VMM 2008 supports the following virtualization platforms:

• Windows Server 2003 with Virtual Server 2005 SP1. The released version of VMM 2008 supports Windows Server 2003 32-bit; support for the 32-bit edition was not available in the pre-release version.
  
  
• Windows Server 2008 64-bit with the released version of Hyper-V.
  
  
• VMware ESX Server 3.0 or above, and VMware ESX Server 3i version 3.5, managed by VMware VirtualCenter 2.5 (VMware Infrastructure 3 environments).
  
  

The released version of VMM 2008 supports this configuration. Pre-release versions did not.

No.

VMM 2008 supports Windows Server–based and non-Windows virtual machine hosts, with the following location requirements:

• Hosts in an Active Directory domain that is trusted by the domain of the VMM server.
  
  
• Windows Server–based hosts in a non-trusted Active Directory domain.
  
  
• Windows Server–based hosts on a perimeter network. A perimeter network is an Internet Protocol (IP) network segment that contains resources, such as Web servers and virtual private network (VPN) servers, that are available to Internet users. Perimeter networks also are known as screened subnets.
  
  

  Note
  Unlike stand-alone hosts in VMM, host clusters must be in an Active Directory domain that has a two-way trust relationship with the domain that contains the VMM server.

• VMware ESX Server hosts, which VMM 2008 manages through the VMware VirtualCenter server.
  
  

No. The management of VMware ESX server hosts is agentless and is performed largely through VMware VirtualCenter Web services.

The released version of VMM 2008 supports Windows Server 2008 64-bit running Virtual Server as the virtualization platform. Pre-release versions supported only Windows Server 64-bit servers that are Hyper-V capable. On Hewlett-Packard hardware, you must enable two BIOS options: Virtualization Technology and Xbit. For more information, see your Hewlett-Packard documentation.

To find out the reason for the host’s Needs Attention state, review the detailed status on the Status tab of the host properties dialog box for items with a Warning or Error icon. For general troubleshooting, try the following steps:

1. Ensure that the host operating system, virtualization service, and Virtual Machine Manager Agent service all are running.
   
   
2. If the host is in a host cluster, ensure that the Cluster service is running.
   
   
3. Ensure that the VMM agent version is the same as the VMM server version.
   
   
4. Verify network connectivity between the VMM server and the host.
   
   
5. Ensure that the host name can be resolved by your DNS service.
   
   
6. Check the firewall policy on the host to ensure that the HTTP and HTTPS ports are open.
   
   
7. If all above are working properly, use the Refresh action in the VMM Administrator Console to refresh the host, and then, in Jobs view, monitor the job for any failure message.
   
   

Yes. If you do not want to place any additional virtual machines on a host, you can remove the host from placement. To do this, clear the This host is available for placement option on the Status tab of the host properties. This does not affect the host's status or the virtual machines that already are hosted.

This feature is not available for highly available virtual machines that are deployed on clustered hosts.

For VMware ESX Server hosts, you cannot change this property directly in Virtual Machine Manager. However, you can update the property indirectly by changing the host to maintenance mode on the VMware VirtualCenter server. VMM will update the This host is available for placement property in the VMM Administrator Console the next time it refreshes VirtualCenter data.

Concepts