Click to Rate and Give Feedback
TechNet
TechNet Library
Windows
Windows Server
Hyper-V
Getting Started
 Hyper-V Release Notes

  Switch on low bandwidth view
Hyper-V Release Notes

Applies To: Windows Server 2008

These release notes address known issues about Hyper-V™.

Known Issues

The following are the known issues for this release.

Backup

  • The data on the physical disk attached to a virtual machine, or on the Internet SCSI (iSCSI) disk attached to the guest operating system will not be included in backup when a virtual machine has either a physical disk or an iSCSI disk attached. To fix this issue, utilize backup agents inside the virtual machine and individually back up each virtual machine as if it is a physical computer.

  • Virtual machines that have dynamic volumes inside the guest operating system are supported for offline backup only when the guest operating system is configured to use dynamic disks in Disk Manager. When attempting a backup of such a virtual machine, it is saved and subsequently resumed, during the backup process. Even if the virtual machine is running, only an offline backup is taken. To avoid this issue, when using online backup, one should only use a basic disk. To fix this, either use offline backups or convert the dynamic disk to a basic disk.

  • If you restore a Volume Shadow Copy Service (VSS) based backup of a virtual machine while it is running, the virtual machine may end up in an inconsistent state. To avoid this issue, ensure that the running virtual machine is not selected in the backup application before starting the VSS restore operation, ensure that the virtual machine is turned off prior to starting the VSS restore operation or, if doing a system-wide restore, ensure that all of the virtual machines are turned off.

Security

  • If the Hyper-V authorization store is located in Active Directory®, then the removal of a user from a role does not take immediate effect. Either the server running Hyper-V (the computer that runs the Virtual Machine Management Service (VMMS)) or Active Directory needs to be rebooted to apply the changes. To avoid this issue, use an XML file as the store type. To fix this issue, reboot the Hyper-V server hosting VMMS, restart VMMS and Network Virtual Service Provider Windows Management Instrumentation (NVSPWMI) services or reboot Active Directory.

Operations

  • If you try to restart or reset a virtual machine when the physical computer is low on available memory, the virtual machine may be turned off instead of restarted. To avoid this issue, retain at least 512 MB of memory for use only on the physical computer. To fix this issue, you can try to start the virtual machine. If this does not work, you can modify the virtual machine settings to reduce the amount of memory assigned to the virtual machine.

  • While connecting through Virtual Machine Connection under a Remote Desktop session, the use of CTRL+ALT+DEL will not work. To avoid this, use CTRL+ALT+END, avoid using Virtual Machine Connection under Remote Desktop or use the CTRL+ALT+DEL options found on both the toolbar and Action menu.

  • You may encounter issues when attempting to attach virtual hard disks (VHDs) and ISOs to a virtual machine from a network share. To avoid this issue, ensure that both the Hyper-V server and the network server are members of the same domain. The network share requires read access for ISOs and read/write access for VHDs for both the user and computer account of the server running Hyper-V. If you are attempting this from a third computer (not utilizing the user interface on the server running Hyper-V), constrained delegation for Server Message Block (SMB) between the server running Hyper-V and the network file server must be enabled.

Copyright

Information in this document, including URL and other Internet Web site references, is subject to change without notice. Unless otherwise noted, the companies, organizations, products, domain names, e-mail addresses, logos, people, places, and events depicted in examples herein are fictitious. No association with any real company, organization, product, domain name, e-mail address, logo, person, place, or event is intended or should be inferred. Complying with all applicable copyright laws is the responsibility of the user. Without limiting the rights under copyright, no part of this document may be reproduced, stored in or introduced into a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise), or for any purpose, without the express written permission of Microsoft Corporation.

Microsoft may have patents, patent applications, trademarks, copyrights, or other intellectual property rights covering subject matter in this document. Except as expressly provided in any written license agreement from Microsoft, the furnishing of this document does not give you any license to these patents, trademarks, copyrights, or other intellectual property.

© 2008 Microsoft Corporation. All rights reserved.

Microsoft, Active Directory, and Hyper-V are trademarks of the Microsoft group of companies.

All other trademarks are property of their respective owners.

Community Content   What is Community Content?
Add new content RSS  Annotations
Is it supported on Hyper-V?      tonysoper ... Thomas Lee   |   Edit   |   Show History
"Is my workload supported on Hyper-V?". Now the answer is posted in KB957006 (http://support.microsoft.com/?kbid=957006) Microsoft server software and supported virtualization environments. Rock on.
This article discusses the support policy for running Microsoft server software within the following supported virtualization environments:
•Windows Server 2008 with Hyper-V
•Microsoft Hyper-V Server 2008
•Supported partners' virtualization software
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
944987 (http://support.microsoft.com/kb/944987/) Support partners for non-Microsoft hardware virtualization software
Windows Server 2008 Failover Cluster Management Update (KB 951308)      tonyso ... tonysoper   |   Edit   |   Show History

Increased functionality and virtual machine control in the Windows Server 2008 Failover Cluster Management console for the Hyper-V role (KB 951308) is now available. The KB http://support.microsoft.com/?id=951308 describes the changes in the hotfx that update the Failover Cluster Management console (the Cluadmin.msc file) and server components of the failover cluster, including:

