this topic and explain what a snapshot really is and how it work’s (if you already know skip a head…). Hyper-V introduced a new feature called a snapshot – snapshots allow you to capture and save the point in time state of a running or saved virtual machine and then go back to that state at a latter point in time. For example you can have a Windows XP RTM virtual machine running take a snapshot, install SP1, take a snapshot and install SP2 and then latter revert back to the SP1 snapshot and either discard the SP2 installation or keep it around so you can apply that state latter. Snapshot’s are pretty handing in this regard – you can create pretty extensive tree’s of snapshots and you can rapidly apply specific states to virtual machines. Under the covers snapshots primarily use a technology that was implemented back in the pre-Microsoft days of Virtual PC called differencing VHD’s. What a differencing VHD effectively does is point back to a parent VHD for it’s data but any updates made to the VHD reside in the new differencing VHD and subsequent requests for that same data will be overridden by the child differencing VHD. These parent child relationships can get many levels deep and a parent can have many children – however if a parent is ever modified it’s children's state is now invalid since the child was unaware of the changes. So back to snapshots – when a snapshot is taken we create a new differencing disk to point the virtual machine to and we call it an AVHD or automatic VHD since it was created automatically by requesting the snapshot – at the same time we will save off the virtual machines running state if it’s running including it’s memory state and it’s device state (network adapter IP etc…). When you revert back to a previous snapshot you reload the memory and device state and the VM is pointed at a new AVHD from the parent of that time. And that’s snapshots in a nut shell…

OK now back to topic at hand – when you delete a snapshot the next time the virtual machine is off or saved we will merge the AVHD created by the snapshot back into it’s respective parent… We do this automatically and in the background – so lets say you wanted to know when it’s was done programmatically… It’s not too hard just run the following query to see if any merges are going on presently - PS C:\> Get-WmiObject -Namespace "root\virtualization" -Query "select * from Msvm_ConcreteJob" | Where {$_.ElementName - eq 'Merge in Progress'}. Below you can see the full output of that query when a merge is occurring. Hope this helps!

PS C:\> Get-WmiObject -Namespace "root\virtualization" -Query "select * from Msvm_ConcreteJob" | Where {$_.ElementName -eq 'Merge in Progress'}

__GENUS                 : 2
__CLASS                 : Msvm_ConcreteJob
__SUPERCLASS            : CIM_ConcreteJob
__DYNASTY               : CIM_ManagedElement
__RELPATH               : Msvm_ConcreteJob.InstanceID="E3675DEB-A13C-440D-AEAD-B6CEB5ADF1D7"
__PROPERTY_COUNT        : 36
__DERIVATION            : {CIM_ConcreteJob, CIM_Job, CIM_LogicalElement, CIM_ManagedSystemElement...}
__SERVER                : TAYLORB
__NAMESPACE             : root\virtualization
__PATH                  : \\TAYLORB\root\virtualization:Msvm_ConcreteJob.InstanceID="E3675DEB-A13C-440D-AEAD-B6CEB5ADF1D7"
Cancellable             : True
Caption                 : Merge in Progress
DeleteOnCompletion      : False
Description             : Merge in Progress
ElapsedTime             : 00000000000000.000000:000
ElementName             : Merge in Progress
ErrorCode               : 0
ErrorDescription        :
ErrorSummaryDescription :
HealthState             : 0
InstallDate             : 16010101000000.000000-000
InstanceID              : E3675DEB-A13C-440D-AEAD-B6CEB5ADF1D7
JobRunTimes             : 1
JobState                : 4
JobStatus               :
LocalOrUtcTime          : 2
Name                    : Merge in Progress
Notify                  :
OperationalStatus       : {0, 0, 0}
OtherRecoveryAction     :
Owner                   :
PercentComplete         : 13                          <----Percent Complete
Priority                : 0
RecoveryAction          : 0
RunDay                  : 0
RunDayOfWeek            : 0
RunMonth                : 0
RunStartInterval        : 00000000000000.000000:000
ScheduledStartTime      : 16010101000000.000000-000
StartTime               : 16010101000000.000000-000
Status                  :
StatusDescriptions      : {, , }
TimeBeforeRemoval       : 00000000000500.000000:000
TimeOfLastStateChange   : 20090309234922.000000-000
TimeSubmitted           : 16010101000000.000000-000
UntilTime               : 16010101000000.000000-000

