As an alternative to entering the computer name or IP addresses for virtual NICs during guest operating system customization, you can create a custom application and configure it so that vCenter Server can use it to generate the computer name and IP addresses.

The application can be an arbitrary executable binary or script file appropriate for the corresponding operating system in which vCenter Server is running. After you configure a name-ip-generation application in vCenter Server, each time you initiate a guest os customization for a virtual machine, the name-ip-app is executed and an XML string is generated in place and passed to its standard input. The name-ip-generation application on its behalf should generate and return the resulting XML string through its standard output.

The application must comply with the reference XML file in the VMware knowledge base article at


Verify that Perl is installed on vCenter Server.


  1. Create the script and save it on the vCenter Server system's local disk.
  2. In the vSphere Client connected to vCenter Server, select Administration > vCenter Server Settings.
  3. Select Advanced Settings.
  4. Enter the configuration parameters for the script.
    1. In the Key text box, type
    2. In the Value text box, type c:\ and click Add.
    3. In the Key text box, type
    4. In the Value text box, type the path to the script file on the vCenter Server system and click Add. For example, type c:\
    5. In the Key text box, type
    6. In the Value text box, type c:\perl\bin\perl.exe and click Add.
  5. Click OK.


You can select the option to use an application to generate computer names or IP addresses during customization.