The library provides a central, secure, definitive store for the resources used to create virtual machines in your organization. Using the library helps promote re-use of approved images and configurations.

To configure the library, you create the library shares on the servers that you want to use and then add the servers, specifying which shares you want VMM to index during library refreshes. You can do this by using the Add Library Servers Wizard, which is available in any view of the VMM Administrator Console. To add additional library shares later, you can use the Add library shares action, available in Library view. You can add only existing shares; VMM does not create the shares.

To enhance performance and reduce network traffic during virtual machine creation, it’s important to store the files that you use to create virtual machines near the hosts you will use to stage virtual machine creation. You can use the library group property of library servers to help associate library servers with the host groups they will serve. For more information, see Planning for the VMM Library.

VMM also supports highly available library servers, created by adding a Windows Server 2008 or Windows Server 2008 R2 failover cluster. This option is discussed in detail a little later in this topic.

During library refreshes, the following types of files are added to available resources in Library view: virtual hard disks (unless attached to a stored virtual machine), virtual floppy disks, ISO images, answer files, and PowerShell scripts.

A library refresh also indexes, but does not display, all files associated with stored virtual machines, including the virtual machine configuration file, attached virtual hard disks, saved state files, imported snapshots, checkpoints, and the files associated with virtual machine templates. In the navigation pane of Library view, stored virtual machines and templates are displayed in the VMs and Templates node for the library server that stores the files that are associated with them. You can view snapshots and checkpoints for a virtual machine on the Checkpoints tab in the virtual machine properties.

For a complete listing of indexed file types, see File Types That Are Indexed During a Library Refresh.

By default, VMM refreshes all library shares once every hour. If you need an immediate refresh, you can manually refresh an individual library share or all library shares on a library server by selecting the share or server in the Library view of the VMM Administrator Console and then clicking Refresh share.

To change the library refresh interval, display Administration view of the VMM Administrator Console, click General, and then click Library Settings in the results pane. In the Actions pane, under Settings, click Modify. In the Library Settings dialog box, set the number of hours between refreshes. One hour is the minimum interval.

You can move the files by copying them to a library share on another library server. During the next library refresh, VMM will refresh the metadata in the VMM database.

When you remove a library server or library share from VMM, the files are not deleted from the file system. The only change is that the metadata is removed from the VMM database. Likewise, VMM removes all library objects—such as templates, hardware profiles, software profiles, and stored virtual machines—that are associated with files on a removed library share from the VMM database.

The virtual machine configuration file is used only to import the virtual machine into VMM. After the virtual machine has been imported, there are no actions that a VMM administrator or self-service user can take on a configuration file. For this reason, the configuration file is not displayed.

If the virtual hard disk is attached to a virtual machine, the virtual hard disk file does not show up in the library as a resource. If you view the properties of the virtual machine that the VHD is attached to, you will see the reference to the VHD.

The folder will show up in the library only if it contains a file type that is managed by the VMM library. VMM also does not add hidden folders to the library. For more information, see File Types That Are Indexed During a Library Refresh.

By creating a virtual machine template, you can generalize a virtual machine to create a reference image that can be used repeatedly. Templates are metadata only and exist in the VMM database, not in the file system.

In Library view, virtual machines and templates appear in the VMs and Templates node under any library server that stores physical files that the virtual machines or templates reference. For example, a single template might appear on multiple library servers if it used an ISO image on one library server and a VHD on another.

All guest operation system profiles and hardware profiles appear in the Profiles node—the bottom node in the navigation pane.

The following illustration shows where to find templates, profiles, and virtual machines in the navigation pane of Library view.

In VMM, you can view and run your Windows PowerShell scripts from the library by using the View PowerShell script and Run PowerShell script actions in Library view. These features are available only if you store your PowerShell scripts in the library. However, you do not have to store scripts in the library to run them from the command line. Running a script from the library requires the same permissions that a user needs to run that same script from outside the VMM Administrator Console.

If the scripts in your library are not signed and your computer has a policy to run only signed scripts, you will not be able to run scripts from the library. For details about script signing, in PowerShell Help, see About_signing (http://go.microsoft.com/fwlink/?LinkId=119744). If you are unable to sign scripts, you can change the policy on your computer by using the Set-ExecutionPolicy cmdlet in Windows PowerShell.

Yes. VMM supports highly available library servers that are configured as a failover cluster in Windows Server 2008 or Windows Server 2008 R2. VMM does not support clusters created in Windows Server 2003. Nor does VMM support using a failover cluster that contains the VMM server as a highly available library server.

In the Add Library Server Wizard, enter the highly available file server name as the library server name. The highly available file server name, also known as the Client Access Point, usually is different from the cluster name. The wizard discovers all of the nodes of the cluster and then adds the highly available file server to Library view. The nodes will not be displayed in Library view but will be displayed in Administration view, under Managed Computers.

VMM does not refresh cluster node membership after a highly available library server is added. If a node is added to the cluster after you add a highly available library server to VMM, you must manually add the node to the library server by using either the Add Library Server Wizard or the Add-LibraryServer cmdlet. The new node will not be displayed in Library view until a library share is added to that node. To find out the nodes in a highly available library server, view the library server properties or use the Discover-Cluster cmdlet in Windows PowerShell.

You remove a highly available library server in the same way that you remove a stand-alone library server. However, removing the highly available file server removes only the cluster name, not the nodes. The nodes are not removed because they might be supporting a different highly available file server. To remove the nodes as library servers, in Administration view, click Managed Computers, select the nodes, and then, in the Actions pane, click Remove.

When you create a new highly available file server in Windows Server 2008 or Windows Server 2008 R2, it will take a few minutes for the new DNS name to propagate in Active Directory Domain Services. Try again in a few minutes.