  • Changes to the virtual machine view
    After you install this update, the actions for virtual computers are "online," "offline," "start," "stop," "shutdown," and "turnoff."
  • Changes to virtual machine actions
    After you install this update, the only action in the Failover Cluster Management console for the Hyper-V role is Move Virtual Machines. This action causes each virtual machine that is in the running state to move by using the "save state" shutdown option. If the virtual machine is not in the running state, it does not have to be shut down, and its state will not change during the move.
  • Allow for more than one virtual machine in a "Services or Applications" group
    After you install this update, the Failover Cluster Management console allows for more than one virtual machine. The High Availability Role Wizard for virtual machines identifies virtual machines that have files on the same disk and enables those virtual machines to be configured for High Availability. Therefore, the virtual machines will be in the same Services and Applications group. If the Services and Applications group moves to another node, all the virtual machines in that group are also moved.
  • Add support for mount points or volumes without a drive letter
    After you install this update, the High Availability Wizard can detect when files for a virtual machine are on a volume that is using a mount point or a GUID instead of a drive letter. Additionally, the High Availability Wizard moves the appropriate disks into the same Service or Application group as the virtual machine resource.
  • Changes to the virtual machine refresh action
    After you install this update, a refresh of a virtual machine in a group refreshes all the virtual machines in that group.
    Behavior changes if any node of the failover cluster has a disconnected virtual machine
  • Fixes the conditions that gave you the error: "An error was encountered while loading the list of available virtual machine. Value cannot be null. Parameter name: managementObject."
  • Behavior change when you add a pass-through disk to a virtual machine
    After you install this update, the Failover Cluster Management console correctly shows that the configuration change is not successful.
  • Behavior change when the parent differencing disk is not on shared storage
    Differencing disks have parent and child relationships. When a differencing disk is configured, a parent disk is specified, and that parent VHD is required to be available for the child differencing disk to function. The parent and child VHDs must be on disks that are in the same Services or Applications group as the virtual machine resource.
    Before you install this update, if the parent disk is not located correctly, the virtual machine may not start because not all the VHDs are located on the same failover cluster node. This update detects the location of the parent VHD and provides a warning if the parent VHD is not on a disk that is configured for shared storage.
  • Volume path copy
    This update lets the path of a storage volume to be copied from the properties of the disk resource in the Failover Cluster Manager console. When you configure a virtual machine, the paths of the volumes must be specified for the disks that will be used. After you apply this update, the path can be copied from the properties of the disk in the Failover Cluster Manager console. This is useful when the path is very long, such as when a volume uses a GUID instead of a drive letter.

See Also:

824684 (http://support.microsoft.com/kb/824684/LN/) Description of the standard terminology that is used to describe Microsoft software updates
950050 (http://support.microsoft.com/kb/950050/) Description of the update for the release version of the Hyper-V technology for Windows Server 2008

Virtualization Feed      tonysoper   |   Edit   |   Show History
There is a new blog and Twitter aggregator (independent bloggers and 14 Microsoft bloggers on either TechNet or MSDN) for virtualization: VirtualizationFeed at http://www.virtualizationfeed.com/.
Enabling Hyper-V Manager for Remote Administration      Jeremy Jameson   |   Edit   |   Show History

I want to point out one of the stumbling blocks that I encountered after installing the 32-bit version of KB950050 in order to use Hyper-V Manager to remotely administer a Hyper-V server (running Server Core).

According to the corresponding KB article:

Update for Windows Server 2008 (KB950050)
This 32-bit update package includes the release version of the following:

  • The Hyper-V Manager console
  • The Virtual Machine Connection tool for x86-based editions of Windows Server 2008

Based on my experience installing the Hyper-V Remote Management Update for Windows Vista (KB952627) and the note above from the KB article, after installing KB950050 on Windows Server 2008, I expected to be able to start MMC and add the Hyper-V Manager snap-in. However, it doesn't quite work that way.

To enable Hyper-V Manager after installing KB950050 for remote administration, you need to enable the corresponding feature:

  1. Open Server Manager. (If Server Manager is not running, click Start, point to Administrative Tools, click Server Manager, and then, if prompted for permission to continue, click Continue.)
  2. In Server Manager, under Features Summary, click Add Features.
  3. In the Add Features Wizard, on the Select Features page, expand Remote Server Administration Tools, and then expand Remote Administration Tools
  4. Click Hyper-V Tools, and then proceed through the rest of the wizard.
How to tell which physical disk is used for pass-through      tonysoper ... Stanley Roark   |   Edit   |   Show History
Taylor Brown's blog post shows you the WMI that will tell you what physical disk a virtual machine is using when configured for pass-thru on the host: http://blogs.msdn.com/taylorb/archive/2008/08/21/hyper-v-wmi-what-vhd-s-physical-disks
How to find event log entires      tonysoper   |   Edit   |   Show History

Hyper-V events are logged under "Application and Services Logs\Microsoft\Windows\Hyper-V-<component-name>"

- component-name could be:

  • Config
  • Integration
  • VMMS
  • Worker

Under the component node, you can find several types of event logs.

Hyper-V Increases Logical Processor Support to 24.      tonysoper   |   Edit   |   Show History

Install Windows Server 2008 Update for Windows Server 2008 x64 Edition (KB956710) enhance Hyper-V role's support for processors and virtual machines to now support up to 24 logical processors and 192 virtual machines: http://www.microsoft.com/downloads/details.aspx?FamilyID=fe36823a-7e5a-4262-9bf5-d6b3ae3ad375.

Read more at http://support.microsoft.com/kb/956710.
Note:
To start a Windows Server 2008 x86-based virtual machine on a computer that uses a 6-core processor, you also have to install hotfix 950182.
For more information, view the article in the Microsoft Knowledge Base: http://support.microsoft.com/kb/950182/

Processing
© 2009 Microsoft Corporation. All rights reserved. Terms of Use | Trademarks | Privacy Statement
Page view tracker