When a virtual machine is powered on, VMware Workstation automatically assigns each of its virtual Ethernet adapters a media access control (MAC) address. A MAC address is the unique address assigned to each physical network device. The software guarantees that virtual machines are assigned unique MAC addresses within a given host system. However, the software does not guarantee that a given virtual machine gets assigned the same MAC address every time it is powered on. In addition, VMware Workstation cannot guarantee to automatically assign unique MAC addresses for virtual machines running on multiple host systems.
If you want to guarantee that the same MAC address is assigned to a given virtual machine every time, or if you want to guarantee a unique MAC address for each virtual machine within a networked environment, you can assign the address manually instead of allowing VMware Workstation to assign it automatically.
To manually assign the same, unique MAC address to any virtual machine, use a text editor to add the following line to its configuration file (.cfg):
ethernet0.address = 00:50:56:<XX:YY:ZZ>
where XX is a valid hex number between 00h and 3Fh and YY and ZZ are valid hex numbers between 00h and FFh. Because VMware Workstation virtual machines do not support arbitrary MAC addresses, you must use this format. As long as you assign unique hard-coded MAC addresses using this format, conflicts between the automatically assigned MAC addresses and the manually assigned ones should never occur.
© 2002 VMware, Inc. All rights reserved.