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VM BIOS UUIDs are not unique when virtual machines are deployed from vApp templates (2002506)

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  • When using VMware vCloud Director, multiple virtual machines in vCenter Server have the same BIOS UUID.
  • This issue is seen when editing the .vmx file of a virtual machine.

    For example:

    uuid.bios = "42 16 33 b9 01 76 de 61-c2 03 aa 2d 73 64 2c e3" 


In the default system configuration, all virtual machines that are created when you deploy a vApp template or an OVF upload are assigned the same BIOS UUID.


This behavior is controlled by a system configuration value named CloneBiosUuidOnVmCopy.

  • 1 (true) means to keep the existing BIOS UUID, and is the default value.
  • 0 (false) means to generate a new BIOS UUID.

You can use the manage-config subcommand of the cell-management-tool to view or set the value of this property. To retrieve the current value of this property, use a command like this one.

$VCLOUD_HOME/bin/cell-management-tool manage-config --lookup --name backend.cloneBiosUuidOnVmCopy
Property "backend.cloneBiosUuidOnVmCopy" has value "1".

To set this property to a value of 0, use a command like this one.

$VCLOUD_HOME/bin/cell-management-tool manage-config -n backend.cloneBiosUuidOnVmCopy -v 0
Updating property: Property "backend.cloneBiosUuidOnVmCopy" has value "0"

You must re-start all vCloud Director cells in the server group after you make this change.

Note: This change does not affect previously existing virtual machines. Also, please note that
backend.cloneBiosUuidOnVmCopy should be 0 for vSAN environments as vSAN health checking has a requirement for unique bios.uuids. Duplicate bios.uuids will give false positives for vsan.check_state find_inconsistent_vms.


See Also

This Article Replaces


Update History

01/09/2012 - Added 1.5 to product versions, and additional steps. 01/06/2012 - Linked article 1714. 02/11/2014 - Added SQL commands for Oracle.

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