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Performance Smack Down - Hyper-V vs. VMware vs. Citrix

taylorb — Tue, 10 Mar 2009 01:35:33 GMT

Virtualization Review posted the results of a performance shootout between Microsoft Hyper-V, VMware ESX, and Citrix XenServer… The launched three tests against the various platforms. First was a small number of heavy workload systems, one database server running a midsize database and six VMs with heavy workload of CPU and memory. Second - was a large number of heavy workload systems, with one database server running a midsize database and twelve VMs with heavy workload of CPU, memory and disk IO. Third – was a large number of light workload systems, with one database server running a midsize database and twelve VMs running a light CPU, memory and disk IO.

Take a look at the full article – it has a bunch of raw performance data and is definitely worth at least a quick read. Full Article: http://virtualizationreview.com/features/article.aspx?editorialsid=2641

Quotes:
”Hyper-V was the first product compared, and it performed quite differently from expectations. Hyper-V has been a focus of Microsoft dev efforts, and it shows. Overall, Hyper-V did well in this comparison and proved itself a worthy product.”

“In our tests, Hyper-V did well in all categories-it's a real, viable competitor for the competition. Table 2 shows Hyper-V's comparative performance.”

“After doing these comparisons of ESX to Hyper-V and XenServer, it's clear that at the hypervisor level, ESX is optimized for a large number of less-intensive workload VMs. For intensive workloads that may not be optimized for memory overcommit apps, Hyper-V and XenServer should definitely be considered-even if that means adding another hypervisor into the data center.”

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Hyper-V VMMS Certificate Expiration Problem and Resolution

taylorb — Wed, 04 Mar 2009 09:30:45 GMT

In the coming days/weeks some of you may see some new errors from Hyper-V. The first is an error when you try and use VMConnect or SCVMM to connect to a running virtual machine – the error is “Cannot connect to the virtual machine because the authentication certificate is expired or invalid. Would you like to try connecting again?”. The second is an error when trying to start or resume saved virtual machine – the error is “'VMName' failed to initialize. Could not initialize machine remoting system. Error: ‘Unspecified error’ (0x80004005). Could not find a usable certificate. Error: ‘Unspecified error’ (0x80004005).”

This issue is fully described in KB967902 as well as a link to the HotFix. Bryon Surace also posted this on the Windows Server Blog.

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Red Hat Support Coming To Hyper-V

taylorb — Mon, 16 Feb 2009 22:43:34 GMT

Last night Mike Neil posted to the Virtualization Team Blog regarding a new agreement between Microsoft and Red Hat to bring Red Hat guest support to Hyper-V. Take a look at Mike’s full blog post Microsoft and Red Hat Cooperative Technical Support and/or the Red Hat press release Red Hat Moves to Expand Server Virtualization Interoperability. Happy day to all..

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Hyper-V Backup/Restore QFE Released

taylorb — Sat, 17 Jan 2009 00:02:31 GMT

If you are backing up your Hyper-V virtual machines using our VSS writer (backing up the physical server) you should be aware of a new Hotfix (KB959962) we released today that addresses three issues.

Issue 1
If you back up a Hyper-V virtual machine that has multiple volumes, the backup may fail. If you check the VMMS event log after the backup failure occurs, the following event is logged:

Log Name: Microsoft-Windows-Hyper-V-VMMS-Admin
Source: Microsoft-Windows-Hyper-V-VMMS
Event ID: 10104
Level: Error
Description:
Failed to revert to VSS snapshot on one or more virtual hard disks of the virtual machine '%1'. (Virtual machine ID %2)

Issue 2
The Microsoft Hyper-V VSS Writer may enter an unstable state if a backup of the Hyper-V virtual machine fails. If you run the vssadmin list writers command, the Microsoft Hyper-V VSS Writer is not listed. To return the Microsoft Hyper-V VSS Writer to a stable state, the Hyper-V Virtual Machine Management service must be restarted.

Issue 3
You cannot restore a Hyper-V virtual machine if the virtual machine was configured to use a legacy network adapter.

You can review the KB article and download the fix at http://support.microsoft.com/default.aspx?scid=kb;EN-US;959962.

