VMware Organizationally Unique Identifier (OUI) allocation assigns MAC addresses based on the default VMware OUI 00:50:56 and the vCenter Server ID. If you reconfigure the network adapter of a powered off virtual machine, for example, by changing the automatic MAC address allocation type or setting a static MAC address, vCenter Server resolves MAC address conflicts before the adapter reconfiguration takes effect.įor information about resolving MAC address conflicts, see the vSphere Troubleshooting documentation. While this virtual machine has been powered off, its MAC address has been assigned to another virtual machine that has been powered on. The change might be caused by an address conflict with another virtual machine. When a virtual machine is powered on again, it might acquire a different MAC address. The MAC address of a powered off virtual machine is not checked against the addresses of running or suspended virtual machines. VCenter Server does not allocate MAC addresses when provisioning a virtual machine. Note: If you use invalid prefix- or range-based allocation values, an error is logged in the
