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Enthusiast
Enthusiast

VMX file, difference between vc.uuid and uuid.bios

Could anyone explain the difference between the 'vc.uuid' and 'uuid.bios' entries in the guest .vmx file? Specifically, what is the 'vc.uuid' represent, and how does it get generated?

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Expert
Expert

vCenter/Virtual Center server has a unique UUID which is located in the instance.cfg file located at %ALLUSERSPROFILE%\All Users\Application Data\VMware\VMware VirtualCenter\instance.cfg

UUID.bios is the unique ID for the virtual machine, these Id's are used for the several Virtual Infrastructure tasks.

hope this helps !!

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f-10

VCP3, VCP4, HPCP, HP UX CSA

Regards, Arun Pandey VCP 3,4,5 | VCAP-DCA | NCDA | HPUX-CSA | http://highoncloud.blogspot.in/ If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".
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Enthusiast
Enthusiast

I see the 'instance uuid' in the 'instance.cfg' file, but it doesn't match the 'vc.uuid' in the guest's .vmx file. Also, this vc.uuid doesn't change even when registering the VM to a different vCenter server alltogether.

Excerpt from .vmx file:

uuid.location = "56 4d 64 d9 e6 90 39 30-49 5e 80 80 55 e2 8e 9f"

uuid.bios = "56 4d 64 d9 e6 90 39 30-49 5e 80 80 55 e2 8e 9f"

vc.uuid = "52 c8 86 91 d0 2b 2e 54-06 e8 7a 0e 0a 6a ff 0b"

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Expert
Expert

From what I have seen in the past vc.uuid is generated when VM is added to VC and my apologies for the previous comment the VC UUID in the instance.cfg should not match with vc.uuid in the VM. The vc.uuid is generated every time a virtual machine is added to vCenter.

If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".

f-10.

VCP3, VCP4, HPCP, HP UX CSA

Regards, Arun Pandey VCP 3,4,5 | VCAP-DCA | NCDA | HPUX-CSA | http://highoncloud.blogspot.in/ If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".
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Enthusiast
Enthusiast

True, it does look like it's generated with the guest is added to vCenter, however this uuid doesn't change, even when the guest is un-registered from it's original vCenter, and re-registered on a completely different one.

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Contributor
Contributor

VMware uses two UUIDs to identify a VM. One is BIOS UUID given by your ESXi Host and Instance UUID(vc.uuid) given by your Vcenter.

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