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vSphere 4.1 upgrade pre-installation requirements and considerations (1022137)

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This article provides a quick reference of items to be considered before upgrading to vSphere 4.1, and what steps will be necessary to perform a successful migration.
Note: Many installation decisions require knowledge and understanding beyond the scope of this article. Consult the vSphere 4.1 documentation for more detailed information.



With vSphere 4.1, VMware has moved entirely to a 64-bit platform. This change brings significant performance benefits, but it also introduces some challenges that need to be considered before upgrading. vCenter Server no longer functions on a 32-bit operating system and careful planning is required to migrate your vCenter Server to a 64-bit platform.
If you have vCenter Server currently running on a 32-bit operating system (such as Windows 2000 Server or Windows 2003 Standard Edition) you cannot upgrade to the latest version of vCenter until you perform these checks:
  • Ensure that your hardware is capable of supporting a 64-bit operating system. Contact your hardware manufacturer if you are unsure if it is equipped with a 64-bit capable processor.
  • Ensure that the underlying operating system that is contained on the existing vCenter Server is 64-bit capable.
  • If the operating currently installed is 32-bit and your hardware is 64-bit capable, install a 64 bit operating system (such as Windows 2008), or migrate to another server that already has a 64-bit operating system.
  • Any database drivers (such as the SQL Native Client) need to be installed with their 64-bit counterpart. That is, the driver must be a 64-bit driver. You can install 32-bit drivers on 64-bit Windows, but these are no longer compatible for vCenter Server 4.1.

Note: VMware Update Manager 4.1 still requires a 32-bit driver for your DSN connection, as VMware Update Manager 4.1 is still a 32-bit application.

The following operating systems are supported for vCenter Server:
  • Windows XP Pro SP2 (SP2 required, 64-bit )
  • Windows Server 2003 (SP1 required, 64-bit )
  • Windows Server 2008 (64-bit)
  • Windows Server 2008 R2 (64-bit)

Note: For more information, see the vSphere Compatibility Matrix.

vCenter Server Data Migration Tool

VMware has introduced the vCenter Server Data Migration Tool to help you migrate much of your vCenter Server 4.0 configuration automatically. The Data Migration Tool is located on vCenter Server 4.1 Installation Media, under the folder datamigration. For instructions on how to use the Data Migration Tool, see the vSphere 4.1 Upgrade Guide.
There are several scenarios where this utility can assist in the migration process. However, each scenario is slightly different according to your configuration and environment. Read this article carefully and consult product documentation for further information on performing these tasks. 

You can use the vCenter Data Migration Tool to automatically migrate the following to a new server:

  • vCenter Server Software and its configuration
  • vCenter Update Manager Software and its configuration
  • VMware Orchestrator Software and its configuration
  • The default SQL Express 2005 database that comes installed with vCenter Server.

For more information on migrating your database using the Data Migration Tool, see Migrating an existing vCenter Server database to 4.1 using the Data Migration Tool (1021635).

The vCenter Data Migration Tool does not automatically:
  • Migrate databases other than SQL Express 2005 (such as Microsoft SQL 2005 Standard Edition and Oracle 11g) that are contained on the vCenter Server or that are on a remote database server.
  • Create new DSNs that point to the location of your vCenter Server and Update Manager databases (whether it is remote or local) on the new 64 bit vCenter Server. You must do this manually.

    Note: You must use a 64 bit DSN for vCenter Server and a 32 bit DSN for VMware Update Manager.

  • Update the configuration files if you are changing the IP address or the host name information of your vCenter Server. You must change the configuration files manually.

    Note: VMware recommends k
    eeping IP address and host name information the same to make migration easier.
  • Migrate software other than vCenter Server, Update Manager, or VMware Orchestrator. For example, Site Recovery Manager is not migrated.
  • Move the VMware Orchestrator database. You must do this manually.
Note: If the vCenter Server is being used as part of a VMware View environment, then the name of the vCenter should not be changed or modified.

Additional Information

See Also

Update History

07/28/2010 - Linked article 1021635. 07/16/2010 - Added information about the location of the Data Migration tool.

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