Network Considerations

This topic describes three key things to consider when preparing your network for Virtual Machine Manager (VMM):

  • Connectivity
  • Bandwidth
  • Network traffic


You need to ensure that any firewalls in your environment do not block the necessary communication between VMM components, by ensuring that the correct ports are open. For information about the ports and protocols used in VMM, see About Assigning Ports in VMM.


Using VMM to create and manage virtual machines can involve moving multi-gigabit files across the network; for example, when you store a virtual machine from a host in the VMM library or migrate a virtual machine from one host to another.

It is a best practice to connect all computers in a VMM configuration with at least a 100-MB Ethernet connection. Using a gigabit Ethernet connection will improve performance. If you use a gigabit connection, combined with a more powerful processor on the VMM server than the recommended processor, it will further improve performance.

If your environment extends beyond a central data center to include branch offices or other remote sites where you want to create, run, and manage virtual machines, there are additional topology considerations. For more information, see Supported Configurations.

Network Traffic

VMM performs and number of periodic refreshes of the library, hosts, and virtual machines. These refreshes add to your network traffic. For very large virtual environments, this traffic can become significant.

If you use either a Fibre Channel or iSCSI SAN, you can reduce the impacts on your network by doing SAN transfers in place of transfers over the network. When you make a SAN transfer, the logical unit number (LUN) containing the virtual machine is remapped from the source computer to the destination computer instead of transferring the files over the network. Therefore, SAN transfers are much faster than standard network transfers and are independent of the size of the files being transferred. For more information about using VMM in a SAN environment, see the "Configuring a SAN Environment for VMM" topic in Deploying VMM (

If you use an iSCSI SAN, you also need to consider the network traffic created by using your iSCSI connections with VMM.

See Also


Planning for VMM Deployment
Introducing Virtual Machine Manager