Configuring a SAN Environment for VMM
This topic discusses how SAN transfers work in Virtual Machine Manager (VMM) and how to configure your system for VMM to work in a SAN environment. You can deploy VMM in an environment that has either a Fibre Channel or an iSCSI storage area network (SAN) and perform SAN transfers within VMM.
VMM also supports N_Port ID Virtualization (NPIV) on a Fibre Channel SAN. NPIV uses Host Bus Adapter (HBA) technology, which creates virtual HBA ports on hosts by abstracting the underlying physical port. This support enables a single physical Fibre Channel HBA port to function as multiple logical ports, each with its own identity. Each virtual machine can then attach to its own virtual HBA port and be independently zoned to a distinct and dedicated World Wide Port Name (WWPN). For more information about NPIV and HBA technology, refer to the documentation of your HBA vendor.
|This topic provides general guidance for configuring a SAN environment for use with VMM. More specific documentation might be available from your SAN vendor.|
How SAN Transfers Work with Virtual Machine Manager
You can use VMM to perform the following types of SAN transfers between a source computer and a destination computer:
Store a virtual machine from a virtual machine host to a VMM library
Deploy virtual machines from a VMM library to a host
Note A virtual machine that is stored on a SAN is not be recognized by VMM as being deployable by SAN transfer if the virtual machine was stored directly to the library when it was created, or if the virtual machine was added to the library during a library refresh. To correct this situation, deploy the virtual machine to a host by using a local area network (LAN) transfer, and then store the virtual machine in the same VMM library, library share, and logical unit number (LUN).
Migrate a virtual machine from one host to another
Important If you migrate a virtual machine that is connected to SAN storage, the virtual machine will not be able to reconnect to the SAN unless the destination host also has access to that SAN. VMM is not able to detect if a virtual machine is connected to a SAN or if the destination host is connected to the same SAN, therefore cannot provide a warning. You must ensure that the new host is configured to allow the virtual machine to reconnect to the SAN before you migrate the virtual machine.
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.
If a properly configured SAN is available, VMM automatically uses the SAN to make transfers. However, if you use the Store Virtual Machine Wizard, Deploy Virtual Machine Wizard, or Migrate Virtual Machine Wizard to perform a transfer, you can override the SAN usage and make a local area network (LAN) transfer.
Install and Configure the Source and Destination Computers
After installing VMM, add virtual manager hosts and one or more VMM libraries as described in the VMM Help. The VMM server, VMM hosts, and VMM libraries all may be either a source or a destination computer for SAN transfers of virtual machines.
Before you can use VMM to transfer virtual machines on a SAN, you must complete the following configuration steps:
You must disable the automount functionality on any computer that you will use as either a source or a destination computer for SAN transfers.To disable automount
Open a new command prompt.
At the prompt, type automount disable.
Your computer will display the message "Automatic mounting of new volumes disabled."
VMM automatically mounts the appropriate volumes for you during the migration process. You should not attempt to manually mount volumes that have previously been migrated using Disk Manager.
Install Virtual Disk Service
If you will use a Virtual Disk Service (VDS) interface for your SAN, install VDS 1.1 on all computers that you will use as either a source or a destination computer for SAN transfers. VDS 1.1 is a component of Windows Server 2003 R2 that you can install by using Add or Remove Programs. By default, VDS 1.1 is installed if you install either of the following:
Storage Manager for SANs, a component in Windows Server 2003 R2
Windows Server 2003 SP2
In Control Panel, open Add or Remove Programs.
Click Add/Remove Windows Components, and then double-click Management and Monitoring Tools.
Select the Storage Manager for SANs check box, if it is not already selected, and then click OK.
Click Next, and then follow the instructions to install VDS 1.1.
Restart the computer.
Note Repeat this procedure for all computers that will serve as either a source or a destination location for your virtual machine SAN transfers.
Install a Virtual Disk Service Hardware Provider
If you will use a Virtual Disk Service (VDS) interface for your SAN, install a Virtual Disk Service (VDS) 1.1 hardware provider on the VMM server only. You do not need to install the provider on host or library server computers.
|VDS 1.0 and VDS 1.1 hardware providers are supported.|
You can obtain a VDS hardware provider and installation instructions from your SAN vendor. For more information about installing a VDS hardware provider, refer to the vendor's documentation.
Install a iSCSI Software Initiator for an iSCSI SAN
If you are using an iSCSI SAN, you must install the Microsoft iSCSI Software Initiator Version 2.02 on each computer that will serve as a source or a destination location for your SAN transfers. You can download this software from the Microsoft Download Center (http://go.microsoft.com/fwlink/?LinkId=88000).
|Microsoft iSCSI Software Initiator Version 2.03 and Version 2.04 are not supported.|
If your iSCSI target is configured to use one-way Challenge Handshake Authentication Protocol (CHAP) to provide security, VMM automatically generates a shared CHAP secret between the destination computer and the iSCSI target when you transfer a virtual machine on a SAN.
Install a Multipath I/O driver for a Fibre Channel SAN
If you are using a Fibre Channel SAN, you must install a Multipath I/O (MPIO) driver on all computers that are connected to your SAN, even if you are using only one host bus adapters (HBA) port on a computer. You can obtain a MPIO driver and installation instructions from your SAN vendor. For more information about installing an MPIO driver, refer to your SAN vendor's documentation.
Configure the SAN
After you have configured the source and destination computers, you must configure the SAN by:
Configuring LUNs and volumes
Configuring the SAN topology
Both of these tasks are discussed in the following sections.
Configure LUNs and Volumes
Use the following requirements to configure a logical unit number (LUN) and a volume for each virtual machine you plan to transfer on a SAN.
- Configure each LUN as a basic disk.
A virtual machine on a LUN mapped to dynamic disks cannot be transferred on a SAN.
- Create a single volume on each disk.
A virtual machine on a LUN that contains multiple volumes cannot be transferred on a SAN.
- Format the volume with the NTFS file system.
When performing SAN transfers, ensure that the selected destination path is on a volume that is also formatted with NTFS.
- Place a single virtual machine and all its associated files on each volume.
Store only one virtual machine on a volume because all files are relocated during a SAN transfer.
Important Because a virtual machine on a LUN that contains multiple volumes cannot be transferred on a SAN, and because all files are relocated during a SAN transfer, there must be only one volume per LUN and only one virtual machine per volume.
Configure the SAN topology
Ensure that all source and destination computers can access the LUN on the SAN.
For a Fibre Channel SAN, you can ensure that the source and destination computers have access to the LUN by creating the appropriate zones. For example, if you have storage array A and two hosts H1 and H2, you can create Zone1, which has host H1 and array A, and Zone2, which has host H2 and array A. The creation of these zones ensures that both host H1 and host H2 can access the LUN.
For an iSCSI SAN, you can ensure that the source and destination computers are able to access the LUN by making sure both have access at least one of the portals on the iSCSI target. As long as the source and destination computers have access at least one of the portals on the iSCSI target, you can make SAN transfers between them.