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Performance Issues With Some Graphic Cards and Hyper-V

taylorb — Fri, 09 Jan 2009 11:17:00 GMT

If you are using Hyper-V on a workstation machine with a high-end or consumer graphics card you may have noticed some performance problems such as short hangs or glitches especially when running graphically intense workloads. The reason for this comes down to part of how high end graphic cards accomplish there performance conflicting with part of how Hyper-V accomplishes our performance – it’s comes down to high TLB (translation lookaside buffer) flushes

There is a KB published regarding this issue at http://support.microsoft.com/kb/961661 if you want to read more about it.

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

VHD Servicing Tool 2.0

taylorb — Tue, 06 Jan 2009 20:00:00 GMT

About a month ago I posted about the VHD Servicing tool (Offline Virtual Machine Servicing Tool). Version 2.0 of that tool was made available on December 5th – among other things this version adds support for Hyper-V (a definite plus).

Offline Virtual Machine Servicing Tool 2.0

Brief Description

This Solution Accelerator provides automated tools and guidance that IT professionals can use to update offline virtual machines efficiently and without exposing them to security risks.

Overview

The Offline Virtual Machine Servicing Tool 2.0 helps organizations maintain virtual machines that are stored offline in a Microsoft® System Center Virtual Machine Manager library. While stored, virtual machines do not receive operating system updates. The tool provides a way to keep offline virtual machines up-to-date so that bringing a virtual machine online does not introduce vulnerabilities into the organization’s IT infrastructure.
The Offline Virtual Machine Servicing Tool combines the Windows Workflow programming model with the Windows PowerShell™ interface to bring groups of virtual machines online just long enough for them to receive updates from either System Center Configuration Manager 2007 or Windows Server Update Services. As soon as the virtual machines are up-to-date, the tool returns them to the offline state in the Virtual Machine Manager library.
This Solution Accelerator includes the following components:

Brief Overview. Available online only on Microsoft TechNet. Summary for business and technical managers that briefly explains how this Solution Accelerator can fit into an organization’s IT infrastructure management strategy.
OfflineVMServicing_x64 and OfflineVMServicing_x86. Setup files for the tool, for 64 bit and 32 bit versions on Microsoft® System Center Virtual Machine Manager (VMM) 2007 or 2008.
Offline Virtual Machine Servicing Tool Getting Started Guide. Provides information about how the tool works, explains prerequisites for the tool, and describes how to install and configure the tool.
Offline_VM_Servicing_Tool_2.0_Release_Notes.rtf. Notes provide information about this release, describe known issues in the tool, and include feedback instructions.
Offline_Virtual_Machine_Servicing_Tool_Help. Help file for the tool. Provides instructions for using the tool.

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

VBScript Versions of The KVP Scripts

taylorb — Mon, 05 Jan 2009 21:00:00 GMT

Ben Armstrong (aka Virtual PC Guy) posted some great VBScript and PowerShell KVP scripts. These are a great edition to some of my earlier scripts (Adding Host KVP's, Adding Guest KVP's, Modifying KVP’s). Check them out if your looking for more samples.

Sending data from parent to virtual machine via KVP

Enumerating parent KVP data

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

New Hyper-V Case Study (MLS Property Information Network)

taylorb — Tue, 25 Nov 2008 02:00:00 GMT

A new Hyper-V case study was published late last week. In this study they also employed the Sanbolic Melio FS clustered file system – which if you haven’t looked it is absolutely worth looking at (it’s really cool). Using this file system you can place many VM’s on a single LUN which is shared across many nodes of a Hyper-V cluster – thus eliminating the one LUN per VM minimum recommended (effetely required to provide full failover functionality) by Hyper-V.

Some great quotes:

Virtualization frees the business to grow. We have been able to achieve a dynamic IT infrastructure and can almost double computing capacity on demand across the enterprise, which is huge.
    -Matt Lavallee, Director of Technology, MLS Property Information Network

The VMware solution would have required a $160,000 licensing fee, which was 30 percent of our budget for the entire solution.
    -Matt Lavallee, Director of Technology, MLS Property Information Network

With Hyper-V you can deliver consistent availability. We can now give our customers a pretty solid guarantee of 100 percent uptime without breaking the bank.
    -Matt Lavallee, Director of Technology, MLS Property Information Network

Check out the full case study at: http://www.microsoft.com/casestudies/casestudy.aspx?casestudyid=4000003046

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Running SQL Server 2008 in a Hyper-V Environment

taylorb — Mon, 24 Nov 2008 09:11:00 GMT

The SQL Performance Team has published an excellent document on running SQL Server 2008 in a Hyper-V environment. The document is 37 pages long and has detailed performance information as well as recommendations. The full document can be downloaded at:

http://download.microsoft.com/download/d/9/4/d948f981-926e-40fa-a026-5bfcf076d9b9/SQL2008inHyperV2008.docx

The key section (as far as I am concerned) is the conclusion:

Conclusion

From a performance perspective, Hyper-V is a viable option for SQL Server consolidation scenarios. The overall performance of SQL Server running in a Hyper-V virtualized environment is reasonable compared with the equivalent native Windows Server 2008 environment.

