Every system has a universally unique identifier (UUID) value set onto the system. The UUID is a 128-bit value typically displayed in lowercase hexadecimal digits in 5 groups separated by dashes. An example UUID would look like 5178962d-2fcf-df50-536d-000423d9985a.

While software packages may make use of pseudo random UUIDs, this article will cover only system hardware UUIDs.

Windows[edit]

You may get the UUID value from PowerShell.

> get-wmiobject Win32_ComputerSystemProduct | Select-Object -ExpandProperty UUID

Linux / FreeBSD[edit]

Use the dmidecode utility to get the UUID

# dmidecode -s system-uuid

You may need to install dmidecode since it usually isn't bundled with the base OS. On FreeBSD, it's available in ports at /usr/ports/sysutils/dmidecode.

VMWare ESXi[edit]

To get the UUID of the physical machine that your ESXi server is running on, login via SSH and run:

# esxcfg-info | grep -i uuid

You will see a bunch of UUIDs, most of which pertain to disks/volumes. What you are looking for is:

 |----System UUID..............................................5178962d-2fcf-df50-536d-000423d9985a