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Virtual Machine UUID in VMware Workstation Player

Learn what a VMware virtual machine UUID is, how guests read it through SMBIOS, and how moving or copying a VM affects its identity.

A UUID (Universal Unique Identifier) is a value VMware uses to identify an individual virtual machine. In VMware Workstation Player, the UUID helps distinguish one software-defined computer from another, even when the VMs have similar operating systems or virtual hardware.

The UUID belongs to the virtual machine identity, not only to the guest operating system. A VM can be moved to another drive without becoming a different VM, while a duplicate should receive a different identity.

What a VMware virtual machine UUID means

VMware Workstation Player is desktop virtualization software that runs and manages virtual machines. A virtual machine is a software-defined computer containing virtual hardware, storage, and a guest operating system.

VMware automatically assigns a UUID to each VM. The initial UUID is generated when the VM is first powered on. During ordinary use, the UUID normally remains stable. This lets inventory systems, guest software, and administrators recognize the same VM over time.

How VMware exposes the UUID through SMBIOS

SMBIOS (System Management BIOS) is a set of system-information data structures that software can read to learn about hardware and firmware. A physical computer can expose manufacturer, model, serial, and system identity information through SMBIOS. VMware presents corresponding virtual system information to the guest.

The VM UUID is exposed in the guest's SMBIOS system information record. Hardware-inventory and firmware-inspection utilities can read that record and display the system UUID.

This guest-visible SMBIOS UUID is not necessarily the same thing as every identifier VMware may use in its own inventory or configuration files. When checking the identity from inside the guest, verify that the value is labeled System UUID, SMBIOS UUID, or an equivalent system-information field.

Finding the UUID from inside the guest

1. Start the virtual machine in VMware Workstation Player and allow the guest operating system to finish booting.
2. Open an SMBIOS-capable system-information utility inside the guest.
3. Open the utility's system-information, firmware, or SMBIOS section.
4. Locate the field labeled System UUID, SMBIOS UUID, or similar wording.
5. Record the value and compare it with the UUID from another VM only after confirming that both tools are showing the same type of field.

Examples of compatible inspection utilities include SiSoftware Sandra, smbios2, and FirmwareTablesView. Their interfaces differ, so there is no single command syntax that applies to all three. The essential task is to inspect SMBIOS system information rather than a general hardware category.

What happens when you move a VM

A move means relocating the original VM to another storage location, such as a different folder or drive. The VM files are transferred, but no second VM is intended to be created.

After VMware detects that the VM's location or copy state has changed, it can ask whether the VM was moved or copied. This question normally appears when the VM is powered on for the first time after the change.

Select Moved when you relocated the original VM. This tells VMware to preserve the existing VM identity, including its established UUID. Selecting the correct response is important when software, inventory records, or management processes depend on identity continuity.

What happens when you copy or clone a VM

A copy is a separate instance made from an existing VM. If the original and duplicate will both be operated, they need separate identities. Otherwise, inventory systems or guest-side software may treat two independent computers as the same machine.

When VMware asks whether the VM was moved or copied, select Copied for a duplicate. VMware regenerates the UUID so that the new VM can be distinguished from its source. After starting the duplicate, you can inspect its guest SMBIOS system UUID and compare it with the original.

The moved-or-copied identity decision

The prompt is an identity decision, not merely a file-management question:

• Moved: “This is the original VM, and I only changed where it is stored.” VMware should preserve the VM's established UUID.
• Copied: “This is another VM instance based on the original.” VMware should generate a distinct UUID for the duplicate.

For example, if you move a complete VM from one drive to another, open it in VMware Workstation Player, and choose Moved, the VM should continue using its existing identity. If you make a separate copy for testing and choose Copied, the test VM should receive a new UUID.

UUID stability and change conditions

The UUID normally stays unchanged when you continue using the same VM and when you relocate that original VM while correctly choosing Moved. A routine guest reboot, ordinary guest updates, or a change of storage location alone is not intended to create a new VM identity.

A new UUID can be produced when VMware treats the VM as a copy. The key event described here is selecting Copied for a duplicate at the moved-or-copied prompt. This gives separately operated VM instances distinct identities.

• Same VM, normal use: UUID normally remains stable.
• Same VM moved to another location: Choose Moved to retain the UUID.
• Separate duplicate: Choose Copied so VMware assigns a new UUID.

Practical verification examples

Checking one VM's identity

1. Power on the VM.
2. Run SiSoftware Sandra, smbios2, FirmwareTablesView, or another SMBIOS-capable utility in the guest.
3. Open the SMBIOS system-information record.
4. Note the value in the system UUID field.

The expected result is the UUID VMware presents to the guest through SMBIOS.

Relocating the original VM

1. Move the complete VM to a new storage location.
2. Open the VM in VMware Workstation Player.
3. When the identity prompt appears, choose the option indicating that the VM was moved.
4. Read the guest SMBIOS UUID again if you need to verify continuity.

The expected result is that the original UUID remains in use.

Creating a duplicate for testing

1. Make a separate copy of the VM files.
2. Open and power on the duplicate.
3. At the identity prompt, choose the option indicating that the VM was copied.
4. Read the SMBIOS system UUID in both the source and duplicate.

The expected result is two different UUID values, allowing the source and test instance to be distinguished.

Troubleshooting UUID behavior

The duplicate shows a different UUID

This is expected when the copied option was selected. Use the new UUID for the duplicate's inventory, monitoring, or licensing records. A separate VM instance should not generally reuse the original VM identity.

The UUID did not change after a storage relocation

This usually means the VM was correctly identified as moved rather than copied. No action is needed when preserving the original VM identity is the goal.

An SMBIOS utility does not show the expected UUID

The utility may be showing the wrong hardware-information category, or it may not be reading SMBIOS system data. Open the SMBIOS or firmware-table section and confirm that the displayed field is the system UUID, not another serial number or inventory value.

Two independently operated VMs appear to share an identity

A duplicate may have been treated as moved instead of copied. First determine which VM is the original and which is the duplicate. Then ensure the duplicate is started as a copied VM so VMware can assign it its own UUID. Take care to preserve the intended original before changing identity-related settings.

Exam-relevant summary

• A UUID is the unique identifier assigned to an individual VMware virtual machine.
• VMware automatically generates the initial UUID when the VM is first powered on.
• The guest can read the UUID through SMBIOS system-information data.
• SMBIOS utilities must be checked for the system UUID field, not an unrelated hardware identifier.
• Choose Moved when relocating the original VM and retaining its identity.
• Choose Copied when creating a duplicate that needs a new identity.
• Copying is the key event described here that produces a new VM UUID.

For related terminology, see Virtual Machine Universal Unique Identifier UUID.