With proper I/O capacity and configuration, the I/O overhead is minimal. For best performance, you should have enough physical processors to support number of virtual processors configured on the server to avoid overcommit CPU resources. The CPU overhead increases significantly when the CPU resources are overcommitted. It is important to test each application thoroughly before you deploy it to a Hyper-V environment in production.

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Offline Virtual Machine Servicing Tool

taylorb — Thu, 13 Nov 2008 10:51:00 GMT

Many of you may have already seen this but if you haven't it's pretty cool...

From the October Issue of TechNet Magazine...
Utility Spotlight Offline Virtual Machine Servicing Tool

Download Details

This Solution Accelerator includes the following tool and documentation:

Offline Virtual Machine Servicing Tool
Offline Virtual Machine Servicing Tool Getting Started Guide
Offline Virtual Machine Servicing Tool Help file

The Offline Virtual Machine Servicing Tool is available for download from the Microsoft Download Center.

Additional Information

For more information about VMM, see the System Center Virtual Machine Manager site on Microsoft TechNet.

For more information about Configuration Manager, see the System Center Configuration Manager site on TechNet .

For more information about WSUS, see the Microsoft Windows Server Update Services site on TechNet.

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Windows Server 2008 R2 Beta Reviewers Guide Posted

taylorb — Fri, 07 Nov 2008 08:08:36 GMT

The Windows Server 2008 R2 (Beta) Reviewers Guide has been posted, 74 pages of riveting marketing stuff about Windows Server 2008 R2 – they actually do a pretty good job talking about a new clustering feature specifically for Hyper-V named Cluster Shared Volumes (CSV). CSV allows multiple cluster nodes to utilize the same LUN at the same time allowing multiple virtual machines to co-exist on the same physical LUN while the virtual machines are running on different nodes. CSV is only going to be supported for Hyper-V environments and will be highly recommended to enable Live Migration…

There are many more features in Server 2008 R2 specific to virtualization – I will continue to provide details around those features as well as links to resources.

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Hyper-V PowerGUI PowerPack – Now That’s Power….

taylorb — Thu, 23 Oct 2008 08:52:07 GMT

I loved PowerGUI ever since I found it a month ago or so… Well Kirk and the PowerGUI guys have done it again… They now have a pretty comprehensive PowerShell wrapper for Hyper-V… Pretty Cool!

http://poshoholic.com/2008/10/22/powergui-now-with-100-more-hyper-v/
As of today, PowerGUI users can download a free Hyper-V PowerPack for PowerGUI! This PowerPack has been a huge undertaking, to put it mildly, and I’m absolutely thrilled with the end result (and so happy that I’ve finally finished the first version…whew)! Here’s a list of some of the key features that this PowerPack provides:

Bulk management of multiple VMs, Virtual Networks, Virtual Hard Drives, Snapshots, etc. within one Hyper-V servers and across multiple Hyper-V servers.
Support for remote management of Hyper-V servers using alternate credentials.
Integrated management of standard Windows features like Processes, Services, Event Logs, etc.
Automatic credential caching (in memory, not to disk) allowing you to enter a password for a Hyper-V server you are managing only once per PowerGUI session.
Discovery of Hyper-V servers through Active Directory.
Over 30 rich user-defined functions that wrap the Hyper-V WMI interfaces and provide a cmdlet-like experience when scripting with Hyper-V while outputting rich, custom objects complete with properties and methods to script to your heart’s content. Many of these functions support CSV input through Import-Csv, so there are a lot of opportunities for provisioning already available.
101 links and actions allowing you to manage just about everything you would want to manage in Hyper-V, including configuration of security via AzMan Scopes, Snapshot refresh, and many, many more.

Download: http://www.powergui.org/entry.jspa?externalID=2142&categoryID=21

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb