This option uses low level packet injection to simulate the function of the DsGetDcName API to allow different options to be selected, which are not available through the API. The primary reason for this option is to test CLDAP, when the NeutralizeNT feature is enabled when running in NT\Windows hybrid mode. Since NT4 has pretty much disappeared and there is not much of a requirement for this option. However, it still works with Windows 2000+ AD servers.
To use the function, you have to specify both the server and domain name.