VMware Organizationally Unique Identifier (OUI) allocation assigns MAC addresses based on the default VMware OUI 00:50:56 and the vCenter Server ID.

VMware OUI allocation is the default MAC address assignment model for virtual machines. The allocation works with up to 64 vCenter Server instances, and each vCenter Server can assign up to 64000 unique MAC addresses. The VMware OUI allocation scheme is suitable for small scale deployments.

According to the VMware OUI allocation scheme, a MAC address has the format 00:50:56:XX:YY:ZZ where 00:50:56 represents the VMware OUI, XX is calculated as (80 + vCenter Server ID), and YY and ZZ are random two-digit hexadecimal numbers.

The addresses created through the VMware OUI allocation are in the range 00:50:56:80:YY:ZZ - 00:50:56:BF:YY:ZZ.