In VMware View 4.5 and later if a VM is assigned to a user their MAC address is retained after recompose operations. For non-persistent pools and for VMs that haven’t yet been assigned to a user, a recompose operation will be performed as delete-then-recreate resulting in MAC address change. Changing the MAC Address of a Virtual Machine. VMware ESX Server automatically generates MAC addresses for the virtual network adapters in each virtual machine. In most cases, these MAC addresses are appropriate. However, there may be times when you need to set a virtual network adapter’s MAC address manually — for example. Invalid MAC address specified. 12:34:6:78:90:12 is not an allowed static Ethernet address. It conflicts with VMware reserved MACs. There is a workaround to set a MAC Address out of this range. Php xdebug install mac os x. Set a custom property ethernetX.checkMACAddress=false at the VM. Where X is the number of the NIC where you want to set the MAC. For example NIC 0. VMware OUI in Static MAC Addresses By default, static MAC addresses have the VMware Organizationally Unique Identifier (OUI) as the prefix. However, the range of free address provided by the VMware OUI is restricted. Assign a Static MAC Address You can assign static MAC addresses to the virtual NIC of a powered off virtual machine by using the.
VMware ESX Server automatically generates MAC addresses for the virtual network adapters in each virtual machine. In most cases, these MAC addresses are appropriate. However, there may be times when you need to set a virtual network adapter’s MAC address manually — for example:
- You have more than 256 virtual network adapters on a single physical server.
- Virtual network adapters on different physical servers share the same subnet and are assigned the same MAC address, causing a conflict.
- You want to ensure that a virtual network adapter always has the same MAC address.
In order to work around both the limit of 256 virtual network adapters per physical machine and possible MAC address conflicts between virtual machines, the MAC addresses can be assigned manually by system administrators. VMware uses a different OUI for manually generated addresses: 00:50:56. The addresses can be set by adding the following line to a virtual machine’s configuration file:
ethernet0.address = 00:50:56:XX:YY:ZZ
where XX is a valid hex number between 00 and 3F and YY and ZZ are valid hex numbers between 00 and FF. The value for XX must not be greater than 3F in order to avoid conflict with MAC addresses that are generated by the VMware Workstation and VMware GSX Server products. Thus the maximum value for a manually generated MAC address is
ethernet0.address = 00:50:56:3F:FF:FF
VMware ESX Server virtual machines do not support arbitrary MAC addresses, hence the above format must be used. So long as you choose XX:YY:ZZ so it is unique among your hard-coded addresses, conflicts between the automatically assigned MAC addresses and the manually assigned ones should never occur. © 2001-2002 VMware, Inc. All rights reserved.
Vmware Impermissible Static Ethernet Address
Summary
# | Range or Prefix | Vendor | Virtual Machine |
---|---|---|---|
1 | 00:50:56 | VMWare | VMware vSphere, VMware Workstation, VMware ESX Server |
2 | 00:50:56:80:00:00 → 00:50:56:BF:FF:FF | VMWare | VMware vSphere managed by vCenter Server |
3 | 00:0C:29 | VMWare | Standalone VMware vSphere, VMware Workstation, VMware Horizon |
4 | 00:05:69 | VMWare | VMware ESX, VMware GSX Server |
5 | 00:1C:14 | VMWare | VMWare |
OUIs registered by VMWare, Inc
There are 4 OUIs registered by VMware, Inc:
OUI | Assignment Type |
---|---|
00:50:56 | MA-L |
00:1C:14 | MA-L |
00:0C:29 | MA-L |
00:05:69 | MA-L |
Detection Rule 1
Affects products: VMware vSphere, VMware Workstation, VMware ESX Server
Signature: OUI is 00:50:56
Conditions
When the administrator assigns the MAC address manually to a virtual machine, this OUI prefix is set automatically. The last 3 octets should be set manually.
However, administrators can set any MAC address to their virtual machines.
References
Example MACs generated
- 00:50:56:11:22:33
- 00:50:56:12:23:34
- 00:50:56:33:A1:BB
Tested on
- VMware vSphere 5.5, standalone
- VMware VMware Workstation 15
Detection Rule 2
Affects products: VMware vSphere managed by vCenter Server
Signature: MAC address belongs to the range [00:50:56:80:00:00; 00:50:56:BF:FF:FF]
Conditions
According to the VMware OUI allocation scheme, a MAC address has the format of 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.
Based on this scheme, we can determine the vCenter Server Unique ID, from the servers' MAC address:
- Take the 4th octet: for 00:50:56:97:12:34, it would be 97
- Subtract 0x80: 0x97 - 0x80 = 0x17
- Rebase it from Base-16 to to Base-10. In our example, it would be 0x17 → 23
- vCenter Server Unique ID = 23
References
Example MACs generated
- 00:50:56:A5:12:34
- 00:50:56:A5:A0:12
- 00:50:56:90:A4:BA
Tested on
- vCenter Server 5.5, 6.5
Detection Rule 3
Affects products: Standalone VMware vSphere, VMware Workstation, VMware Horizon
Signature: OUI is 00:0C:29
Conditions
According to the VMware OUI allocation scheme, the hypervisor generates MAC addresses that consists of the VMware OUI 00:0C:29 and the last three octets of the virtual machine UUID in hexadecimal format. The virtual machine UUID is based on a hash calculated by using the UUID of the ESXi physical machine and the path to the configuration file (.vmx) of the virtual machine.
References
Example MACs generated
- 00:0C:29:4E:C6:49
- 00:0C:29:49:92:99
- 00:0C:29:5C:F3:BA
Tested on
- vSphere 5.5, 6.5, VMware Workstation 15
Detection Rule 4
Affects products: Outdated VMWare solutions: VMware ESX, VMware GSX Server
Signature: OUI is 00:05:69
Conditions
According to the VMware OUI allocation scheme, the hypervisor generates MAC addresses that consists of the VMware OUI 00:05:69 and the last three octets generated by the following algorithm:
- The first 16 bits are set to the same values as the last 16 bits of the console operating system’s primary IP address.
- The final eight bits of the MAC address are set to a hash value based on the name of the virtual machine’s configuration file.
For example, if a machine's IP address was 192.34.14.81 (or in hex, 0xc0220e51) and the configuration file was hashed to the value of 95, the MAC address would have the following value: 00:05:69:0e:51:95
References:
Example MACs generated
- 00:05:69:0e:51:95
Detection Rule 5
Affects products: VMware products
Signature: OUI is 00:1C:14
References:
Example MACs generated
- 00:1C:14:00:11:22